BGP

This chapter provides information on configuring BGP.

Topics in this chapter include:

BGP Overview

Border Gateway Protocol (BGP) is an inter-autonomous system routing protocol. An autonomous system (AS) is a network or a group of routers logically organized and controlled by a common network administration. BGP enables routers to exchange network reachability information, including information about other ASs that traffic must traverse to reach other routers in other ASs. In order to implement BGP, the AS number must be specified in the config>router context. A 7705 SAR BGP configuration must contain at least one group (a collection of related BGP peers) and include information about at least one neighbor (peer).

AS paths are the routes to each destination. Other attributes, such as the path’s origin, the system’s route preference, aggregation, route reflection, and communities included in the AS path are called path attributes. When BGP interprets routing and topology information, loops can be detected and eliminated. Route preference for routes learned from the configured peers can be enabled among groups of routes to enforce administrative preferences and routing policy decisions.

This section contains information about the following topics:

BGP Communication

There are two types of BGP peers: internal BGP (IBGP) peers and external BGP (EBGP) peers (see BGP Configuration).

  • Within an AS, IBGP is used to communicate with peers.

  • Between ASs, EBGP is used to communicate with peers. Routes received from a router in a different AS can be advertised to both EBGP and IBGP peers.

    In an external group, the next hop depends upon the interface shared between the external peer and the specific neighbor. The multihop command must be specified if an EBGP peer is more than one hop away from the local router.

The 7705 SAR supports EBGP within the router context and VPRN context. For information on configuring EBGP within the VPRN context, see the 7705 SAR Services Guide, ‟VPRN Services”. IBGP is supported within a router context but not within a VPRN context.

Autonomous systems use BGP to share routing information — such as routes to each destination and information about the route or AS path — with other ASs. Routing tables contain lists of known routers, reachable addresses, and associated path cost metrics to each router. BGP uses the information and path attributes to compile a network topology.

Figure 1. BGP Configuration

Static and Dynamic Neighbors

The 7705 SAR supports both statically configured and dynamic (unconfigured) BGP sessions. Statically configured BGP sessions are configured using the BGP group neighbor ip-address command. Dynamic sessions are established using one or more prefix commands in the BGP group dynamic-neighbor context. The neighbor command accepts either an IPv4 or IPv6 address, which allows the session transport to be IPv4 or IPv6. By default, the router is the active side of TCP connections to statically configured remote peers, meaning that as soon as a session leaves the idle state, the router attempts to set up an outgoing TCP connection to the remote neighbor and listens on TCP port 179 for an incoming connection from the peer. If required, a statically configured BGP session can be configured for passive mode, meaning that the router only listens for an incoming connection and does not attempt to set up the outgoing connection. For dynamic sessions, the router always operates in passive mode.

The source IP address used to set up the TCP connection to the static or dynamic peer can be configured explicitly using the local-address command. If a local-address is not configured, the source IP address is determined as follows:

  • if the neighbor’s IP address belongs to a local subnet, the source IP address is the local router’s interface IP address on that subnet

  • if the neighbor’s IP address does not belong to a local subnet, the source IP address is the local router’s system IP address

Configuring the router interface as the local address can be done in the config>router>bgp>group context and the config>router>bgp>group>neighbor context.

When the router interface is configured as the local address, BGP inherits the IP address from the interface as follows:

  • BGP-4 sessions — the primary IPv4 address configured on the interface is used as the local address

  • BGPv6 sessions — the primary IPv6 address configured on the interface is used as the local address

If the corresponding IPv4 or IPv6 address is not configured on the router interface, the BGP sessions that have this interface set as the local address are kept in the down state until an interface address is configured on the router interface.

If the primary IPv4 or IPv6 address is changed on the router interface and that interface is being used as the local address for BGP, BGP will bounce the link. Bouncing the link causes all routes advertised using the previous address to be removed and readvertised using the newly configured IP address.

Message Types

Four message types are used by BGP to negotiate parameters, exchange routing information and indicate errors. They are:

  • Open message — after a transport protocol connection is established, the first message sent by each side is an Open message. If the Open message is acceptable, a Keepalive message confirming the Open message is sent back. Once the Open message is confirmed, Update, Keepalive, and Notification messages can be exchanged.

    Open messages consist of the BGP header and the following fields:

    • version — the current BGP version number is 4

    • local AS number — the autonomous system number is configured in the config>router context

    • hold time — the maximum time BGP will wait between successive messages (either Keepalive or Update) from its peer, before closing the connection. Configure the local hold time within the config>router>bgp context.

    • BGP identifier — IP address of the BGP domain or the router ID. The router ID must be a valid host address.

  • Update message — Update messages are used to transfer routing information between BGP peers. The information contained in the packet can be used to construct a graph describing the relationships of the various autonomous systems. By applying rules, routing information loops and some other anomalies can be detected and removed from the inter-AS routing.

    The Update messages consist of a BGP header and the following optional fields:

    • unfeasible routes length — the length of the field that lists the routes being withdrawn from service because they are considered unreachable

    • withdrawn routes — the associated IP address prefixes for the routes withdrawn from service

    • total path attribute length — the total length of the path field that provides the attributes for a possible route to a destination

    • path attributes — the path attributes presented in variable-length TLV format

    • network layer reachability information (NLRI) — IP address prefixes of reachability information

  • Keepalive message — Keepalive messages, consisting of only a 19-octet message header, are exchanged between peers frequently so hold timers do not expire. The Keepalive messages determine if a link is unavailable.

  • Notification message — A Notification message is sent when an error condition is detected. The peering session is terminated and the BGP connection (TCP connection) is closed immediately after sending it.

BGP Path Attributes

Path attributes are fundamental to BGP. A BGP route for a particular NLRI is distinguished from other BGP routes for the same NLRI by the set of path attributes for the route. Each path attribute describes some property of the path and is encoded as a TLV in the Path Attributes field of the Update message. The Type field of the TLV identifies the path attribute and the Value field carries data specific to the attribute type. There are four categories of path attributes:

  • well-known mandatory

    These attributes must be recognized by all BGP routers and must be present in every Update message that advertises reachable NLRI toward a specific type of neighbor (EBGP or IBGP).

  • well-known discretionary

    These attributes must be recognized by all BGP routers but are not required in every Update message.

  • optional transitive

    These attributes do not need to be recognized by all BGP routers. If a BGP router does not recognize one of these attributes, it accepts it and passes it on to other BGP peers.

  • optional non-transitive

    These attributes do not need to be recognized by all BGP routers. If a BGP router does not recognize one of these attributes, it is quietly ignored and not passed on to other BGP peers.

The 7705 SAR supports the following path attributes:

  • ORIGIN (well-known mandatory)

  • AS_PATH (well-known mandatory)

  • NEXT_HOP (well-known, mandatory only in Update messages with IPv4 prefixes in the NLRI field)

  • MED (optional non-transitive)

  • LOCAL_PREF (well-known, mandatory only in Update messages sent to IBGP peers)

  • ATOMIC_AGGREGATE (well-known discretionary)

  • AGGREGATOR (optional transitive)

  • COMMUNITIES (optional transitive)

  • ORIGINATOR_ID (optional non-transitive)

  • CLUSTER_LIST (optional non-transitive)

  • MP_REACH_NLRI (optional non-transitive)

  • MP_UNREACH_NLRI (optional non-transitive)

  • EXT_COMMUNITY (optional transitive)

  • AS4_PATH (optional transitive)

  • AS4_AGGREGATOR (optional transitive)

  • CONNECTOR (optional transitive)

  • PMSI_TUNNEL (optional transitive)

  • TUNNEL_ENCAPSULATION (optional transitive)

  • AIGP (optional non-transitive)

  • BGP-LS (optional non-transitive)

Origin Attribute

The ORIGIN attribute indicates the origin of the path information. There are three supported values:

  • IGP (0) – the prefix was originated from information learned from an interior gateway protocol

  • EGP (1) – the prefix originated from an exterior gateway protocol (BGP)

  • Incomplete (2) – the prefix originated from an unknown source

AS Path Attribute

The AS_PATH attribute contains the list of ASs through which the routing information has passed.

The AS numbers in the AS_PATH attribute are all 2-byte values or all 4-byte values (if the 4-octet ASN capability was announced by both peers).

Next-hop Attribute

The NEXT_HOP attribute indicates the IPv4 address of the BGP router that is the next hop to reach the IPv4 prefixes in the NLRI field. If the Update message is advertising routes other than IPv4 unicast routes, the next hop of these routes is encoded in the MP_REACH_NLRI attribute; see Multiprotocol BGP Extensions Attributes for more details.

MED Attribute

The Multi-Exit Discriminator (MED) attribute is an optional attribute that can be added to routes advertised to an EBGP peer to influence the flow of inbound traffic to the AS. The MED attribute carries a 32-bit metric value. A lower metric is better than a higher metric when MED attributes are compared during the BGP decision process. Unless the always-compare-med command is configured, MED attributes are compared only if the routes come from the same neighbor AS. By default, if a route is received without a MED attribute, it is evaluated by the BGP decision process as though it had a MED containing the value 0. This can be changed so that a missing MED attribute is handled in the same way as a MED with the maximum value. The 7705 SAR always removes the received MED attribute when advertising the route to an EBGP peer.

Local Preference Attribute

The LOCAL_PREF attribute is a well-known attribute that should be included in every route advertised to an IBGP peer. It is used to influence the flow of outbound traffic from the AS. The local preference is a 32-bit value, and higher values are more preferred by the BGP decision process. The LOCAL_PREF attribute is not included in routes advertised to EBGP peers. If the attribute is received from an EBGP peer, it is ignored.

Route Aggregation Path Attributes

An aggregate route is a group of routes with a common prefix that are combined into a single entry in the forwarding table (for more information, see the aggregate command in the 7705 SAR Router Configuration Guide, ‟Router Global Commands”).

An active aggregate route can be advertised to a BGP peer by exporting it into BGP. This reduces the number of routes that need to be advertised to the peer and reduces the number of routes in the peer AS. When a router advertises an aggregate route to a BGP peer, the aggregation attributes in the route are set as follows.

  • The ATOMIC_AGGREGATE attribute is included in the route if at least one contributing route has the ATOMIC_AGGREGATE attribute, or the aggregate route was formed without the as-set option in the config>router>aggregate context and at least one contributing route has a non-empty AS_PATH. The ATOMIC_AGGREGATE attribute indicates that some of the AS numbers present in the AS paths of the contributing routes are missing from the advertised AS_PATH.

  • The AGGREGATOR attribute is added to the route. This attribute encodes, by default, the global AS number and router ID (BGP identifier) of the router that formed the aggregate, but these values can be changed on a per-aggregate route basis using the aggregator command option in the config>router> aggregate context. The AS number in the AGGREGATOR attribute is either 2 bytes or 4 bytes (if the 4-octet ASN capability was announced by both peers). The router ID in the aggregate routes advertised to a particular set of peers can be set to 0.0.0.0 using the aggregator-id-zero command in the config>router> bgp context.

Communities Attribute

A BGP route can be associated with one or more communities. There are two kinds of BGP communities supported by the 7705 SAR:

  • standard communities (each 4 bytes in length, all packed into a path attribute with type code 8)

  • extended communities (each 8 bytes in length, with potentially many possible subtypes, all packed into a path attribute with type code 16)

For information about communities, see the 7705 SAR Router Configuration Guide, ‟Route Policies”.

The COMMUNITIES attribute is an optional transitive attribute of variable length. The attribute consists of a set of four octet values, each of which specifies a community. All routes with this attribute belong to the communities listed in the attribute.

The following communities are well-known standard communities that should be recognized by all BGP routers:

  • NO_EXPORT – a route that carries this community must not be advertised outside the local AS

  • NO_ADVERTISE – a route that carries this community must not be advertised to any other BGP peer

  • NO_EXPORT_SUBCONFED – a route that carries this community must not be advertised outside a member AS boundary to external BGP peers

Route Reflection Attributes

The ORIGINATOR_ID and CLUSTER_LIST attributes are optional non-transitive attributes that are used in route reflection; see Route Reflection.

Multiprotocol BGP Extensions Attributes

Multiprotocol extensions for BGP (MP-BGP) allow BGP peers to exchange routes for NLRI other than IPv4 prefixes; for example, IPv6 prefixes or Layer 3 VPN routes. A BGP router that supports MP-BGP indicates the types of routes it wants to exchange with a peer by including the corresponding AFI (Address Family Identifier) and SAFI (Subsequent Address Family Identifier) values in the MP-BGP capability fields of its Open message.

To advertise reachable routes of a particular AFI/SAFI, a BGP router includes a single MP_REACH_NLRI attribute in the Update message. The MP_REACH_NLRI attribute encodes the AFI, the SAFI, the BGP next hop, and all the reachable NLRI.

To withdraw routes of a particular AFI/SAFI, a BGP router includes a single MP_UNREACH_NLRI attribute in the Update message. The MP_UNREACH_NLRI attribute encodes the AFI, the SAFI, and all the withdrawn NLRI.

4-Octet AS Attributes

The AS4_PATH and AS4_AGGREGATOR attributes are optional transitive attributes that support the gradual migration of routers that can understand and parse 4-octet ASN numbers.

AIGP Metric Attribute

The accumulated IGP (AIGP) metric attribute is an optional non-transitive attribute that can be attached to selected routes (using route policies) in order to influence the BGP decision process to prefer BGP paths with a lower end-to-end IGP cost, even when the compared paths span more than one AS or IGP instance. AIGP is different from MED in several important ways.

  • AIGP is not intended to be transitive between completely distinct ASs (only across internal AS boundaries).

  • AIGP is always compared in paths that have the attribute, regardless of whether they come from different neighbor ASs.

  • AIGP is more important than MED in the BGP decision process.

  • AIGP is automatically incremented every time there is a BGP next-hop change, so that it can track the end-to-end IGP cost. All arithmetic operations on MED attributes must be done manually (for example, using route policies).

The 7705 SAR supports AIGP for the following address families in the GRT context:

  • IPv4

  • label-IPv4

  • IPv6

The AIGP attribute is only sent to peers that are configured with the aigp command. If the attribute is received from a peer that is not configured for aigp, or if the attribute is received in an unsupported route type, the attribute is discarded and is not propagated to other peers. However, it is still displayed in BGP show commands.

When a 7705 SAR receives a route with an AIGP attribute and readvertises the route to an AIGP-enabled peer without any change to the BGP next hop, the AIGP metric value is unchanged by the advertisement (RIB-OUT) process. However, if the route is readvertised with a new BGP next hop, the AIGP metric value is automatically incremented by the route table cost (or tunnel table cost) to reach the received BGP next hop and/or is incremented by a statically configured value (using route policies).

Multiprotocol BGP Attributes

Multiprotocol BGP Attributes (MP-BGP) allows BGP peers to exchange routes for NLRI other than IPv4 prefixes; for example, IPv6 prefixes, Layer 3 VPN routes, Layer 2 VPN routes, and flow-spec rules. A BGP router that supports MP-BGP indicates the types of routes it wants to exchange with a peer by including the corresponding AFI (Address Family Identifier) and SAFI (Subsequent Address Family Identifier) values in the MP-BGP capability of its OPEN message. The two peers forming a session do not need indicate support for the same address families; as long as there is one AFI/SAFI in common the session will establish and routes associated with all the common AFI/SAFI can be exchanged between the peers.

The list of AFI/SAFI advertised in the MP-BGP capability is controlled entirely by the family commands. The AFI/SAFI supported by the 7705 SAR and the method of configuring the AFI/SAFI support is summarized in Multi-Protocol BGP Support on 7705 SAR.

Table 1. Multi-Protocol BGP Support on 7705 SAR

Name

AFI

SAFI

Configuration Commands

IPv4 unicast

1

1

family ipv4

IPv4 labeled unicast

1

4

family label-ipv4

NG-MVPN IPv4

1

5

family mvpn-ipv4

VPN-IPv4

1

128

family vpn-ipv4

RT constrain

1

132

family route-target

IPv6 unicast

2

1

family ipv6

IPv6 labeled unicast

1

4

family label-ipv6

VPN-IPv6

2

128

family vpn-ipv6

BGP-LS

16388 (base)

16388 (VPN)

71 (base)

128 (VPN)

family bgp-ls

To advertise reachable routes of a particular AFI/SAFI a BGP router includes a single MP_REACH_NLRI attribute in the UPDATE message. The MP_REACH_NLRI attribute encodes the AFI, the SAFI, the BGP next-hop and all the reachable NLRI. To withdraw routes of a particular AFI/SAFI a BGP router includes a single MP_UNREACH_NLRI attribute in the UPDATE message. The MP_UNREACH_NLRI attribute encodes the AFI, the SAFI and all the withdrawn NLRI. While it is valid to advertise and withdraw IPv4 unicast routes using the MP_REACH_NLRI and MP_UNREACH_NLRI attributes, 7705 SAR always uses the IPv4 fields of the UPDATE message to convey reachable and unreachable IPv4 unicast routes.

BGPv6

The 7705 SAR supports BGPv6 in the GRT (for network and IES interfaces) to provide increased IPv6 connectivity in a PE-CE environment.

BGPv6 shows an example of a network with 7705 SAR nodes on the CE utilizing BGPv6. The 7705 SAR can also be used on the PE.

Figure 2. BGPv6

CEs are connected via EBGP or, in some cases, IBGP to edge routers, which then connect the CEs across a core BGP network. A privately owned customer network uses IBGP by default. For backup, a third-party network that uses EBGP for connectivity between edge routers and the backup network is used.

Any failures occurring between PEs and CEs are detected with BFD and BGP PIC and resolved with BGP fast reroute.

BGP Add-Paths

Add-paths allows a BGP router to advertise multiple distinct paths for the same prefix/NLRI. BGP add-paths provides a number of potential benefits, including reduced routing churn, faster convergence, and better load sharing. See draft-ietf-idr-add-paths-04.txt, Advertisement of Multiple Paths in BGP for details of the add-paths capabilities advertisement.

This section also contains information about the following topics:

In order for router A to receive multiple paths per NLRI from peer B for a particular address family, they must advertise their BGP capabilities during session setup. Peer router B advertises that it wants to send multiple paths for an address family and router A indicates that it is able to receive multiple paths for the address family.

When the add-paths receive capability for an address family has been negotiated with a peer router, all advertisements and withdrawals of NLRI within that address family by that peer will include a path identifier. Path identifiers have no significance to the receiving peer. If the combination of NLRI and path identifier in an advertisement from a peer is unique and does not match an existing route in the RIB-IN from that peer, then the route is added to the RIB-IN. If the combination of NLRI and path identifier in a received advertisement is the same as an existing route in the RIB-IN from the peer, then the new route replaces the existing one. If the combination of NLRI and path identifier in a received withdrawal matches an existing route in the RIB-IN from the peer, then that route is removed from the RIB-IN. An UPDATE message carrying an IPv4 NLRI with a path identifier is shown in BGP Update Message with Path Identifier for IPv4 NLRI.

Figure 3. BGP Update Message with Path Identifier for IPv4 NLRI

Add-paths are only supported on the base router BGP instance and the EBGP and IBGP sessions it forms with other add-path-capable peers. The ability to send and receive multiple paths per prefix to and from an add-paths peer is configurable per family. The following families support BGP add-path:

  • IPv4

  • label-IPv4

  • VPN-IPv4

  • IPv6

  • VPN-IPv6

Path Selection Mode and Parameters for Multiple Paths to Add-path Peers

The RIB-IN may have multiple paths for a prefix (for example, prefix D). The path selection mode refers to the algorithm used to decide which of these paths to advertise to an add-paths peer. In the current implementation, the 7705 SAR supports only one path selection algorithm, the Add-N algorithm described in draft-ietf-idr-add-paths-guidelines-00.txt, Best Practices for Advertisement of Multiple Paths in BGP. The Add-N algorithm selects the N best overall paths for each prefix, regardless of path type (internal vs. external), degree of difference between the paths or use in forwarding. If this set of N best overall paths includes multiple paths with the same BGP NEXT_HOP, only the best route with a particular NEXT_HOP is advertised and the others are suppressed.

In the 7705 SAR implementation, N is configurable, per address-family, at the BGP global, group, and neighbor levels; N has a minimum value of 1 and a maximum value of 16. For a peer belonging to a group, the path selection parameters are first based on the neighbor configuration for the peer, then the group configuration, then the BGP global configuration.

When add-paths is enabled for the VPN-IPv4 or VPN-IPv6 address family in the base router BGP context, only VPN-IP routes in the base router BGP RIB-IN are considered for advertisement to add-path peers. If a VPRN best route to a destination is a BGP-VPN route imported from the base router and its next-best route is a CE-learned BGP route that would be accepted by the VPRN VRF export policy, this next-best route is not advertised, regardless of the base router’s add-path configuration.

Routing Policy for Multiple Paths

BGP and VRF export policies are applied after path selection is performed. If add-paths is configured to send up to N paths to a peer and an export policy prevents some number (X) of the N best paths for prefix D from being advertised to the peer, then only the remaining (N minus X) best paths are sent.

BGP Route Advertisement Rules for Multiple Paths

Add-paths allows non-best paths to be advertised to a peer, but it still complies with basic BGP advertisement rules such as the IBGP split horizon rule: a route learned from an IBGP neighbor cannot be readvertised to another IBGP neighbor unless the router is configured as a route reflector.

If add-paths is configured to send up to N paths to a peer and some number (X) of the N best paths for D cannot be advertised to the peer due to route advertisement rules, then only the remaining (N minus X) routes are advertised.

BGP Split Horizon

Split horizon refers to the action taken by a router to avoid advertising a route back to the peer from which it was received or to another non-client peer for IBGP. By default, the 7705 SAR applies split-horizon behavior only to routes received from IBGP non-client peers. This split-horizon functionality, which cannot be disabled, prevents routing loops by disabling the advertisement of routes learned from a non-client IBGP peer back to the sending peer or any other non-client peer.

To apply split-horizon behavior to routes learned from RR clients, peers or EBGP peers, the split-horizon command must be configured in the appropriate contexts; it is supported at the global BGP, group, and neighbor levels. When split horizon is enabled on these types of sessions, it only prevents the advertisement of a route back to its originating peer; for example, the 7705 SAR does not prevent the advertisement of a route learned from one EBGP peer back to a different EBGP peer in the same neighbor AS.

Outbound Route Filtering (ORF)

ORF is a mechanism that allows one router, the ORF-sending router, to signal to a peer, the ORF-receiving router, a set of route filtering rules (ORF entries) that the ORF-receiving router should apply to its route advertisements towards the ORF-sending router. The ORF entries are encoded in Route Refresh messages.

The use of ORF for a session must be negotiated — both routers must advertise the ORF capability in their Open messages. The ORF capability describes the address families that support ORF, and for each address family, the ORF types that are supported and the ability to send/receive each type. The 7705 SAR supports ORF type 3, ORF based on extended communities, for the following address families:

  • VPN-IPv4

  • VPN-IPv6

  • MVPN-IPv4

The send and receive capability for ORF is configurable with the send-orf and accept-orf commands, and the setting applies to all supported address families.

ORF type 3 allows a PE router that imports VPN routes with a particular set of route target extended communities to indicate to a peer (for example a route reflector) that it only wants to receive VPN routes that contain one or more of these extended communities. To inform a peer to add or remove a route target extended community, the PE router sends a Route Refresh message to the peer containing an ORF type 3 entry that instructs the peer to either add or remove a permit entry for the 8-byte extended community value.

The type 3 ORF entries that are sent to a peer can be generated dynamically (if no route target extended communities are specified with the send-orf command) or specified statically. Dynamically generated ORF entries are based on the route targets that are imported by all locally configured VPRNs.

A router that has installed ORF entries received from a peer can still apply BGP export policies to the session. BGP export policies overrule ORF entries. If the evaluation of a BGP export policy results in a reject action for a VPN route that matches a permit ORF entry, the route is not advertised.

ORF filtering is efficient; a large number of VPN routes can be filtered faster than using a conventional BGP export policy. In addition to ORF, users can also use BGP Route Target Constrained Route Distribution for dynamic filtering based on route target extended communities. RTC, as discussed below, offers some advantages over ORF.

BGP Route Target Constrained Route Distribution

BGP route target constrained route distribution allows a router to advertise a route target constraint (RTC) route to its peers. A peer receiving an RTC route does not advertise VPN routes back to the router unless they contain a route target extended community that matches one of the received RTC routes. For detailed information about RTC, see the 7705 SAR Services Guide, ‟Route Target Constraint”.

RTC routes are carried using MP-BGP with an AFI value of 1 and SAFI value of 132. The NLRI of an RTC route encodes an Origin AS and a route target extended community using prefix-type encoding with the host bits after the prefix length set to zero.

In order for two routers to exchange route target membership NLRI, they must advertise the corresponding AFI and SAFI to each other during capability negotiation. The use of MP-BGP means route target membership NLRI are propagated, loop-free, within an autonomous system and between autonomous systems, using well-known BGP route selection and advertisement rules.

If there are multiple RTC routes for the same NLRI, the BGP decision process selects one as the best path. The propagation of the best path installs RIB-Out filter rules as it travels from one router to the next, which creates an optimal VPN route distribution tree rooted at the source of the RTC route.

Route target constrained route distribution and outbound route filtering (ORF) both allow routers to advertise which route target extended communities they want to receive in VPN routes from peers. RTC, however, is more widely supported, is simpler to configure, and its distribution scope is not limited to a direct peer.

ORF and RTC are mutually exclusive for a particular BGP session. The CLI does not attempt to block the configuration of both ORF and RTC, but if both capabilities are enabled for a session, the ORF capability will not be included in the Open message sent to the peer.

The capability to exchange RTC routes is advertised when the route-target keyword is added to the family command. RTC is supported for EBGP and IBGP sessions on the base router instance.

When RTC has been negotiated with one or more peers, the 7705 SAR automatically originates and advertises to these peers one RTC route with a prefix length of 96 (the origin AS and route target extended community are fully specified) for every route target imported by a locally configured VPRN or BGP-based Layer 2 VPN, including MVPN-specific route targets.

A router may be configured to send the default RTC route to a group or neighbor with the default-route-target CLI command. This causes the router to generate and send a special RTC route with a prefix length of 0:0:0/0. Sending the default RTC route to a peer conveys a request to receive all VPN routes from that peer. The default RTC route is typically advertised by a route reflector to PE clients. Advertising the default RTC route to a peer does not suppress other more specific RTC routes from being sent to that peer. A received default RTC route is never propagated to other routers.

The advertisement of RTC routes by a route reflector follows special rules as described in RFC 4684. These rules are needed to ensure that RTC routes for the same NLRI that are originated by different PE routers in the same AS are properly distributed within the AS.

When a BGP session comes up and RTC is enabled for the session (both peers advertised the MP-BGP capability), routers delay sending any VPN-IPv4 and VPN-IPv6 routes until either the session has been up for 60 s or the end-of-RIB marker is received for the RTC address family. When the VPN-IPv4 and VPN-IPv6 routes are sent, they are filtered to include only those with a route target extended community that matches an RTC route from the peer.

VPN-IP routes matching an RTC route originated in the local AS are advertised to any IBGP peer that advertises a valid path for the RTC NLRI. Route distribution is not limited only to the IBGP peer advertising the best path. VPN-IP routes matching an RTC route that originated outside the local AS are only advertised to the EBGP or IBGP peer that advertises the best path.

The 7705 SAR does not support an equivalent of BGP Multipath for RTC routes. There is no way to distribute VPN routes across more than one set of inter-AS paths that are nearly equal.

Received RTC routes have no effect on the advertisement on MVPN-IPv4 routes.

Group Configuration and Peers

To enable BGP routing, participating routers must have BGP enabled and be assigned to an autonomous system, and the neighbor (peer) relationships must be specified. A router can belong to only one AS. TCP connections must be established in order for neighbors to exchange routing information and updates. Neighbors exchange BGP Open messages that include information such as AS numbers, BGP versions, router IDs, and hold-time values. Keepalive messages determine if a connection is established and operational. The hold-time value specifies the maximum time BGP will wait between successive messages (either Keepalive or Update) from its peer, before closing the connection.

In BGP, peers are arranged into groups. A group must contain at least one neighbor. A neighbor must belong to a group. Groups allow multiple peers to share similar configuration attributes.

Although neighbors do not have to belong to the same AS, they must be able to communicate with each other. If TCP connections are not established between two neighbors, the BGP peering session will not be established and updates will not be exchanged.

Peer relationships are defined by configuring the IP address of the routers that are peers of the local BGP domain. When neighbor and peer relationships are configured, the BGP peers exchange Update messages to advertise network reachability information.

The 7705 SAR supports BGP peering sessions to both static and dynamic neighbors.

This section contains information about the following topics:

Hierarchical Levels

BGP parameters are initially applied at the global level. These parameters are inherited by the group and neighbor (peer) levels. Parameters can be modified and overridden on a level-specific basis. BGP command hierarchy consists of three levels:

  • global level

  • group level

  • neighbor level

Many of the hierarchical BGP commands can be modified at different levels. The most specific value is used. That is, a BGP group-specific command takes precedence over a global BGP command. A neighbor-specific command takes precedence over a global BGP and group-specific command; for example, if you modify a BGP neighbor-level command default, the new value takes precedence over group- and global-level settings.

Caution: Take care how you use command settings at a lower level that can disable features at a higher level. For example, if the damping command is used to enable damping at the global level and you want it disabled only for a specified neighbor, use the no damping command at the neighbor level only; do not use it the global level also, since this will disable damping for all neighbors within the BGP global instance.

Route Reflection

In a standard BGP configuration, all BGP speakers within an AS must have full BGP mesh to ensure that all externally learned routes are redistributed through the entire AS. IBGP speakers do not readvertise routes learned from one IBGP peer to another IBGP peer. If a network grows, scaling issues could emerge because of the full mesh configuration requirement. Instead of peering with all other IBGP routers in the network, each IBGP router only peers with a router configured as a route reflector.

Route reflection circumvents the full mesh requirement but maintains the full distribution of external routing information within an AS. Route reflection is effective in large networks because it is manageable, scalable, and easy to implement. Route reflection is implemented in autonomous systems with a large internal BGP mesh in order to reduce the number of IBGP sessions required within an AS.

A large AS can be subdivided into smaller ASs, called clusters. Each cluster contains at least one route reflector, which is responsible for redistributing route updates to all clients. Route reflector clients do not need to maintain a full peering mesh between each other. They only require a peering to the route reflectors in their cluster. The route reflectors must maintain a full peering mesh between all non-clients within the AS.

Each route reflector must be assigned a cluster ID and specify which neighbors are clients and which are non-clients to determine which neighbors should receive reflected routes and which should be treated as a standard IBGP peer. Additional configuration is not required for the route reflector, aside from the typical BGP neighbor parameters.

BGP speakers within the AS that are not peers with the route reflector are called non-clients. Non-clients are peers to a route reflector but do not understand the route reflector attributes. Several BGP-speaking routers can peer with a route reflector. A route reflector forms peer connections to other route reflectors.

Fully Meshed BGP Configuration displays a simple configuration with several IBGP 7705 SAR nodes.

When SR-A receives a route from SR-1 (an external neighbor), it must advertise route information to SAR-01, SAR-02, SAR-03, SAR-04, and SAR-05. To prevent loops, IBGP learned routes are not readvertised to other IBGP peers.

Figure 4. Fully Meshed BGP Configuration

When route reflectors are configured, the routers within a cluster do not need to be fully meshed. Fully Meshed BGP Configuration depicts a fully meshed network and BGP Configuration with Route Reflectors depicts the same network but with route reflectors configured to minimize the IBGP mesh between SR-A, SAR-01, SAR-02, and SAR-03. SR-A, configured as the route reflector, is responsible for redistributing route updates to clients SAR-01, SAR-02, and SAR-03. IBGP peering between SAR-01, SAR-02 and SAR-03 is not necessary because even IBGP learned routes are reflected to the route reflector’s clients.

In BGP Configuration with Route Reflectors, SAR-04 and SAR-05 are shown as non-clients of the route reflector. As a result, a full mesh of IBGP peerings must be maintained between SR-A, SAR-04, and SAR-05.

Figure 5. BGP Configuration with Route Reflectors

BGP speakers within an AS that are not configured as reflectors are considered to be client peers. Non-client peers are other routers in the AS. A route reflector enables communication between the clients and non-client peers. Route reflector-to-client peer configurations do not need to be fully meshed, but non-client peers need to be fully meshed within an AS.

A grouping, called a cluster, is composed of a route reflector and its client peers. A cluster ID identifies the grouping unless specific BGP peerings are configured. A cluster’s clients do not share information messages with other peers outside the cluster. Multiple route reflectors can be configured within a cluster for redundancy. A router assumes the role as a route reflector by configuring the cluster cluster-id command. No other command is required unless the operator wants to disable reflection to specific clients.

When a route reflector receives an advertised route, depending on the sender and neighbors (peers), it selects the best path. Routes received from an EBGP peer are advertised unmodified (to retain next-hop information) to all clients and non-client peers in the AS. Routes received from a non-client peer are advertised to all clients in the AS. Routes received from a client are advertised to all clients and non-client peers.

BGP Peer Groups with Dynamic Neighbors

The 7705 SAR supports TCP connections to statically configured and dynamic (unconfigured) BGP peers. A static TCP connection with a remote peer requires the peer to be locally configured as a neighbor using the neighbor ip-address command. Dynamic TCP connections, which are optional and in addition to static connections, use the dynamic-neighbor prefix command to establish a prefix range of potential neighbors from which dynamic connections are allowed, as per RFC 4271 for a BGP speaker.

Enabling the dynamic neighbor functionality makes a BGP speaker more vulnerable to certain security threats and configuration errors; however, on an internal node such as a route reflector these risks may be tolerable, especially if many manual BGP neighbor configurations can be avoided.

The implementation of BGP peer groups with dynamic neighbors is as follows:

  • a configured BGP group supports both static and dynamic peers

  • multiple IPv4 and/or IPv6 prefix ranges can be associated with a peer group to specify allowed sources for incoming TCP connections

    The association of a dynamic peer with a group is based on the source IP address of the TCP connection. If there are multiple overlapping IP prefixes that match the remote IP address, the IP prefix with the longest prefix length is used.

  • outgoing TCP connections are never initiated toward discovered dynamic peers

  • all dynamic peers in a group must use the same session parameters; the parameter values come from the group configuration (such as hold time, keepalive, peer AS, and advertised address families)

  • the maximum number of dynamic peers is configurable per group as well as for the entire BGP instance using the dynamic-neighbor-limit command

  • dynamic peers are supported by the base router and VPRN BGP instances

Fast External Failover

Fast external failover on a group and neighbor basis is supported. For EBGP neighbors, fast external failover controls whether the router drops an EBGP session immediately upon an interface-down event, or whether the BGP session is kept up until the hold-time expires.

When fast external failover is disabled, the EBGP session stays up until the hold-time expires or the interface comes back up again. If the BGP routes become unreachable as a result of the interface going down, they are immediately withdrawn from other peers.

BGP Fast Reroute With Prefix-Independent Convergence

BGP Fast Reroute (FRR) creates an alternate path to support fast rerouting of BGP traffic around failed or unreachable next hops. When BGP FRR is enabled, the system switches to a precalculated alternate path as soon as a failure is detected.

BGP Prefix-Independent Convergence (PIC) is supported on the 7705 SAR and is automatically enabled when a BGP backup path is enabled. With BGP FRR and PIC, alternate paths are precalculated and the FIB is updated with all alternate next hops. When a prefix has a backup path, and its primary paths fail, the affected traffic is rapidly diverted to the backup path without waiting for control plane reconvergence to occur. When many prefixes share the same primary paths, and in some cases also share the same backup path, the time to switch traffic to the backup path can be very fast and is independent of the number of prefixes.

BGP FRR can be enabled in the BGP context or in the VPRN context on either IPv4 or IPv6 prefixes. For information about BGP FRR for VPRNs, see the 7705 SAR Services Guide, ‟BGP Fast Reroute with Prefix-Independent Convergence in a VPRN”.

When BGP FRR is enabled, the control plane attempts to find an eligible backup path for every received IPv4 or IPv6 prefix. In most cases, the backup path is the single best path remaining after the 7705 SAR removes the primary ECMP paths and any paths with the same BGP next hops.

The following scenarios affect backup path selection.

  • A backup path is not calculated for a prefix if the best path is a label-IPv4 route that has been programmed with multiple ECMP next hops through different BGP next hops.

  • For label-IPv4 or prefixes that are readvertised with a new BGP next hop, the programmed backup path is the same for all prefixes that have the same best path and received label, even if the calculated backup path is different for some of the prefixes.

BGP FRR Scenarios  lists the supported BGP FRR scenarios.

Table 2. BGP FRR Scenarios 

Ingress Packet

Primary Route

Backup Route

PIC

IPv4 (ingress PE)

IPv4 route with next hop A resolved by an IPv4 route

IPv4 route with next hop B resolved by an IPv4 route

Yes

IPv4 (ingress PE)

VPN-IPv4 route with next hop A resolved by a GRE, LDP, RSVP, or BGP tunnel

VPN-IPv4 route with next hop B resolved by a GRE, LDP, RSVP or BGP tunnel

Yes

IPv6 (ingress PE)

VPN-IPv6 route with next hop A resolved by a GRE, LDP, RSVP, or BGP tunnel

VPN-IPv6 route with next hop B resolved by a GRE, LDP, RSVP, or BGP tunnel

Yes

IPv6 (ingress PE)

IPv6 route with next hop A resolved by an IPv6 route

IPv6 route with next hop B resolved by an IPv6 route

Yes

MPLS (egress PE)

IPv4 route with next hop A resolved by an IPv4 route

IPv4 route with next hop B resolved by an IPv4 route

Yes

MPLS (egress PE)

IPv4 route with next hop A resolved by an IPv4 route

VPN-IPv4 route with next hop B resolved by a GRE, LDP, RSVP or BGP tunnel

Yes

MPLS (egress PE)

IPv6 route with next hop A resolved by an IPv6 route

VPN-IPv6 route with next hop B resolved by a GRE, LDP, RSVP or BGP tunnel

Yes

BGP FRR Failure Detection and Switchover

When BGP FRR is enabled, the 7705 SAR reroutes traffic onto a backup path based on input from BGP. When a primary path is no longer usable, BGP notifies the IOM and affected traffic is immediately switched to the backup path.

BGP FRR is triggered when:

  • peer tracking is enabled and a peer IP address is unreachable

  • a BFD session associated with the BGP peer goes down

  • a BGP session with a peer is terminated

  • there is no longer any route allowed by the next-hop resolution policy, if configured, that can resolve the BGP next-hop address

  • the LDP tunnel that resolves the next-hop is down. This can occur if there is no longer any IP route that can resolve the FEC, if the LDP session goes down, or if the LDP peer withdraws its label mapping.

  • the RSVP tunnel that resolves the next hop is down. This can occur if a ResvTear message is received, the RESV state times out, or if the outgoing interface fails and is not protected by FRR or a secondary path.

  • the BGP tunnel that resolves the next hop is down. This can occur if the BGP label-IPv4 route is withdrawn by the peer or if it becomes invalid due to an unresolved next hop.

Calculating Backup Paths

Fast reroute is enabled using the BGP backup-path command.

The backup-path command in the base router context is used to control fast reroute on a per-RIB basis (IPv4, label-IPv4, and IPv6). When the command specifies a particular family, BGP attempts to find a backup path for every prefix learned by the associated BGP RIB.

In general, a prefix supports ECMP paths or a backup path, but not both. The backup path is the best path after the primary path and any paths with the same BGP next hop as the primary path have been removed.

Sending of BGP Communities

The capability to explicitly enable or disable the sending of the BGP community attribute to BGP neighbors, other than through the use of policy statements, is supported.

This feature allows an administrator to enable or disable the sending of BGP communities to an associated peer. This feature overrides communities that are already associated with a given route or that may have been added via an export route policy. In other words, even if the export policies leave BGP communities attached to a given route, when the disable-communities feature is enabled, no BGP communities are advertised to the associated BGP peers.

BGP Decision Process

When a BGP router has multiple routes in its RIB-IN, the BGP decision process is responsible for deciding which route is the best. The best path can be used by the local router and advertised to other BGP peers.

Whenever a new route is received, the BGP decision process compares this route to the current best path for the same prefix by making a series of comparisons. The process is used to determine whether the new route should become the new best path.

On the 7705 SAR, the BGP decision process prioritizes received routes based on the following sequence of comparisons. If there is a tie between routes at any step, BGP proceeds to the next step.

  1. Select a valid route over an invalid route.

  2. Select the route with the numerically lowest route-table preference.

  3. Select the route with the highest local preference (LOCAL_PREF).

  4. Select the route with an AIGP metric. If both routes have an AIGP metric, select the route with the lowest sum of:

    1. the AIGP metric value stored with the RIB-IN copy of the route

    2. the route table or tunnel table cost between the calculating router and the BGP next hop in the received route

  5. Select the route with the shortest AS path. This step is skipped if as-path-ignore is configured for the address family.

  6. Select the route with the lowest ORIGIN (IGP < EGP < Incomplete).

  7. Select the route with the lowest MED. Routes with no MED attribute (default MED value of 0) are exempted from this step unless always-compare-med is configured.

  8. Select the route learned from an EBGP peer over a route learned from an IBGP peer.

  9. Select the route with the lowest IGP cost to the next hop.

  10. Select the route with the lowest BGP identifier.

  11. Select the route with the shortest CLUSTER_LIST length.

  12. Select the route with the lowest next-hop IP address.

BGP Route Tunnels

BGP route tunnels can be used to distribute MPLS label mapping information for a particular route, as defined in RFC 3107. When BGP is used to distribute a route, it can also distribute the MPLS label for the same route by piggybacking the label onto the BGP update message.

In a network scenario where two adjacent LSRs are also BGP peers, label distribution can be handled entirely by the BGP update message—no other distribution protocol is required.

In a network scenario where the exterior LSRs are BGP speakers, the LSRs can send MPLS labels to each other along with each route they distribute. The MPLS label is piggybacked onto the BGP update message by using the BGP-4 Multiprotocol Extensions Attribute. The label is encoded in the NLRI field and the SAFI field is used to indicate that the NLRI field contains a label. A labeled route update is only exchanged between BGP speakers supporting AFI/SAFI for MPLS Label Capability.

The 7705 SAR supports the following BGP address families:

  • IPv4

  • VPN-IPv4

  • IPv6

  • VPN-IPv6

  • MVPN-IPv4

  • route-target

  • EVPN

  • label-IPv4

  • label-IPv6

  • BGP-LS

The types of routes that are advertised are indicated by the AFI/SAFI advertised.

BGP speakers that are not adjacent to each other may choose LDP or RSVP-TE tunnels to reach the BGP labeled route next hop. Client applications using BGP tunnels must push two labels (BGP label and LDP/RSVP-TE label) on top of the existing label stack (which will typically include one or more service-specific labels) in order to reach the BGP next hop. The next-hop BGP node can either resolve its own local LDP or RSVP-TE LSPs to reach its next hop.

If BGP speaker nodes are adjacent to each other (for example, ASBRs running an EBGP session) and have exchanged labeled routes, then only the BGP route label is used to forward traffic toward the next hop. If the BGP route tunnel transits through multiple autonomous systems, then each AS segment would have two labels. For the last BGP segment, ASBR may select to have either one (LDP/RSVP-TE) or two (BGP + LDP/RSVP-TE) labels to reach the far end.

This section contains information about the following topics:

Route Reflector Next-Hop-Self for IP-VPNv4/6 Routes over IPv4 LU

As an enhancement to the preceding route distribution scenario, inter-AS option B model-like behavior (as per RFC 4364, BGP/MPLS IP Virtual Private Networks (VPNs)) can be enabled for route reflectors that exchange PE reachability information using IPv4 address family labeled routes. A route reflector acting as an ASBR that receives VPN IPv4 or VPN IPv6 routes from a client over a BGP-labeled tunnel can use next-hop-self to redistribute the VPN routes to another ASBR by means of an IBGP session for the VPN IPv4 or VPN IPv6 address family.

For example (see Route Reflector Next-Hop-Self for VPN IPv4 Routes over IPv4 Labeled Routes):

  • a route reflector (RR1), acting as an ASBR in AS 65001, receives VPN IPv4 routes from PE1 over a BGP-labeled tunnel

  • a route reflector (RR2), acting as an ASBR in AS 65002, receives VPN IPv4 routes from PE2 over a BGP-labeled tunnel

  • the enable-rr-vpn-forwarding command is enabled on RR1, which allows it to distribute VPN IPv4 routes

  • the next-hop-self command is enabled on both RR1 and RR2

  • RR1 has an IBGP session established with RR2. To establish the IBGP session, RR1 must have a local-AS value configured as AS 65002.

When PE2 advertises a VPN IPv4 route to RR2, the route reflector resolves the route to an MPLS tunnel, changes the next hop to itself, advertises the route to RR1, and performs a label swap between the advertised and received labels. RR1 resolves the route via the IPv4 tunnel to RR2. RR1 then changes the next hop to itself, performs a label swap, prepends the local-AS 65002, and readvertises the VPN IPv4 route to PE1.

Figure 6. Route Reflector Next-Hop-Self for VPN IPv4 Routes over IPv4 Labeled Routes

Layer 2 Services and BGP Route Tunnel

An MPLS transport tunnel per VPLS/VLL instance is enabled by an explicit MPLS-SDP configuration for each far-end PE.

BGP Route Tunnel SDP Binding

BGP route tunnel-based SDP binding is allowed for VPLS and VLL services. Any service using BGP SDP must presume a two-label stack to compute the SDP MTU. For more information about SDPs for BGP route tunnels, see the 7705 SAR Services Guide, ‟Service Destination Points (SDPs)”.

BGP Route Tunnel With Multihop EBGP Resolution

Either an RSVP-TE or LDP LSP can be used to resolve the next hop between two ASBR nodes. The transport-tunnel CLI command can be used to select the specific transport LSP method. The mpls option under transport-tunnel enables the option to select either an RSVP-TE LSP or LDP LSP. If the mpls option is selected, an RSVP-TE LSP is considered the higher-priority LSP and its availability is checked first. If an RSVP-TE LSP is not available, then an LDP LSP is selected.

Next-hop Resolution of BGP Labeled Routes to Tunnels

The 7705 SAR always attempts to resolve the next hop of a label-IPv4 or label-IPv6 route. The resolution is attempted as follows. If the first condition does not apply, the 7705 SAR moves to the next, and so on:

  • if the BGP next hop is part of a local subnet, the next hop is resolved by the interface route

  • if there is a static-route entry with a blackhole next hop that matches the BGP next hop, this static route resolves the label-IPv4 or label-IPv6 route

  • if there is a tunnel in the tunnel-table with a destination that matches the BGP next-hop address and the tunnel type is allowed by the label-route-transport-tunnel family label-ipv4 or label-route-transport-tunnel family label-ipv6 command and is the tunnel with the numerically lowest TTM preference to the destination, this tunnel resolves the label-IPv4 or label-IPv6 route

  • if none of the above conditions apply, the label-IPv4 or label-IPv6 is unresolved and invalid

Use the following CLI syntax to configure next-hop resolution of BGP labeled routes.

CLI Syntax:
config>router>bgp>next-hop-res
    label-route-transport-tunnel
            family {vpn |label-ipv4 |label-ipv6}
                resolution {any | filter | disabled}
                resolution-filter
                    [no] ldp
                    [no] rsvp
                    [no] sr-isis
                    [no] sr-ospf
                    [no] sr-te

The label-route-transport-tunnel context provides separate control for the different types of BGP label routes: label-IPv4, label-IPv6, and VPN routes (which includes both VPN-IPv4 and VPN-IPv6 routes). By default, all labeled routes resolve to LDP (even if the preceding CLI commands are not configured in the system).

If the resolution option is set to disabled, the default binding to LDP tunnels resumes. If resolution is set to any, the supported tunnel type selection is based on TTM preference. The order of preference of TTM tunnels is: RSVP, SR-TE, LDP, SR-OSPF, and SR-ISIS.

The rsvp option instructs BGP to search for the best metric RSVP-TE LSP to the address of the BGP next hop. The address can correspond to the system interface or to another loopback used by the BGP instance on the remote node. The LSP metric is provided by MPLS in the tunnel table. If there are multiple RSVP-TE LSPs with the same lowest metric, BGP selects the LSP with the lowest tunnel ID.

The ldp option instructs BGP to search for an LDP LSP with a FEC prefix corresponding to the address of the BGP next hop.

When the sr-isis or sr-ospf option is enabled, an SR tunnel to the BGP next hop is selected in the TTM from the lowest preference IS-IS instance or from OSPF. If multiple instances have the same lowest preference, the lowest-numbered IS-IS instance is selected.

The sr-te option instructs BGP to search for the best metric SR-TE LSP to the address of the BGP next hop. The LSP metric is provided by MPLS in the tunnel table. If there are multiple SR-TE LSPs with the same lowest metric, BGP selects the LSP with the lowest tunnel ID.

If one or more explicit tunnel types are specified using the resolution-filter option, only these tunnel types are selected again following the TTM preference. The resolution command must be set to filter to activate the list of tunnel types configured with the resolution-filter command.

BGP Next-Hop Resolution and Peer Tracking

The 7705 SAR can attach a route policy to the BGP next-hop resolution process and can allow a route policy to be associated with the optional BGP peer-tracking function. These two features are also supported for VPRN BGP service.

BGP next-hop resolution determines the best matching route (or tunnel) for the BGP next-hop address and uses information about this resolving route when running the best-path selection algorithm and programming the forwarding table. Attaching a policy to BGP next-hop resolution provides additional control over which IP routes in the routing table can become resolving routes. Similar flexibility and control is available for BGP peer tracking, which is an optional feature that allows a session with a BGP neighbor to be taken down if there is no IP route to the neighbor address or if the best matching IP route is rejected by the policy.

Use the following CLI syntax to configure next-hop resolution and peer-tracking policies:

CLI Syntax:
config>router>bgp
    next-hop-resolution
        policy policy-name
        no policy
    peer-tracking-policy policy-name
    no peer-tracking-policy

For details, see the ‟Route Policies for BGP Next-Hop Resolution and Peer Tracking” section in the 7705 SAR Router Configuration Guide.

BGP Route Installation in the Route Table

Each BGP RIB that is holding routes (unlabeled IPv4, labeled unicast IPv4, unlabeled IPv6) submits its best path for each prefix to the common IP route table. It is up to the route table to choose the single best of these paths for forwarding to each IP prefix destination. The route table chooses the route by using the BGP decision process. The default preference for BGP routes submitted by the label-IPv4 or label-IPv6 RIBs (which appear in the route table and FIB as having a BGP-LABEL protocol type) can be modified using the label-preference command. The default preference for BGP routes submitted by the unlabeled IPv4 and IPv6 RIBs can be modified by using the preference command.

If a BGP RIB has multiple BGP paths (LOC-RIB routes) for the same IPv4 or IPv6 prefix that qualify as the best path up to a certain point in the comparison process, a certain number of these paths can be submitted to the common IP route table. This functionality is called BGP Multipath and it must be explicitly enabled using the multipath command. The multipath command specifies the maximum number of BGP paths, including the overall best path, that each BGP RIB can submit to the route table for any particular IPv4 or IPv6 prefix. If ECMP, with a limit of n, is enabled in the base router instance, then up to n paths are selected for installation in the IP FIB. In the datapath, traffic matching the IP route is load-shared across the ECMP next-hops based on a per-packet hash calculation.

By default, the hashing is not sticky, meaning that when one or more of the equal-cost BGP next-hops fail, all traffic flows matching the route are potentially moved to new BGP next hops.

In the route table, a BGP path to an IPv4 or IPv6 prefix is a candidate for installation as an ECMP next hop (subject to the path limits of the multipath and ecmp commands) only if it meets all of the following criteria:

  1. it is the overall best BGP path or it is tied with the overall best path up to and including step 12 of the decision process summarized in BGP Decision Process.

  2. compared with other paths with the same BGP NEXT_HOP, it is the best path, based on evaluation of all steps of the BGP decision process

  3. it is the same type of route as the best path and all other paths installed with the multipath command, that is, it came from the same BGP RIB (labeled unicast or unlabeled)

The 7705 SAR also supports a feature called IBGP Multipath. In some topologies, a BGP next hop is resolved by an IP route (for example a static, OSPF, or IS-IS route) that has multiple ECMP next hops. If ibgp-multipath is not configured, only one of these ECMP next hops is programmed as a next hop of the BGP route in the IOM. If ibgp-multipath is configured, the IOM attempts to use all of the ECMP next-hops of the resolving route for forwarding.

Although the name of the ibgp-multipathcommand implies that it is specific to IBGP-learned routes, it applies to routes learned from any multi-hop BGP session, including routes learned from multi-hop EBGP peers.

Note: BGP Multipath and IBGP Multipath are not mutually exclusive and work together. BGP Multipath enables ECMP load-sharing across different BGP next hops (corresponding to different LOC-RIB routes) and IBGP Multipath enables ECMP load-sharing across different IP next hops of IP routes that resolve the BGP next hops.

IBGP Multipath does not control load-sharing of traffic toward a BGP next hop that is resolved by a tunnel, such as when dealing with labeled routes (VPN-IP, label-IPv4, or label-IPv6). When a BGP next hop is resolved by a tunnel that supports ECMP, the load-sharing of traffic across the ECMP next hops of the tunnel is automatic.

BGP Link State

BGP Link State (BGP-LS) is a BGP address family that distributes multi-area or multi-level network IGP topology information to an external server, such as a Path Computation Element (PCE) server. The external traffic engineering database can use this information when calculating optimal paths. Through the use of one or two BGP-LS speakers per area (for OSPF) or level (for IS-IS), the external PCE server can receive full topology information for the entire network. By using BGP-LS, IGP link-state information can be extracted from different portions of the network (areas or levels) without the need for direct adjacencies. This allows the external server to develop a complete end-to-end view of the network topology and traffic engineering information.

Example of a BGP-LS Network shows an example of a BGP-LS network.

Figure 7. Example of a BGP-LS Network

Supported BGP-LS Components

The following BGP-LS components are supported.

Protocol-ID:

  • IS-IS Level 1

  • IS-IS Level 2

  • OSPFv2

NLRI types:

  • Node

  • Link

  • IPv4 Prefix

Node Descriptor TLVs:

  • 512 — Autonomous System

  • 513 — BGP-LS Identifier

  • 514 — OSPF Area-ID

  • 515 — IGP Router-ID

Node Attribute TLVs:

  • 1024 — Node Flag Bits (O and B bits supported)

  • 1028 — IPv4 Router-ID of Local Node (IS-IS only)

  • Segment Routing:

    • 1034 — SR Capabilities (IS-IS only)

    • 1035 — SR Algorithm (IS-IS only)

Link Descriptor TLVs:

  • 258 — Link Local/Remote Identifiers

  • 259 — IPv4 interface address

  • 260 — IPv4 neighbor address

Link Attribute TLVs:

  • 1028 — IPv4 Router-ID of Local Node (IS-IS only)

  • 1088 — Administrative group (color)

  • 1089 — Maximum link bandwidth

  • 1090 — Maximum reservable link bandwidth

  • 1091 — Unreserved bandwidth

  • 1092 — TE Default Metric

  • 1095 — IGP Metric

  • 1096 — Shared Risk Link Group

  • Segment Routing:

    • 1099 — Adjacency Segment Identifier

    • 1100 — LAN Adjacency Segment Identifier

Prefix Descriptor TLVs:

  • 264 — OSPF Route Type (Intra-Area and Inter-Area only)

  • 265 — IP Reachability Information

Prefix Attribute TLVs:

  • 1152 — IGP Flags (D flag only)

  • 1155 — Prefix Metric

  • Segment Routing:

    • 1158 — Prefix SID

    • 1159 — Range (prefix-SID and sub-TLV only)

    • 1170 — Prefix Attribute Flags (OSPF only)

Command Interactions and Dependencies

This section highlights the BGP command interactions and dependencies that are important for configuration or operational maintenance of 7705 SAR routers. Topics covered in this section are:

This information can be found in the BGP Command Reference, which provides detailed descriptions of the configuration commands.

Changing the Autonomous System Number

If the AS number is changed on a router with an active BGP instance, the new AS number will not be used until the BGP instance is restarted either by administratively disabling or enabling the BGP instance or by rebooting the system with the new configuration.

Note: The 7705 SAR supports 4-byte AS numbers, as defined in RFC 4893, BGP Support for Four-octet AS Number Space. This allows up to 4 294 967 295 unique AS numbers.

Changing the Local AS Number

Changing the local AS of an active BGP instance:

  • at the global level — causes the BGP instance to restart with the new local AS number

  • at the group level — causes BGP to re-establish the peer relationships with all peers in the group with the new local AS number

  • at the neighbor level — causes BGP to re-establish the peer relationship with the new local AS number

Changing the Router ID at the Configuration Level

If you configure a new router ID in the config>router-id context, protocols are not automatically restarted with the new router ID. The next time a protocol is initialized or reinitialized, the new router ID is used. An interim period of time can occur when different protocols use different router IDs.

Hold Time and Keepalive Timer Dependencies

The BGP hold time specifies the maximum time BGP will wait between successive messages (either Keepalive or Update) from its peer, before closing the connection. This configuration parameter can be set at three levels. The most specific value is used:

  • global level — applies to all peers

  • group level — applies to all peers in the group

  • neighbor level — only applies to the specified peer

Although the keepalive time can be user-specified, the configured keepalive timer is overridden by the value of hold time under the following circumstances.

  • If the hold time specified is less than the configured keepalive time, then the operational keepalive time is set to one third of the specified hold time; the configured keepalive time is unchanged.

  • If the hold time is set to zero, then the operational value of the keepalive time is set to zero; the configured keepalive time is unchanged. This means that the connection with the peer will be up permanently and no keepalive packets are sent to the peer.

If the hold time or keepalive values are changed, the changed timer values take effect when the new peering relationship is established. Changing the values causes the peerings to restart. The changed timer values are used when renegotiating the peer relationship.

Import and Export Route Policies

Import and export route policy statements are specified for BGP at the global, group, and neighbor level. Up to five unique policy statement names can be specified in the command line per level. The most specific command is applied to the peer. Defining the policy statement name is not required before being applied. Policy statements are evaluated in the order in which they are specified within the command context until the first matching policy statement is found.

The import and export policies configured at different levels are not cumulative. The most specific value is used. An import or export policy command specified at the neighbor level takes precedence over the same command specified at the group or global level. An import or export policy command specified at the group level takes precedence over the same command specified at the global level.

AS Override

BGP-4 Explicit AS Override simplifies the use of the same AS number (ASN) across multiple RFC 2547 VPRN sites.

The Explicit AS Override feature can be used in VPRN scenarios where a customer is running BGP as the PE-CE protocol and some or all of the CE locations are in the same Autonomous System (AS). Without this feature, two sites in the same AS would not be able to reach each other directly since there is an apparent loop in the AS path.

With AS Override enabled on an EBGP session on a PE node, the service provider network can rewrite the AS path — overriding the customer ASN with its own ASN — as routes are advertised to other sites within the same VPRN.

TCP MD5 Authentication

The operation of a network can be compromised if an unauthorized system is able to form or hijack a BGP session and inject control packets by falsely representing itself as a valid neighbor. This risk can be mitigated by enabling TCP MD5 authentication on one or more of the sessions. When TCP MD5 authentication is enabled on a session, every TCP segment exchanged with the peer includes a TCP option (19) containing a 16-byte MD5 digest of the segment (more specifically the TCP/IP pseudo-header, TCP header, and TCP data). The MD5 digest is generated and validated using an authentication key that must be known to both sides. If the received digest value is different from the locally computed one, the TCP segment is dropped, thereby protecting the router from a spoofed TCP segment.

The TCP Enhanced Authentication Option, as specified in draft-bonica-tcpauth-05.txt, Authentication for TCP-based Routing and Management Protocols, is a TCP extension that enhances security for BGP, LDP, and other TCP-based protocols. It extends the MD5 authentication option to include the ability to change keys in a BGP or LDP session seamlessly without tearing down the session, and allows for stronger authentication algorithms to be used. It is intended for applications where secure administrative access to both endpoints of the TCP connection is normally available.

TCP peers can use this extension to authenticate messages passed between one another. This strategy improves upon the practice described in RFC 2385, Protection of BGP Sessions via the TCP MD5 Signature Option. Using this new strategy, TCP peers can update authentication keys during the lifetime of a TCP connection. TCP peers can also use stronger authentication algorithms to authenticate routing messages.

TCP enhanced authentication uses keychains that are associated with every protected TCP connection.

Keychains are configured in the config>system>security>keychain context. For more information about configuring keychains, see the 7705 SAR System Management Guide, ‟TCP Enhanced Authentication and Keychain Authentication”.

TTL Security

TTL security provides protection for EBGP peering sessions against CPU utilization-based attacks such as denial of service (DoS) attacks. This feature is supported for directly connected peering sessions and for multihop EBGP peering sessions. The BGP session can be over router interfaces, over spoke-SDP terminated VPRN interfaces, SAP interfaces, and loopback interfaces, and over IPSec interface tunnels.

TTL security is most important for EBGP PE-CE sessions because CE devices can be multiple hops away, which adds a higher level of risk. TTL security provides a mechanism to better ensure the validity of BGP sessions from the CE device.

TTL security is configured at the group or neighbor level. The ttl-security command sets the minimum TTL that will be accepted in a BGP peering session and checks the TTL of the packets received. For multihop peering sessions, the multihop command sets the TTL in the IP header of egress BGP packets sent to a terminating peer that is several hops away.

When TTL security is configured, the network processor must inspect BGP packets. The value in the TTL field of received IP packets is compared with the TTL security value that is configured locally for each EBGP peering session. If the value in the TTL field of the incoming IP packet is greater than or equal to the configured minimum TTL value, the IP packet is accepted and processed normally. If the TTL value is less than the configured value, the packet is discarded.

Advertise-Inactive

BGP does not allow a route to be advertised unless it is the best path in the RIB and an export policy allows the advertisement.

In some cases, it may be useful to advertise the best BGP path to peers despite the fact that it is inactive; for example, if there are one or more lower-preference non-BGP routes to the same destination and one of these other routes is the active route. This flexibility is supported using the advertise-inactive and add-path commands.

As a global BGP configuration option, the advertise-inactive command applies to all IPv4, IPv6, label-IPv4, and label-IPv6 routes and all sessions that advertise these routes. If the command is configured and the best BGP path is inactive, it is automatically advertised to every peer unless rejected by a BGP export policy.

Advertise-Inactive, Add-Paths, and Export Policy Interaction

This section describes the interaction between the BGP advertise-inactive, add-paths, and export policy commands. The 7705 SAR allows the policy-based export of an active and installed route to a peer when the local router has BGP advertise-inactive enabled in its configuration.

The following behavior for advertise-inactive occurs when an active, non-BGP route (route A) exists in the routing table and is accepted by the configured BGP export policy.

  • If the add-paths send-limit is set to n paths, then BGP advertises n paths that are accepted by the export policy and have diverse next hops, whether advertise-inactive is enabled or disabled.

    For example, if n=3, then routes A, B1, and B2 are advertised (route A is counted as one of the paths), as long as route A is accepted by the export policy. Otherwise, routes B1, B2 and B3 are advertised.

  • If add-paths is disabled and advertise-inactive is enabled, then BGP advertises one active non-BGP route if the route is accepted by the export policy. Otherwise, BGP advertises the best BGP route that is accepted by the policy.

    For example, BGP advertises either route A or route B1, depending on the export policy.

Configuration Notes

This section describes BGP configuration guidelines and caveats.

General

  • Before BGP can be configured, the router ID (a valid host address, not the MAC address default) and autonomous system global parameters must be configured.

  • BGP instances must be explicitly created on each BGP peer. There are no default BGP instances on a 7705 SAR.

BGP Defaults

The following list summarizes the BGP configuration defaults.

  • By default, the 7705 SAR is not assigned to an AS.

  • A BGP instance is created in the administratively enabled state.

  • A BGP group is created in the administratively enabled state.

  • A BGP neighbor is created in the administratively enabled state.

  • No BGP router ID is specified. If no BGP router ID is specified, BGP uses the router system interface address.

  • The 7705 SAR BGP timer defaults are the values recommended in IETF drafts and RFCs (see BGP MIB Notes).

  • If no import route policy statements are specified, then all BGP routes are accepted.

  • If no export route policy statements specified, then all BGP routes are advertised and non-BGP routes are not advertised.

BGP MIB Notes

The 7705 SAR implementation of the RFC 1657 MIB variables listed in 7705 SAR and IETF MIB Variations differs from the IETF MIB specification.

Table 3. 7705 SAR and IETF MIB Variations

MIB Variable

Description

RFC 1657 Allowed Values

7705 SAR Allowed Values

bgpPeerMinASOrig-intionInterval

Time interval in seconds for the MinASOriginationInterval timer. The suggested value for this timer is 15 s.

1 to 65535

2 to 255

bgpPeerMinRouteAd-vertisementInterval

Time interval in seconds for the MinRouteAdvertisementInterval timer. The suggested value for this timer is 30 s.

1 to 65535

2 to 255

If SNMP is used to set a value of X to the MIB variable in MIB Variable with SNMP, there are three possible results:

Table 4. MIB Variable with SNMP

Condition

Result

X is within IETF MIB values

and

X is within 7705 SAR values

SNMP set operation does not return an error MIB variable set to X

X is within IETF MIB values

and

X is outside 7705 SAR values

SNMP set operation does not return an error

MIB variable set to ‟nearest” 7705 SAR supported value (for example, 7705 SAR range is 2 to 255 and X = 65535, MIB variable will be set to 255)

Log message generated

X is outside IETF MIB values

and

X is outside 7705 SAR values

SNMP set operation returns an error

When the value set using SNMP is within the IETF allowed values and outside the 7705 SAR values as specified in 7705 SAR and IETF MIB Variations and MIB Variable with SNMP, a log message is generated. The log messages that display are similar to the following log messages.

Log Message for setting bgpPeerMinASOriginationInterval to 65535

576 2006/11/12 19:45:48 [Snmpd] BGP-4-bgpVariableRangeViolation: Trying to set bgpPeerMinASOrigInt to 65535 - valid range is [2-255] - setting to 255:

Log Message for setting bgpPeerMinASOriginationInterval to 1

594 2006/11/12 19:48:05 [Snmpd] BGP-4-bgpVariableRangeViolation: Trying to set bgpPeerMinASOrigInt to 1 - valid range is [2-255] - setting to 2:

Log Message for setting bgpPeerMinRouteAdvertisementInterval to 256

535 2006/11/12 19:40:53 [Snmpd] BGP-4-bgpVariableRangeViolation: Trying to set bgpPeerMinRouteAdvInt to 256 - valid range is [2-255] - setting to 255:

Log Message for setting bgpPeerMinRouteAdvertisementInterval to 1

566 2006/11/12 19:44:41 [Snmpd] BGP-4-bgpVariableRangeViolation: Trying to set bgpPeerMinRouteAdvInt to 1 - valid range is [2-255] - setting to 2

BGP Configuration Overview

Preconfiguration Requirements

Before BGP can be implemented, the following entities must be configured:

  • the autonomous system (AS) number for the router

    An AS number is a globally unique value that associates a router with a specific autonomous system. This number is used to exchange exterior routing information with neighboring ASs and as an identifier of the AS itself. Each router participating in BGP must have an AS number specified.

    In order to implement BGP, the AS number must be specified in the config>router context.

  • the router ID

    The router ID is the IP address of the local router. The router ID identifies a packet’s origin. The router ID must be a valid host address.

BGP Hierarchy

BGP is configured in the config>router>bgp context. Three hierarchical levels are included in BGP configurations:

  • global level

  • group level

  • neighbor level

Commands and parameters configured at the global level are inherited by the group and neighbor levels, although parameters configured at the group and neighbor levels take precedence over global configurations.

Internal and External BGP Configurations

A BGP domain is composed of ASs that share network reachability information. Network reachability information is shared throughout the BGP domain by BGP speakers. BGP speakers can belong to the same or different AS. BGP supports two types of routing information exchanges.

  • Internal BGP (IBGP) is used within an AS. An IBGP speaker peers to the same AS and typically does not share a subnet. Neighbors (peers) do not have to be directly connected to each other. Since IBGP neighbors are not required to be directly connected, IBGP uses the IGP path (the IP next hop learned from the IGP) to reach an IBGP neighbor for its peering connection.

    The 7705 SAR supports IBGP — for MP-BGP purposes — only within the router context.

  • External BGP (EBGP) is used between ASs. EBGP speakers peer to different ASs and typically share a subnet. In an external group, the next hop is dependent upon the interface shared between the external peer and the local one. The multihop command must be specified if an EBGP peer is more than one hop away from the local router. The next hop to the peer must be configured so that the two EBGP speakers can establish a BGP session.

    The 7705 SAR supports EBGP within the router context and VPRN context. For information about configuring EBGP within the VPRN context, see the 7705 SAR Services Guide, ‟VPRN Services”.

BGP Route Reflectors

In a standard BGP configuration, all BGP speakers within an AS must have a full BGP mesh to ensure that all externally learned routes are redistributed through the entire AS. IBGP speakers do not readvertise routes learned from one IBGP peer to another IBGP peer. If a network grows, scaling issues could emerge because of the full mesh configuration requirement. Route reflection circumvents the full mesh requirement but still maintains the full distribution of external routing information within an AS.

Autonomous systems using route reflection arrange BGP routers into groups called clusters. Each cluster contains at least one route reflector that is responsible for redistributing route updates to all clients. Route reflector clients do not need to maintain a full peering mesh between each other. They only require a peering to the route reflectors in their cluster. The route reflectors must maintain a full peering mesh between all non-clients within the AS.

Each route reflector must be assigned a cluster ID and specify which neighbors are clients and which are non-clients to determine which neighbors should receive reflected routes and which should be treated as a standard IBGP peer. Additional configuration is not required for the route reflector except for the typical BGP neighbor parameters.

Route Reflection Network Diagram Example illustrates an autonomous system with clusters.

Figure 9. Route Reflection Network Diagram Example

The following configuration example shows the minimum BGP configuration for routers in Cluster 1.1.1.1, shown in Route Reflection Network Diagram Example.

ALU-A
    config router bgp
        group cluster1
            peer-as 100
            cluster 1.1.1.1
            neighbor 10.2.2.2
            exit
            neighbor 10.3.3.3
            exit
            neighbor 10.4.4.4
            exit
        exit
        group RRs
            peer-as 100
            neighbor 10.5.5.5
            exit
            neighbor 10.9.9.9
            exit
        exit
    exit
ALU-B
    config router bgp
        group cluster1
            peer-as 100
            neighbor 10.1.1.1
            exit
        exit
  exit
ALU-C
    config router bgp
        group cluster1
            peer-as 100
            neighbor 10.1.1.1
            exit
        exit
    exit
ALU-D
    config router bgp
        group cluster1
            peer-as 100
            neighbor 10.1.1.1
            exit
        exit
    exit

Basic BGP Configuration

This section provides information to configure BGP and configuration examples of common configuration tasks. The minimum BGP parameters that must be configured are:

  • an autonomous system number for the router

  • a router ID

  • a BGP peer group

  • a BGP neighbor with which to peer

  • a BGP peer-AS that is associated with the above peer

Note: If a new or different router ID value is entered in the BGP context, the new value takes precedence and overwrites the router-level router ID.

The BGP configuration commands have three primary configuration levels:

  • global configuration (config>router>bgp)

  • BGP group configuration (config>router>bgp>group)

  • BGP neighbor configuration (config>router>bgp>group>neighbor)

Within the three levels, many of the configuration commands are repeated. For the repeated commands, the command that is most specific to the neighboring router is in effect; that is, neighbor settings have precedence over group settings, which have precedence over BGP global settings.

The following is an example of a configuration that includes the parameters in the list above. The other parameters shown below are optional:

info
#--------------------------------------------------
echo "IP Configuration"
#--------------------------------------------------
...
    autonomous-system 200
    router-id 10.10.10.103
#--------------------------------------------------
...
#--------------------------------------------------
echo "BGP Configuration"
#--------------------------------------------------
    bgp
        graceful-restart
        exit
        cluster 0.0.0.100
        damping
        export "direct2bgp"
        router-id 10.0.0.12
        group "Group1"
            connect-retry 20
            damping
            hold-time 90
            keepalive 30
            local-preference 100
            multihop 3
            remove-private
            peer-as 200
            ttl-security 10
            neighbor 10.0.0.8
                connect-retry 20
                damping
                hold-time 90
                keepalive 30
                local-address 10.0.0.12
                multihop 3
                passive
                preference 99
                peer-as 200
                ttl-security 10
            exit
        exit
        group "Group2"
            connect-retry 20
            damping
            hold-time 90
            keepalive 30
            local-preference 100
            remove-private
            peer-as 200
            neighbor 10.0.3.10
                description "To_Router C - IBGP Peer"
                connect-retry 20
                damping
                hold-time 90
                keepalive 30
                peer-as 200
            exit
        exit
        group "Group3"
            connect-retry 20
            damping
            hold-time 30
            keepalive 30
            local-preference 100
            peer-as 200
            neighbor 10.0.0.15
                description "To_Router E - IBGP Peer"
                connect-retry 20
                damping
                hold-time 90
                keepalive 30
                local-address 10.0.0.12
                peer-as 200
            exit

Common Configuration Tasks

This section provides a brief overview of the tasks that must be performed to configure BGP and provides the CLI commands. In order to enable BGP, one AS must be configured and at least one group must be configured that includes neighbor (system or IP address) and peering information (AS number).

BGP is configured hierarchically; the global level applies to all peers, the group level applies to all peers in a group, and the neighbor level only applies to a specified peer. By default, group members inherit the group’s configuration parameters, although a parameter can be modified on a per-member basis without affecting the group-level parameters.

Many of the hierarchical BGP commands can be used at different levels. The most specific value is used. That is, a BGP group-specific command takes precedence over a global BGP command. A neighbor-specific command takes precedence over a global BGP or group-specific command.

All BGP instances must be explicitly created on each 7705 SAR. Once created, BGP is administratively enabled.

Configuration planning is essential to organize ASs and the 7705 SARs within the ASs, and to determine the internal and external BGP peering. To configure a basic autonomous system, perform the following tasks.

  1. Prepare a plan detailing the autonomous systems, the 7705 SAR belonging to each group, group names, and peering connections.

  2. Associate each 7705 SAR with an autonomous system number.

  3. Configure each 7705 SAR with a router ID.

  4. Associate each 7705 SAR with a peer group name.

  5. Specify the local IP address that will be used by the group or neighbor when communicating with BGP peers.

  6. Specify neighbors.

  7. Specify the autonomous system number associated with each neighbor.

Creating an Autonomous System

Before BGP can be configured, the autonomous system must be configured. In BGP, routing reachability information is exchanged between autonomous systems (ASs). An AS is a group of networks that share routing information. The autonomous-system command associates an autonomous system number with the 7705 SAR being configured. A 7705 SAR can only belong to one AS. The autonomous-system command is configured in the config>router context.

Note: The 7705 SAR supports 4-byte AS numbers, as defined in RFC 4893, BGP Support for Four-octet AS Number Space. This allows up to 4 294 967 295 unique AS numbers.

Use the following CLI syntax to associate a 7705 SAR with an autonomous system:

CLI Syntax:
config>router# autonomous-system as-number

The following example displays autonomous system configuration command usage:

Example:
config>router# autonomous-system 100

The following example displays the autonomous system configuration:

ALU-B>config>router# info
#------------------------------------------
# IP Configuration
#------------------------------------------
    interface "system"
        address 10.10.10.104/8
    exit
    interface "to-103"
        address 10.0.0.104/8
        port 1/1/1
    exit
    autonomous-system 100
#------------------------------------------
ALU-B>config>router#

Configuring a Router ID

In BGP, routing information is exchanged between autonomous systems. The BGP router ID, expressed as an IP address, uniquely identifies the router. It can be set to be the same as the loopback address.

If a new or different router ID value is entered in the BGP context, the new router ID value is used instead of the router ID configured on the router level, system interface level, or inherited from the MAC address. The router-level router ID value remains intact.

A router ID can be derived by:

  • defining the value in the config>router context, using the router-id command

  • defining the system interface in the config>router>interface ip-int-name context

  • inheriting the last four bytes of the MAC address

  • defining the value within the BGP protocol level. The router ID can be defined in the config>router>bgp context, using the router-id command, and is only used within BGP.

When configuring a new router ID, protocols are not automatically restarted with the new router ID. The next time a protocol is initialized or reinitialized, the new router ID is used. An interim period of time can occur when different protocols use different router IDs. To force the new router ID, issue the shutdown and no shutdown commands for each protocol that uses the router ID or restart the entire router.

Use the following CLI syntax to configure the router ID:

CLI Syntax:
config>router# router-id ip-address

The following example displays router ID configuration command usage:

Example:
config>router# router-id 10.10.10.104

The following example displays the router ID configuration:

ALU-B>config>router# info
----------------------------------------------
# IP Configuration
#------------------------------------------
    interface "system"
        address 10.10.10.104/8
    exit
    interface "to-103"
        address 10.0.0.104/8
        port 1/1/1
    exit
    autonomous-system 100
    router-id 10.10.10.104
#------------------------------------------
ALU-B>config>router#

BGP Components

This section describes how to configure the following BGP attributes:

Configuring BGP

Once the BGP protocol instance is created, the no shutdown command is not required since BGP is administratively enabled upon creation. Minimally, to enable BGP on a router, you must associate an autonomous system number for the router, have a preconfigured router ID or system interface, create a peer group, neighbor, and associate a peer AS number. There are no default groups or neighbors. Each group and neighbor must be explicitly configured.

All parameters configured for BGP are applied to the group and are inherited by each peer, but a group parameter can be overridden on a specific basis. BGP command hierarchy consists of three levels:

  • the global level

  • the group level

  • the neighbor level

For example:

CLI Syntax:
config>router# bgp 	   (global level)
    group 	           (group level)
        neighbor 	   (neighbor level)
Note: Careful planning is essential to implement commands that can affect the behavior of global, group, and neighbor levels. Because the BGP commands are hierarchical, analyze the values that can disable features on a particular level.

The following example displays the basic BGP configuration:

ALU-B>config>router# info
#------------------------------------------
# BGP Configuration
#------------------------------------------
# BGP
#------------------------------------------
    bgp
    exit
#------------------------------------------
ALU-B>config>router#

Configuring Group Attributes

A group is a collection of related BGP peers. The group name should be a descriptive name for the group. Follow your group naming and ID naming conventions for consistency and to help when troubleshooting faults. All parameters configured for a peer group are applied to the group and are inherited by each peer (neighbor), but a group parameter can be overridden on a specific neighbor-level basis. To configure BGP dynamic peers, see Configuring a BGP Peer Group with Dynamic Neighbors.

The following example displays group configuration command usage:

Example:
config>router# bgp
config>router>bgp# group headquarters1
config>router>bgp>group# description ‟HQ execs”
config>router>bgp>group# multihop 3
config>router>bgp>group# med-out 100
config>router>bgp>group# ttl-security 10
config>router>bgp>group# local-address 10.0.0.104
config>router>bgp>group# disable-communities standard
config>router>bgp>group# exit

The following example displays the BGP group configuration:

ALU-B>config>router>bgp# info
----------------------------------------------
...
    group "headquarters1"
        description "HQ execs"
        multihop 3
        med-out 100
        local-address 10.0.0.104
        disable-communities standard
        ttl-security 10
        exit
    exit
...
----------------------------------------------

Configuring Neighbor Attributes

After you create a group name and assign options, add neighbors within the same autonomous system to create IBGP connections. All parameters configured for the peer group level are applied to each neighbor, but a group parameter can be overridden on a specific neighbor basis.

The following example displays neighbor configuration command usage:

Example:
config>router# bgp
config>router>bgp# group headquarters1
config>router>bgp>group# neighbor 10.0.0.5
config>router>bgp>group# multihop 3
config>router>bgp>group# peer-as 100 
config>router>bgp>group# passive
config>router>bgp>group# ttl-security 10
config>router>bgp>group# exit
config>router>bgp>group# neighbor 10.10.10.6
config>router>bgp>group# multihop 255
config>router>bgp>group# med-out 100
config>router>bgp>group# peer-as 100 
config>router>bgp>group# exit
config>router>bgp>group# neighbor 10.10.10.7
config>router>bgp>group>neighbor$ hold-time 90
config>router>bgp>group>neighbor$ keepalive 30
config>router>bgp>group>neighbor$ local-preference 170
config>router>bgp>group# multihop 255
config>router>bgp>group# med-out 100
config>router>bgp>group>neighbor$ peer-as 100 
config>router>bgp>group>neighbor$ exit
config>router>bgp>group# neighbor 10.10.10.8
config>router>bgp>group>neighbor$ hold-time 90
config>router>bgp>group>neighbor$ keepalive 30
config>router>bgp>group>neighbor$ local-preference 100
config>router>bgp>group>neighbor$ min-route-advertisement 30
config>router>bgp>group>neighbor$ preference 170
config>router>bgp>group# multihop 255
config>router>bgp>group# med-out 100
config>router>bgp>group>neighbor$ peer-as 100 
config>router>bgp>group>neighbor$ exit
config>router>bgp>group# exit

The following example displays neighbors configured in group ‟headquarters1”.

ALU-B>config>router>bgp# info
----------------------------------------------
...
    group "headquarters1"
        description "HQ execs"
        local-address 10.0.0.104
        disable-communities standard extended
        neighbor 10.0.0.5
            multihop 3 
            med-out 100 
            peer-as 100 
            passive    
            ttl-security 10    
        exit
        neighbor 10.0.0.106
            peer-as 100 
        exit
        neighbor 10.0.0.107
            hold-time 90
            keepalive 30
            local-preference 170
            multihop 255 
            med-out 100 
            peer-as 100 
        exit
        neighbor 10.0.0.220
            hold-time 90
            keepalive 30
            min-as-origination 15
            local-preference 100
            preference 170
            multihop 255 
            med-out 100 
            peer-as 100 
        exit
    exit
...
----------------------------------------------
ALU-B>config>router>bgp#

Configuring BGP Address Families

Routers advertise their BGP capabilities during session setup. The 7705 SAR supports several address families. One or more address families can be specified in a single command. To add an address family to the currently configured families, re-issue the command by including the current families in addition to any new family.

Use the following CLI syntax to configure BGP address family parameters:

CLI Syntax:
config>router router-name
    bgp 
        family [ipv4] [vpn-ipv4] [ipv6] [vpn-ipv6] [mvpn-ipv4] [route-target] [evpn] [label-ipv4] [label-ipv6] [bgp-ls] 
        group name
            family [ipv4] [vnp-ipv4] [ipv6] [vpn-ipv6] [mnvp-ipv4] [route-target] [evpn] [label-ipv4] [label-ipv6] [bgp-ls] 
            neighbor ip-address
                family [ipv4] [vnp-ipv4] [ipv6] [vpn-ipv6] [mnvp-ipv4] [route-target] [evpn] [label-ipv4] [label-ipv6] [bgp-ls]

In the display example below, the mvpn-ipv4 address family is added to the BGP group to communicate auto-discovery routes and C-multicast signaling.

#--------------------------------------------------
echo "BGP Configuration"
#--------------------------------------------------
        bgp
            group "MVPN-BGP"
                family ipv4 vpn-ipv4 mvpn-ipv4
                peer-as 65000
                neighbor 10.10.10.125
                exit
                neighbor 10.10.10.127
                exit
            exit
            no shutdown
        exit
#--------------------------------------------------

Configuring Route Reflection

Route reflection can be implemented in autonomous systems with a large internal BGP mesh to reduce the number of IBGP sessions required. One or more routers can be selected to act as focal points for internal BGP sessions. Several BGP speaking routers can peer with a route reflector. A route reflector forms peer connections to other route reflectors. A router assumes the role as a route reflector by configuring the cluster cluster-id command. No other command is required unless you want to disable reflection to specific peers.

If you configure the cluster command at the global level, then all subordinate groups and neighbors are members of the cluster. The route reflector cluster ID is expressed in dotted- decimal notation. The ID should be a significant topology-specific value. No other command is required unless you want to disable reflection to specific peers.

If a route reflector client is fully meshed, the disable-client-reflect command can be enabled to stop the route reflector from reflecting redundant route updates to a client.

The following example displays route reflection configuration command usage:

Example:
config>router# bgp
config>router>bgp# cluster 0.0.0.100
config>router>bgp# group ‟Santa Clara”
config>router>bgp>group$ local-address 10.0.0.103
config>router>bgp>group# neighbor 10.0.0.91
config>router>bgp>group>neighbor$ peer-as 100
config>router>bgp>group>neighbor# exit
config>router>bgp>group# neighbor 10.0.0.92
config>router>bgp>group>neighbor$ peer-as 100
config>router>bgp>group>neighbor# exit
config>router>bgp>group# neighbor 10.0.0.93
config>router>bgp>group>neighbor$ disable-client-refl
config>router>bgp>group>neighbor# peer-as 100
config>router>bgp>group>neighbor# exit

The following example displays a route reflection configuration:

ALU-B>config>router>bgp# info
---------------------------------------------
    cluster 0.0.0.100
    group "Santa Clara"
        local-address 10.0.0.103
        neighbor 10.0.0.91
            peer-as 100
        exit
        neighbor 10.0.0.92
            peer-as 100
        exit
        neighbor 10.0.0.93
            disable-client-reflect
            peer-as 100
        exit
    exit
---------------------------------------------
ALU-B>config>router>bgp#

Configuring a BGP Peer Group with Dynamic Neighbors

The dynamic-neighbor command allows any router within the configured IP prefix range to establish BGP peering sessions with other routers in the prefix range without any manual intervention.

A BGP neighbor session is considered dynamic if its setup is triggered by an incoming TCP connection that does not match the IP address of any static (configured) neighbor. A dynamic BGP session is always associated with one BGP group, as is the case for statically configured peers.

For a base router BGP group to have dynamic sessions, one or more prefix command entries must be added under the config>router>bgp>group>dynamic-neighbor context. There is no limit on the number of prefix entries per group or overall.

The CLI blocks completely overlapping prefix entries in the same routing instance (that is, entries with the same address and same prefix length). Partially overlapping entries are allowed; for example, 10.0.0.0/8 and 10.10.0.0/16.

For a dynamic session to come up, its source IP address must match at least one prefix entry. The dynamic session is associated with the entry—and consequently, the group—having the longest prefix match for the IP address. When a dynamic session has been set up, changes to the neighbor may occur and are handled as follows:

  • when a prefix already exists in a group and a new longer prefix entry is added to the same group, and if the session that already exists still matches on the newly prefix match, the session remains established and is not taken down

  • when a prefix already exists in a group and a new longer prefix entry is added to a different group, and if the session that already exists now matches on the newly added prefix in the different group, the session is taken down in order to apply the new group parameters to the new session when it gets established

  • when a new static neighbor is configured using the neighbor command in any group and the neighbor IP address matches the source IP address of the existing dynamic neighbor, the dynamic neighbor session is taken down and a new session is established using the configured parameters of the static neighbor

Static sessions always take precedence regardless of any longest-prefix match with a dynamic neighbor prefix entry.

The number of dynamic BGP peers can be limited at the BGP global and BGP group levels using the dynamic-neighbor-limit command, which limits the number of dynamic sessions allowed by the router and the group, respectively. If an incoming connection for a new dynamic session exceeds the BGP global or BGP group limit, the connection attempt is rejected and a notification message is issued.

The following example displays the dynamic-neighbor command usage:

Example:
config>router# bgp
config>router>bgp# group ‟dynamic”
config>router>bgp>group# peer-as 100
config>router>bgp>group# dynamic-neighbor 
config>router>bgp>group>dynamic-neighbor$ prefix 10.100.0.0/16 
config>router>bgp>group>dynamic-neighbor# exit
config>router>bgp>group# dynamic-neighbor-limit 75 
config>router>bgp>group# exit

The following example displays a dynamic neighbor configuration:

ALU-B>config>router>bgp# info
---------------------------------------------

...snip...

    group "dynamic"
        peer-as 100
        dynamic-neighbor
            prefix 10.100.0.0/16
        exit
        dynamic-neighbor-limit 75
    exit

...snip...
---------------------------------------------
ALU-B>config>router>bgp#

BGP Configuration Management Tasks

This section discusses the following BGP configuration management tasks:

Modifying an AS Number

You can modify an AS number on a 7705 SAR but the new AS number will not be used until the BGP instance is restarted either by administratively disabling or enabling the BGP instance, or by rebooting the system with the new configuration.

Since the AS number is defined in the config>router context, not in the BGP configuration context, the BGP instance is not aware of the change. Re-examine the plan detailing the autonomous systems, the 7705 SARs belonging to each group, group names, and peering connections.

Note: Changing an AS number on a 7705 SAR could cause configuration inconsistencies if associated peer-as values are not also modified as required. At the group and neighbor levels, BGP will re-establish the peer relationships with all peers in the group with the new AS number.

Use the following CLI syntax to change an autonomous system number:

CLI Syntax:
config>router# autonomous-system as-number
config>router# bgp
    group name
        neighbor ip-addr
            peer-as as-number
Example:
config>router# autonomous-system 400
config>router# bgp
config>router>bgp# group headquarters1
config>router>bgp>group# neighbor 10.10.10.103
config>router>bgp>group# peer-as 400
config>router>bgp>group# exit

Modifying the BGP Router ID

Changing the router ID number in the BGP context causes the new value to overwrite the router ID configured on the router level, system interface level, or the value inherited from the MAC address.

Note: Changing the router ID on a router could cause configuration inconsistencies if associated values are not also modified.

When configuring a new router ID, protocols are not automatically restarted with the new router ID. The next time a protocol is initialized or reinitialized, the new router ID is used.

To force the new router ID for BGP, issue the shutdown and no shutdown commands or restart the router.

Example:
config>router>bgp# router-id 10.0.0.104
config>router>bgp# shutdown
config>router>bgp# router-id 10.0.0.123
config>router>bgp# no shutdown

This example displays the BGP configuration with the BGP router ID specified:

ALU-B>config>router>bgp# info detail
----------------------------------------------
    no shutdown
    no description
    no always-compare-med
    ibgp-multipath load-balance
. . .
    router-id 10.0.0.123
----------------------------------------------
ALU-B>config>router>bgp#

Modifying the Router-Level Router ID

Changing the router ID number in the config>router context causes the new value to overwrite the router ID configured on the protocol level, system interface level, or the value inherited from the MAC address.

Note: Changing the router ID on a router could cause configuration inconsistencies if associated values are not also modified.

When configuring a new router ID, protocols are not automatically restarted with the new router ID. The next time a protocol is initialized or reinitialized, the new router ID is used. An interim period of time can occur when different protocols use different router IDs. To force the new router ID, issue the shutdown and no shutdown commands for each protocol that uses the router ID or restart the entire router.

Use the following CLI syntax to change a router ID:

CLI Syntax:
config>router# router-id ip-address
Example:
config>router# router-id 10.10.10.104
config>router# no shutdown
config>router>bgp# shutdown
config>router>bgp# no shutdown

The following example displays the router ID configuration:

ALU-A>config>router# info
#------------------------------------------
# IP Configuration
#------------------------------------------
    interface "system"
        address 10.10.10.104/8
    exit
    interface "to-103"
        address 10.0.0.104/8
        port 1/1/1
    exit
    autonomous-system 100
    router-id 10.10.10.104
#------------------------------------------
ALU-B>config>router#

Deleting a Neighbor

In order to delete a neighbor, you must shut down the neighbor before issuing the no neighbor ip-addr command.

Use the following CLI syntax to delete a neighbor:

CLI Syntax:
config>router# bgp
    group name
        neighbor ip-address
             shutdown
             exit
        no neighbor ip-address
Example:
config>router# bgp
config>router>bgp# group headquarters1
config>router>bgp>group# neighbor 10.0.0.103
config>router>bgp>group>neighbor# shutdown
config>router>bgp>group>neighbor# exit
config>router>bgp>group# no neighbor 10.0.0.103

The following example displays the ‟headquarters1” configuration with the neighbor 10.0.0.103 removed.

ALU-B>config>router>bgp# info
----------------------------------------------
    group "headquarters1"
        description ‟HQ execs”
            local-address 10.0.0.104
            neighbor 10.0.0.5
                passive
                peer-as 300
            exit
        exit
----------------------------------------------
ALU-B>config>router>bgp#

Deleting Groups

In order to delete a group, the neighbor configurations must be shut down first. After each neighbor is shut down, you must shut down the group before issuing the no group name command.

Use the following CLI syntax to shut down a peer and neighbor and then delete a group:

CLI Syntax:
config>router# bgp
    group name
        neighbor ip-address
              shutdown
              exit
        neighbor ip-address
              shutdown
              exit
        shutdown
        exit
     no group name
Example:
config>router# bgp
config>router>bgp# group headquarters1
config>router>bgp>group# neighbor 10.0.0.105
config>router>bgp>group>neighbor# shutdown
config>router>bgp>group>neighbor# exit
config>router>bgp>group# neighbor 10.0.0.103
config>router>bgp>group>neighbor# shutdown
config>router>bgp>group>neighbor# exit
config>router>bgp>group# shutdown
config>router>bgp>group# exit
config>router>bgp# no group headquarters1

If you try to delete the group without shutting it down first, the following message appears:

ALU-B>config>router>bgp# no group headquarters1
MINOR: CLI BGP Peer Group should be shutdown before deleted. BGP Peer Group not deleted.

Editing BGP Parameters

You can change existing BGP parameters in the CLI. The changes are applied immediately.

CLI Syntax:
config>router# bgp
    group name
    . . .
        neighbor ip-address
    . . .
Example:
config>router# bgp

See BGP Components for a complete list of BGP parameters.

BGP Command Reference

Command Hierarchies

Configuration Commands

Global BGP Commands 
config 
    - router [router-name]
        - [no] bgp
            - [no] add-paths 
                - ipv4 send send-limit receive [none]
                - ipv4 send send-limit
                - no ipv4
                - ipv6 send send-limit receive [none]
                - ipv6 send send-limit 
                - no ipv6
                - label-ipv4 send send-limit receive [none]
                - label-ipv4 send send-limit
                - no label-ipv4
                - label-ipv6 send send-limit receive [none]
                - label-ipv6 send send-limit
                - no label-ipv6
                - vpn-ipv4 send send-limit receive [none]
                - vpn-ipv4 send send-limit
                - no vpn-ipv4
                - vpn-ipv6 send send-limit receive [none]
                - vpn-ipv6 send send-limit
                - no vpn-ipv6
            - [no] advertise-inactive 
            - [no] aggregator-id-zero
            - auth-keychain name
            - no auth-keychain 
            - authentication-key {authentication-key | hash-key} [hash | hash2]
            - no authentication-key 
            - [no] backup-path [ipv4] [label-ipv4] [ipv6] [label-ipv6]
            - best-path-selection
                - always-compare-med [zero | infinity]
                - always-compare-med strict-as [zero | infinity]
                - no always-compare-med
                - as-path-ignore [ipv4] [ipv6] [vpn-ipv4] [vpn-ipv6] [mvpn-ipv4]  [label-ipv4]  [label-ipv6] 
                - no as-path-ignore 
            - [no] bfd-enable
            - cluster cluster-id
            - no cluster
            - connect-retry seconds
            - no connect-retry 
            - [no] damping 
            - def-recv-evpn-encap encap-type 
            - no def-recv-evpn-encap 
            - description description-string
            - no description
            - [no] disable-client-reflect
            - disable-communities [standard] [extended]
            - [no] disable-communities
            - [no] disable-fast-external-failover
            - dynamic-neighbor-limit peers
            - no dynamic-neighbor-limit
            - [no] enable-peer-tracking 
            - [no] enable-rr-vpn-forwarding 
            - export policy-name [policy-name…(up to 5 max)]
            - no export [policy-name] 
            - family [ipv4] [vpn-ipv4] [ipv6] [vpn-ipv6] [mvpn-ipv4] [route-target] [evpn] [label-ipv4] [label-ipv6] [bgp-ls] 
            - no family
            - [no] graceful-restart
                - stale-routes-time time
                - no stale-routes-time
            - [no] group name
                - [no] add-paths 
            - hold-time seconds [min seconds2] 
            - no hold-time
            - [no] ibgp-multipath
            - import policy-name [policy-name…(up to 5 max)]
            - no import [policy-name]
            - keepalive seconds
            - no keepalive
            - label-preference value
            - no label-preference
            - [no] link-state-export-enable 
            - [no] link-state-import-enable
            - local-as as-number [private]
            - no local-as
            - local-preference local-preference
            - no local-preference
            - loop-detect {drop-peer | discard-route | ignore-loop | off}
            - no loop-detect
            - med-out {number | igp-cost}
            - no med-out 
            - min-route-advertisement seconds
            - no min-route-advertisement
            - multihop ttl-value 
            - no multihop
            - multipath integer 
            - no multipath
            - [no] mvpn-vrf-import-subtype-new 
            - next-hop-resolution
                - label-route-transport-tunnel
                        - family family 
                            - resolution {any | filter | disabled}
                            - resolution-filter
                                - [no] ldp
                                - [no] rsvp
                                - [no] sr-isis
                                - [no] sr-ospf
                                - [no] sr-te
                - policy policy-name
                - no policy
            - [no] outbound-route-filtering
                - [no] extended-community
                    - [no] accept-orf
                    - send-orf [comm-id...(up to 32 max)]
                    - no send-orf comm-id
            - peer-tracking-policy policy-name
            - no peer-tracking-policy
            - preference preference
            - no preference
            - rapid-update [mvpn-ipv4] [evpn] 
            - no rapid-update
            - [no] rapid-withdrawal
            - [no] remove-private [limited] 
            - rib-management
                - ipv4
                    - route-table-import policy-name
                    - no route-table-import
                - ipv6
                    - route-table-import policy-name
                    - no route-table-import
                - label-ipv4
                    - route-table-import policy-name
                    - no route-table-import
                - label-ipv6
                    - route-table-import policy-name
                    - no route-table-import
            - route-target-list comm-id [comm-id...(up to 15 max)]
            - no route-target-list [comm-id]
            - router-id ip-address
            - no router-id 
            - [no] shutdown 
            - [no] split-horizon
            - [no] vpn-apply-export
            - [no] vpn-apply-import
Group BGP Commands 
config
    - router [router-name]
        - [no] bgp
            - [no] group name
                - [no] add-paths 
                    - ipv4 send send-limit receive [none]
                    - ipv4 send send-limit
                    - no ipv4
                    - ipv6 send send-limit receive [none]
                    - ipv6 send send-limit 
                    - no ipv6
                    - label-ipv4 send send-limit receive [none]
                    - label-ipv4 send send-limit 
                    - no label-ipv4
                    - label-ipv6 send send-limit  receive [none]
                    - label-ipv6 send send-limit
                    - no label ipv6
                    - vpn-ipv4 send send-limit receive [none]
                    - vpn-ipv4 send send-limit
                    - no vpn-ipv4
                    - vpn-ipv6 send send-limit receive [none]
                    - vpn-ipv6 send send-limit
                    - no vpn-ipv6
                - [no] advertise-inactive 
                - [no] aggregator-id-zero
                - [no] aigp
                - auth-keychain name
                - no auth-keychain 
                - authentication-key {authentication-key | hash-key} [hash | hash2]
                - no authentication-key 
                - [no] bfd-enable
                - cluster cluster-id
                - no cluster
                - connect-retry seconds
                - no connect-retry
                - [no] damping 
                - def-recv-evpn-encap encap-type 
                - no def-recv-evpn-encap 
                - [no] default-route-target 
                - description description-string
                - no description
                - [no] disable-client-reflect
                - disable-communities [standard] [extended]
                - no disable-communities
                - [no] disable-fast-external-failover
                - dynamic-neighbor
                    - [no] prefix ip-prefix/ip-prefix-length
                - dynamic-neighbor-limit peers
                - no dynamic-neighbor-limit
                - [no] enable-peer-tracking 
                - export policy-name [policy-name…(up to 5 max)]
                - no export [policy-name] 
                - family [ipv4] [vpn-ipv4] [ipv6] [vpn-ipv6] [mvpn-ipv4] [route-target] [evpn] [label-ipv4] [label-ipv6] [bgp-ls]
                - no family
                - [no] graceful-restart
                    - stale-routes-time time
                    - no stale-routes-time
                - hold-time seconds [min seconds2] 
                - no hold-time
                - import policy-name [policy-name…(up to 5 max)]
                - no import [policy-name]
                - keepalive seconds
                - no keepalive
                - label-preference value
                - no label-preference
                - local-address ip-address
                - no local-address
                - local-as as-number [private]
                - no local-as
                - local-preference local-preference
                - no local-preference
                - loop-detect {drop-peer | discard-route | ignore-loop | off}
                - no loop-detect
                - med-out {number | igp-cost}
                - no med-out 
                - min-route-advertisement seconds
                - no min-route-advertisement
                - multihop ttl-value 
                - no multihop
                - [no] neighbor ip-address 
                - [no] next-hop-self
                - [no] outbound-route-filtering
                - [no] extended-community
                    - [no] accept-orf
                    - send-orf [comm-id...(up to 32 max)]
                    - no send-orf comm-id
                - [no] passive
                - peer-as as-number
                - no peer-as
                - preference preference
                - no preference
                - prefix-limit family limit [threshold percentage] [idle-timeout {minutes | forever} | log-only] [post-import]
                - no prefix-limit family
                - [no] remove-private [limited]
                - [no] shutdown
                - [no] split-horizon
                - ttl-security min-ttl-value
                - no ttl-security
                - [no] vpn-apply-export
                - [no] vpn-apply-import
Neighbor BGP Commands 
config 
    - router [router-name]
        - [no] bgp
            - [no] group name
                - [no] neighbor ip-address
                    - [no] add-paths 
                        - ipv4 send send-limit receive [none]
                        - ipv4 send send-limit
                        - no ipv4
                        - ipv6 send send-limit receive [none]
                        - ipv6 send send-limit 
                        - no ipv6
                        - label-ipv4 send send-limit receive [none]
                        - label-ipv4 send send-limit 
                        - no label-ipv4
                        - label-ipv6 send send-limit receive [none]
                        - label-ipv6 send send-limit
                        - no label-ipv6
                        - vpn-ipv4 send send-limit receive [none]
                        - vpn-ipv4 send send-limit
                        - no vpn-ipv4
                        - vpn-ipv6 send send-limit receive [none]
                        - vpn-ipv6 send send-limit
                        - no vpn-ipv6
                    - [no] advertise-inactive 
                    - [no] aggregator-id-zero
                    - [no] aigp
                    - auth-keychain name
                    - no auth-keychain 
                    - authentication-key {authentication-key | hash-key} [hash | hash2]
                    - no authentication-key 
                    - [no] bfd-enable
                    - cluster cluster-id
                    - no cluster
                    - connect-retry seconds
                    - no connect-retry
                    - [no] damping 
                    - def-recv-evpn-encap encap-type 
                    - no def-recv-evpn-encap 
                    - [no] default-route-target 
                    - description description-string
                    - no description
                    - [no] disable-client-reflect
                    - disable-communities [standard] [extended]
                    - no disable-communities
                    - [no] disable-fast-external-failover
                    - [no] enable-peer-tracking 
                    - export policy-name [policy-name…(up to 5 max)]
                    - no export [policy-name] 
                    - family [ipv4] [vpn-ipv4] [ipv6] [vpn-ipv6] [mvpn-ipv4] [route-target] [evpn] [label-ipv4] [label-ipv6] [bgp-ls]
                    - no family
                    - [no] graceful-restart
                        - stale-routes-time time
                        - no stale-routes-time
                    - hold-time seconds  [min seconds2] 
                    - no hold-time
                    - import policy-name [policy-name…(up to 5 max)]
                    - no import [policy-name] 
                    - keepalive seconds
                    - no keepalive
                    - label-preference value
                    - no label-preference
                    - local-address ip-address
                    - no local-address
                    - local-as as-number [private]
                    - no local-as
                    - local-preference local-preference
                    - no local-preference
                    - loop-detect {drop-peer | discard-route | ignore-loop | off}
                    - no loop-detect
                    - med-out {number | igp-cost}
                    - no med-out 
                    - min-route-advertisement seconds
                    - no min-route-advertisement
                    - multihop ttl-value 
                    - no multihop
                    - [no] next-hop-self
                    - [no] outbound-route-filtering
                        - [no] extended-community
                            - [no] accept-orf
                            - send-orf [comm-id...(up to 32 max)]
                            - no send-orf comm-id
                    - [no] passive
                    - peer-as as-number
                    - no peer-as
                    - preference preference
                    - no preference
                    - prefix-limit family limit [threshold percentage] [idle-timeout {minutes | forever} | log-only] [post-import]
                    - no prefix-limit family
                    - [no] remove-private [limited]
                    - [no] shutdown
                    - [no] split-horizon
                    - ttl-security min-ttl-value
                    - no ttl-security
                    - [no] vpn-apply-export
                    - [no] vpn-apply-import

Show Commands

show
    - router [router-instance]
    - router service-name service-name 
        - bgp
            - auth-keychain [keychain]
            - damping [ip-prefix[/ip-prefix-length]] [damp-type] [detail] [ipv4]
            - damping [ip-prefix[/ip-prefix-length]] [damp-type] [detail] ipv6
            - damping [ip-prefix[/ip-prefix-length]] [damp-type] [detail] label-ipv4
            - damping [ip-prefix[/ip-prefix-length]] [damp-type] [detail] label-ipv6
            - damping [ip-prefix[/ip-prefix-length]] [damp-type] [detail] vpn-ipv4
            - damping [ip-prefix[/ip-prefix-length]] [damp-type] [detail] vpn-ipv6
            - damping [ip-prefix[/ip-prefix-length]] [damp-type] [detail] mvpn-ipv4
            - group [name] [detail]
            - inter-as-label
            - neighbor [ip-address [detail]]
            - neighbor [as-number [detail]]
            - neighbor [ip-address [family [type mvpn-type]] filter1 [brief]]]
            - neighbor [ip-address [[family] filter2]]
            - neighbor [as-number [[family] filter2]]
            - neighbor ip-address orf [filter3]
            - neighbor ip-address graceful-restart
            - neighbor [dynamic]
            - next-hop [family] [ip-address] [detail]
            - paths 
            - routes [ip-prefix/mask | ip-address]
            - routes aspath-regex reg-exp {detail | longer}
            - routes aspath-regex reg-exp 
            - routes aspath-regex reg-exp hunt
            - routes bgp-ls [hunt] [node | link | ipv4-prefix [ipv4-prefix/mask-len]]
            - routes brief
            - routes community comm-id {detail |longer}
            - routes community comm-id
            - routes community comm-id hunt
            - routes detail
            - routes hunt [brief]
            - routes ipv4 [aspath-regex reg-exp] [community comm-id] [brief] [all]
            - routes ipv4 [aspath-regex reg-exp] hunt [community comm-id] brief] [all]
            - routes ipv4 [detail |longer] [aspath-regex reg-exp] [community comm-id] [all]
            - routes ipv6 [aspath-regex reg-exp] [community comm-id] [brief] [all]
            - routes ipv6 [aspath-regex reg-exp] hunt [community comm-id] [brief] [all]
            - routes ipv6 [detail |longer] [aspath-regex reg-exp] [community comm-id] [all]
            - routes label-ipv4 [aspath-regex reg-exp] [community comm-id] [brief] [all]
            - routes label-ipv4 [aspath-regex reg-exp] hunt [community comm-id] [brief] [all]
            - routes label-ipv4 [detail | longer] [aspath-regex reg-exp] [community comm-id] [all]
            - routes label-ipv6 [aspath-regex reg-exp] [community comm-id] [brief] [all]
            - routes label-ipv6 [aspath-regex reg-exp] hunt [community comm-id] [brief] [all]
            - routes label-ipv6 [detail | longer] [aspath-regex reg-exp] [community comm-id] [all]
            - routes longer
            - routes mvpn-ipv4 [aspath-regex reg-exp] [community comm-id] [rd rd] [brief] [type mvpn-type] [originator-ip ip-address] [source-ip ipv4 address |pv6 address] [group-ip ipv4 address | ipv6 address] [source-as as-number]
            - routes mvpn-ipv4 [aspath-regex reg-exp] hunt [community comm-id] [rd rd] [brief] [type mvpn-type] [originator-ip ip-address] [source-ip ipv4 address |ipv6 address] [group-ip ipv4 address | ipv6 address] [source-as as-number]
            - routes mvpn-ipv4 [detail |longer] [aspath-regex reg-exp] [community comm-id] [rd rd] [type mvpn-type] [originator-ip ip-address] [source-ip ipv4 address |ipv6 address] [group-ip ipv4 address | ipv6 address] [source-as as-number]
            - routes route-target [source-as as-number] [brief] [aspath-regex reg-exp] [community comm-id]
            - routes route-target [rtc-prefix rtc-prefix] [hunt] [brief] [aspath-regex reg-exp] [community comm-id]
            - routes route-target [rtc-prefix rtc-prefix [aspath-regex reg-exp] [community comm-id]
            - routes route-target [rtc-prefix rtc-prefix] [detail | longer] [aspath-regex reg-exp] [community comm-id]
            - routes vpn-ipv4 [aspath-regex reg-exp] [community comm-id] [rd rd] [brief]
            - routes vpn-ipv4 [aspath-regex reg-exp] hunt [community comm-id] [rd rd] [brief]
            - routes vpn-ipv4 [detail |longer] [aspath-regex reg-exp] [community comm-id] [rd rd]
            - routes vpn-ipv6 [aspath-regex reg-exp] [community comm-id] [rd rd] [brief]
            - routes vpn-ipv6 [aspath-regex reg-exp] hunt [community comm-id] [rd rd] [brief]
            - routes vpn-ipv6 [detail |longer] [aspath-regex reg-exp] [community comm-id] [rd rd]
            - summary [all]
            - summary [family family] [neighbor ip-address]

Clear Commands

clear
    - router
        - bgp
            - flap-statistics [{ip-prefix/mask [neighbor ip-address] | group group-name | regex reg-exp | policy policy-name}]
            - neighbor {ip-address | as as-number | external | all} [soft | soft-inbound]
            - neighbor {ip-address | as as-number | external | all} statistics
            - neighbor ip-address end-of-rib
            - protocol

Debug Commands

debug
    - router
        - bgp
            - events [neighbor ip-address | group name]
            - no events 
            - graceful-restart [neighbor ip-address | group name]
            - no graceful-restart 
            - keepalive [neighbor ip-address | group name]
            - no keepalive 
            - notification [neighbor ip-address | group name]
            - no notification 
            - open [neighbor ip-address | group name]
            - no open 
            - [no] outbound-route-filtering 
            - packets [neighbor ip-address | group name]
            - no packets 
            - route-refresh [neighbor ip-address | group name]
            - no route-refresh 
            - rtm [neighbor ip-address | group name]
            - no rtm 
            - socket [neighbor ip-address | group name]
            - no socket 
            - timers [neighbor ip-address | group name]
            - no timers 
            - update [neighbor ip-address | group name]
            - no update

Command Descriptions

Configuration Commands

Configuration Commands
bgp
Syntax

[no] bgp

Context

config>router

Description

This command creates the BGP protocol instance and BGP configuration context. BGP is administratively enabled upon creation.

The no form of the command deletes the BGP protocol instance and removes all configuration parameters for the BGP instance. BGP must be shut down before deleting the BGP instance. An error occurs if BGP is not shut down first.

Default

no bgp

add-paths
Syntax

[no] add-paths

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command creates the add-paths configuration context and enables add-paths to be configured for one or more families on a BGP instance, BGP group, or BGP neighbor. The BGP add-paths capability allows the router to send and/or receive multiple paths per prefix to/from a peer. The add-paths command without additional parameters is equivalent to removing add-paths support for all address families, which causes sessions that previously negotiated the add-paths capability for one or more address families to go down and come back up without the add-paths capability.

The no form of the command removes add-paths from the configuration of BGP, BGP group, or BGP neighbor, causing sessions established using add-paths to go down and come back up without the add-paths capability.

Default

no add-paths

ipv4
Syntax

ipv4 send send-limit receive [none]

ipv4 send send-limit

no ipv4

Context

config>router>bgp>add-paths

config>router>bgp>group>add-paths

config>router>bgp>group>neighbor>add-paths

Description

This command is used to configure the add-paths capability for IPv4 routes (including labeled IPv4 routes on BGP route tunnels). By default, add-paths is not enabled for IPv4 routes.

The maximum number of paths to send per IPv4 prefix is the configured send limit, which is a mandatory parameter. The capability to receive multiple paths per prefix from a peer is configurable using the receive keyword, which is optional. If the receive keyword is not included in the command, the receive capability is enabled by default. Entering the command without optional parameters enables the ability to both send and receive multiple paths per IPv4 prefix with each peer, and configures the router to send the two best paths per prefix to each peer using the default Add-N, N=2 path selection algorithm.

The BGP advertise-inactive, add-paths, and export policy commands can be configured such that active, non-BGP routes are advertised. For more information, see Advertise-Inactive, Add-Paths, and Export Policy Interaction.

The no form of the command removes add-path support for IPv4 routes, causing sessions established using add-paths for IPv4 to go down and come back up without the add-paths capability.

Default

no ipv4

Parameters
send-limit

the maximum number of paths per IPv4 prefix that are allowed to be advertised to add-path peers. The actual number of advertised routes may be less depending on the next-hop diversity requirement, other configuration options, route policies, and/or route advertisement rules. If the value is none, the router does not negotiate the send capability with respect to IPv4 AFI/SAFI.

Values

1 to 16, or none

receive

configures the router to negotiate the add-paths receive capability for IPv4 routes with its peers

none

the router does not negotiate the add-paths receive capability for IPv4 routes with its peers

ipv6
Syntax

ipv6 send send-limit receive [none]

ipv6 send send-limit

no ipv6

Context

config>router>bgp>add-paths

config>router>bgp>group>add-paths

config>router>bgp>group>neighbor>add-paths

Description

This command is used to configure the add-paths capability for unlabeled IPv6 unicast routes. By default, add-paths is not enabled for unlabeled IPv6 unicast routes.

The maximum number of unlabeled unicast paths to send per IPv6 prefix is the configured send limit, which is a mandatory parameter. The capability to receive multiple unlabeled IPv6 unicast paths per prefix from a peer is configurable using the receive keyword, which is optional. If the receive keyword is not included in the command, the receive capability is enabled by default.

The no form of the command removes add-path support for unlabeled IPv6 unicast routes, causing sessions established using add-paths for unlabeled IPv6 unicast to go down and come back up without the add-paths capability.

Default

no ipv6

Parameters
send-limit

the maximum number of paths per unlabeled IPv6 unicast prefix that are allowed to be advertised to add-path peers. (The actual number of advertised routes may be less.) If the value is none, the router does not negotiate the send capability with respect to IPv6 AFI/SAFI.

Values

1 to 16, or none

receive

the router negotiates to receive multiple unlabeled unicast routes per IPv6 prefix

none

the router does not negotiate to receive multiple unlabeled unicast routes per IPv6 prefix

label-ipv4
Syntax

label-ipv4 send send-limit receive [none]

label-ipv4 send send-limit

no label-ipv4

Context

config>router>bgp>add-paths

config>router>bgp>group>add-paths

config>router>bgp>group>neighbor>add-paths

Description

This command is used to configure the add-paths capability for labeled unicast IPv4 routes. By default, add-paths is not enabled for labeled unicast IPv4 routes.

The maximum number of labeled unicast paths per IPv4 prefix to send is the configured send-limit, which is a mandatory parameter. The capability to receive multiple labeled unicast paths per prefix from a peer is configurable using the receive keyword, which is optional. If the receive keyword is not included in the command, receive capability is enabled by default.

The no form of the command disables add-paths support for labeled unicast IPv4 routes, causing sessions established using add-paths for labeled unicast IPv4 to go down and come back up without the add-paths capability.

Default

no label-ipv4

Parameters
send-limit

the maximum number of paths per labeled unicast IPv4 prefix that are allowed to be advertised to add-paths peers. The actual number of advertised routes may be less. If the value is none, the router does not negotiate the send capability with respect to label-IPv4 AFI/SAFI.

Values

1 to 16, none

receive

configures the router to negotiate to receive multiple labeled unicast routes per IPv4 prefix

none

the router does not negotiate to receive multiple labeled unicast routes per IPv4 prefix

label-ipv6
Syntax

label-ipv6 send send-limit receive [none]

label-ipv6 send send-limit

no label-ipv6

Context

config>router>bgp>add-paths

config>router>bgp>group>add-paths

config>router>bgp>group>neighbor>add-paths

Description

This command is used to configure the add-paths capability for labeled unicast IPv6 routes. By default, add-paths is not enabled for labeled unicast IPv6 routes.

The maximum number of labeled unicast paths per IPv6 prefix to send is the configured send-limit, which is a mandatory parameter. The capability to receive multiple labeled unicast paths per prefix from a peer is configurable using the receive keyword, which is optional. If the receive keyword is not included in the command, receive capability is enabled by default.

The no form of the command disables add-paths support for labeled unicast IPv6 routes, causing sessions established using add-paths for labeled unicast IPv6 to go down and come back up without the add-paths capability.

Default

no label-ipv6

Parameters
send-limit

the maximum number of paths per labeled unicast IPv6 prefix that are allowed to be advertised to add-paths peers. The actual number of advertised routes may be less. If the value is none, the router does not negotiate the send capability with respect to label-IPv6 AFI/SAFI.

Values

1 to 16, none

receive

configures the router to negotiate to receive multiple labeled unicast routes per IPv6 prefix

none

the router does not negotiate to receive multiple labeled unicast routes per IPv6 prefix

vpn-ipv4
Syntax

vpn-ipv4 send send-limit receive [none]

vpn-ipv4 send send-limit

no vpn-ipv4

Context

config>router>bgp>add-paths

config>router>bgp>group>add-paths

config>router>bgp>group>neighbor>add-paths

Description

This command is used to configure the add-paths capability for VPN-IPv4 routes. By default, add-paths is not enabled for VPN-IPv4 routes.

The maximum number of paths to send per VPN-IPv4 prefix is the configured send limit, which is a mandatory parameter. The capability to receive multiple paths per prefix from a peer is configurable using the receive keyword, which is optional. If the receive keyword is not included in the command, the receive capability is enabled by default.

The BGP advertise-inactive, add-paths, and export policy commands can be configured such that active, non-BGP routes are advertised. For more information, see Advertise-Inactive, Add-Paths, and Export Policy Interaction.

The no form of the command removes add-path support for VPN-IPv4 routes, causing sessions established using add-paths for VPN-IPv4 to go down and come back up without the add-paths capability.

Default

no vpn-ipv4

Parameters
send-limit

the maximum number of paths per VPN-IPv4 prefix that are allowed to be advertised to add-path peers. The actual number of advertised routes may be less depending on the next-hop diversity requirement, other configuration options, route policies, and/or route advertisement rules. If the value is none, the router does not negotiate the send capability with respect to VPN-IPv4 AFI/SAFI.

Values

1 to 16, or none

receive

configures the router to negotiate the add-paths receive capability for VPN-IPv4 routes with its peers

none

the router does not negotiate the add-paths receive capability for VPN-IPv4 routes with its peers

vpn-ipv6
Syntax

vpn-ipv6 send send-limit receive [none]

vpn-ipv6 send send-limit

no vpn-ipv6

Context

config>router>bgp>add-paths

config>router>bgp>group>add-paths

config>router>bgp>group>neighbor>add-paths

Description

This command is used to configure the add-paths capability for VPN-IPv6 routes. By default, add-paths is not enabled for VPN-IPv6 routes.

The maximum number of paths to send per VPN-IPv6 prefix is the configured send limit, which is a mandatory parameter. The capability to receive multiple paths per prefix from a peer is configurable using the receive keyword, which is optional. If the receive keyword is not included in the command, the receive capability is enabled by default.

The BGP advertise-inactive, add-paths, and export policy commands can be configured such that active, non-BGP routes are advertised. For more information, see Advertise-Inactive, Add-Paths, and Export Policy Interaction.

The no form of the command removes add-path support for VPN-IPv6 routes, causing sessions established using add-paths for VPN-IPv6 to go down and come back up without the add-paths capability.

Default

no vpn-ipv6

Parameters
send-limit

the maximum number of paths per VPN-IPv6 prefix that are allowed to be advertised to add-path peers. The actual number of advertised routes may be less depending on the next-hop diversity requirement, other configuration options, route policies, and/or route advertisement rules. If the value is none, the router does not negotiate the send capability with respect to VPN-IPv6 AFI/SAFI.

Values

1 to 16, or none

receive

configures the router to negotiate the add-paths receive capability for VPN-IPv6 routes with its peers

none

the router does not negotiate the add-paths receive capability for VPN-IPv6 routes with its peers

advertise-inactive
Syntax

[no] advertise-inactive

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command enables the advertising of inactive BGP routes to other BGP peers. By default, BGP only advertises BGP routes to other BGP peers if a given BGP route is chosen by the route table manager as the most preferred route within the system and is active in the forwarding plane. This command allows system administrators to advertise a BGP route even though it is not the most preferred route within the system for a given destination.

The BGP advertise-inactive, add-paths, and export policy commands can be configured such that active, non-BGP routes are advertised. For more information, see Advertise-Inactive, Add-Paths, and Export Policy Interaction.

The no form of the command disables the advertising of inactive BGP routers to other BGP peers.

Default

no advertise-inactive

aggregator-id-zero
Syntax

[no] aggregator-id-zero

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command is used to set the router ID in the BGP aggregator path attribute to 0 when BGP aggregates routes. This prevents different routers within an AS from creating aggregate routes that contain different AS paths.

When BGP is aggregating routes, it adds the aggregator path attribute to the BGP Update messages. By default, BGP adds the AS number and router ID to the aggregator path attribute.

When this command is enabled, BGP adds only the router ID (set to 0) to the aggregator path attribute. This command is used at the group level to revert to the value defined under the global level, and this command is used at the neighbor level to revert to the value defined under the group level.

The no form of the command used at the global level reverts to the default, where BGP adds the AS number and router ID to the aggregator path attribute.

The no form of the command used at the group level reverts to the value defined at the global level.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

no aggregator-id-zero

aigp
Syntax

[no] aigp

Context

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command enables or disables accumulated IGP (AIGP) metric path attribute support with one or more BGP peers. BGP path selection among routes with an associated AIGP metric is based on the end-to-end IGP metrics of the different BGP paths, even when these BGP paths span more than one AS and IGP instance.

If AIGP is disabled, the AIGP attribute is removed from advertised routes, if present, and is ignored in received routes.

Default

no aigp

auth-keychain
Syntax

auth-keychain name

no auth-keychain

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command associates an authentication keychain with the BGP protocol. The keychain is a collection of keys used to authenticate BGP messages from remote neighbors. The keychain allows the rollover of authentication keys during the lifetime of a session and also supports stronger authentication algorithms than clear text and MD5.

The keychain must already be defined in the config>system>security>keychain context.

Either the authentication-key command or the auth-keychain command can be used by BGP, but both cannot be supported at the same time. If both commands are configured, the auth-keychain configuration will be applied and the authentication-key command will be ignored.

By default, authentication is not enabled.

Default

no auth-keychain

Parameters
name

the name of an existing keychain, up to 32 characters

authentication-key
Syntax

authentication-key {authentication-key | hash-key} [hash | hash2]

no authentication-key

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures the BGP authentication key.

Authentication is performed between neighboring routers before setting up the BGP session by verifying the password. Authentication is performed using the MD5 message-based digest.

The authentication key can be any combination of ASCII characters up to 255 characters long.

The TCP MD5 key information used to securely communicate with a BGP peer is retained even after the connection has closed, allowing connectionless RST packets to be sent with the proper authentication data.

Either the authentication-key command or the auth-keychain command can be used by BGP, but both cannot be supported at the same time. If both commands are configured, the auth-keychain configuration will be applied and the authentication-key command will be ignored.

The no form of the command reverts to the default value.

Default

MD5 authentication is disabled by default

Parameters
authentication-key

the authentication key. The key can be any combination of ASCII characters up to 255 characters in length (unencrypted). If spaces are used in the string, the entire string must be enclosed in quotation marks (‟ ”).

hash-key

the hash key. The key can be any combination of ASCII characters up to 342 characters in length (encrypted). If spaces are used in the string, the entire string must be enclosed in quotation marks (‟ ”). This is useful when a user must configure the parameter, but for security purposes, the actual unencrypted key value is not provided.

hash

specifies that the key is entered in an encrypted form. If the hash parameter is not used, the key is assumed to be in a non-encrypted, clear text form. For security, all keys are stored in encrypted form in the configuration file with the hash parameter specified.

hash2

specifies that the key is entered in a more complex encrypted form. If the hash2 parameter is not used, the less encrypted hash form is assumed.

backup-path
Syntax

[no] backup-path [ipv4] [label-ipv4] [ipv6] [label-ipv6]

Context

config>router>bgp

Description

This command enables BGP Fast Reroute (FRR) with Prefix-Independent Convergence (PIC), allowing for the creation of a backup path for IPv4, label IPv4, or IPv6 learned prefixes belonging to the router. Multiple paths must be received for a prefix in order to take advantage of this feature.

When a prefix has a backup path, and its primary paths fail, the affected traffic is rapidly diverted to the backup path without waiting for control plane reconvergence to occur. The time to reroute the traffic is independent of the number of prefixes sharing the primary or backup paths.

The no form of the command disables BGP FRR with PIC.

Default

no backup-path

Parameters
ipv4

enables a backup path for IPv4 BGP learned prefixes

label-ipv4

enables a backup path for labeled IPv4 BGP learned prefixes

ipv6

enables a backup path for IPv6 BGP learned prefixes

label-ipv6

enables a backup path for labeled IPv6 BGP learned prefixes

best-path-selection
Syntax

best-path-selection

Context

config>router>bgp

Description

This command enables path selection configuration.

always-compare-med
Syntax

always-compare-med [zero | infinity]

always-compare-med strict-as [zero | infinity]

no always-compare-med

Context

config>router>bgp>path-selection

Description

This command specifies how the Multi-Exit Discriminator (MED) path attribute is used in the BGP route selection process.

If this command is used without the strict-as option, the MEDs of two paths are always compared even if the paths have a different neighbor AS.

If the strict-as option is used, the MEDs of two paths are compared only if they come from the same neighboring AS.

The zero and infinity options specify how to treat paths that do not have a MED attribute; for example, always-compare-med zero means that if one path is missing a MED attribute, it is treated as though it had a MED attribute with the value of 0. If neither option is specified, the zero option is implied.

The no form of the command means that only the MEDs of paths that have the same neighbor AS are compared.

Default

no always-compare-med

Parameters
zero

specifies that for routes learned without a MED attribute, a zero (0) value is used in the MED comparison. The routes with the lowest metric are the most preferred.

infinity

specifies that for routes learned without a MED attribute, a value of infinity (4294967295) is used in the MED comparison. This, in effect, makes these routes the least desirable.

strict-as

specifies that the MEDs of two paths are compared only if they come from the same neighboring AS

as-path-ignore
Syntax

[ipv4] [ipv6] [vpn-ipv4] [vpn-ipv6] [mvpn-ipv4] [label-ipv4] [label-ipv6]

no as-path-ignore

Context

config>router>bgp>path-selection

Description

This command specifies whether the AS path is used to determine the best BGP route.

If this command is enabled, the AS paths of incoming routes are not used in the route selection process.

When as-path-ignore is used without specifying any keywords, all keywords are configured.

The no form of the command means that the AS paths of incoming routes are used to determine the best BGP route.

Default

no as-path-ignore

Parameters
ipv4

specifies that the AS path length will be ignored for all IPv4 routes

ipv6

specifies that the AS path length will be ignored for all IPv6 routes

vpn-ipv4

specifies that the AS path length will be ignored for all VPN-IPv4 routes

vpn-ipv6

specifies that the AS path length will be ignored for all VPN-IPv6 routes

mvpn-ipv4

specifies that the AS path length will be ignored for all MVPN-IPv4 routes

label-ipv4

specifies that the AS path length will be ignored for all labeled IPv4 routes

label-ipv6

specifies that the AS path length will be ignored for all labeled IPv6 routes

bfd-enable
Syntax

[no] bfd-enable

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command enables the use of bidirectional forwarding (BFD) to control the state of the associated protocol interface. By enabling BFD on a given protocol interface, the state of the protocol interface is tied to the state of the BFD session between the local node and the remote node. The parameters used for BFD are set via the BFD command under the IP interface.

The no form of this command removes BFD from the associated IGP/BGP protocol adjacency.

Default

no bfd-enable

cluster
Syntax

cluster cluster-id

no cluster

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures the cluster ID for a route reflector server.

Route reflectors are used to reduce the number of IBGP sessions required within an AS. Normally, all BGP speakers within an AS must have a BGP peering with every other BGP speaker in the AS. A route reflector and its clients form a cluster. Peers that are not part of the cluster are considered to be non-clients.

When a route reflector receives a route, it must first select the best path from all the paths received. If the route was received from a non-client peer, then the route reflector sends the route to all clients in the cluster. If the route came from a client peer, the route reflector sends the route to all non-client peers and to all client peers except the originator.

For redundancy, a cluster can have multiple route reflectors.

The no form of the command deletes the cluster ID and effectively disables route reflection for the given group.

Default

no cluster

Parameters
cluster-id

the route reflector cluster ID, expressed in dotted-decimal notation

Values

any 32-bit number in dotted-decimal notation (0.0.0.1 to 255.255.255.255)

connect-retry
Syntax

connect-retry seconds

no connect-retry

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures the BGP connect retry timer value in seconds. When this timer expires, BGP tries to reconnect to the configured peer. This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in group) or neighbor level (only applies to specified peer). The most specific value is used.

The no form of the command used at the global level reverts to the default value.

The no form of the command used at the group level reverts to the value defined at the global level.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

120 s

Parameters
seconds

the BGP connect retry timer value, in seconds, expressed as a decimal integer

Values

1 to 65535

damping
Syntax

[no] damping

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command enables BGP route damping for learned routes that are defined within the route policy. Use damping to reduce the number of update messages sent between BGP peers and reduce the load on peers without affecting the route convergence time for stable routes. Damping parameters are set at the route policy level. See 7705 SAR Router Configuration Guide, ‟Route Policy Command Reference”.

The no form of the command disables learned route damping.

The no form of the command used at the group level reverts to the value defined at the global level.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

no damping

def-recv-evpn-encap
Syntax

def-recv-evpn-encap encap-type

no def-recv-evpn-encap

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command defines how BGP treats a received EVPN route without RFC 5512 BGP encapsulation extended community. If no encapsulation is received, BGP validates the route as MPLS.

Default

no def-recv-evpn-encap

Parameters
encap-type

specifies the default encapsulation value in the case where no RFC 5512 extended community is received in the incoming BGP-EVPN route

Values

mpls

default-route-target
Syntax

[no] default-route-target

Context

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command advertises the default RTC route towards the selected peers.

The default RTC route is a special route that has a prefix length of zero. Sending the default RTC route to a peer conveys a request to receive all VPN routes from that peer, whether or not they match the route target extended community. Advertising the default RTC route to a peer does not suppress other more specific RTC routes from being sent to that peer.

The no form of the command blocks the router from advertising the default RTC route.

Default

no default-route-target

description
Syntax

description description-string

no description

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command creates a text description stored in the configuration file for a configuration context.

The no form of the command removes the description string from the context.

Default

No description is associated with the configuration context

Parameters
string

the description character string. Allowed values are any string up to 80 characters long composed of printable, 7-bit ASCII characters. If the string contains special characters (such as #, $, or spaces), the entire string must be enclosed within double quotes.

disable-client-reflect
Syntax

[no] disable-client-reflect

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command disables the reflection of routes by the route reflector to the clients in a specific group or neighbor.

This command only disables the reflection of routes from other client peers. Routes learned from non-client peers are still reflected to all clients.

The no form re-enables client reflection of routes.

Default

no disable-client-reflect

disable-communities
Syntax

disable-communities [standard] [extended]

no disable-communities

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures BGP to disable sending communities.

Default

no disable-communities

Parameters
standard

specifies standard communities that existed before VPRNs or RFC 2547

extended

specifies BGP communities that were expanded after the concept of RFC 2547 was introduced, to include handling the route target from the VRF

disable-fast-external-failover
Syntax

[no] disable-fast-external-failover

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures BGP fast external failover.

For EBGP neighbors, this feature controls whether the router should drop an EBGP session immediately upon an interface-down event, or whether the BGP session should be kept up until the hold-time expires.

When fast external failover is disabled, the EBGP session stays up until the hold-time expires or the interface comes back up. If the BGP routes become unreachable as a result of the down IP interface, BGP withdraws the unavailable route immediately from other peers.

Default

no disable-communities

dynamic-neighbor
Syntax

dynamic-neighbor

Context

config>router>bgp>group

Description

This command enables the context to configure dynamic BGP sessions for a peer group.

prefix
Syntax

[no] prefix ip-prefix/ip-prefix-length

Context

config>router>bgp>group>dynamic-neighbor

Description

This command configures a prefix to accept dynamic BGP sessions, which are sessions from source IP addresses that do not match any configured (static) neighbor addresses.

A dynamic session is associated with the group having the longest-match prefix entry for the source IP address of the peer. There is no limit on the number of prefixes that can be configured. The group association determines local parameters that apply to the session, including the local AS, local IP address, MP-BGP families, and import and export policies.

The no form of this command removes a prefix entry.

Default

n/a

Parameters
ip-prefix/ip-prefix-length

specifies a prefix from which to accept dynamic BGP sessions

Values

ipv4-prefix — a.b.c.d (host bits must be 0)

ipv4-prefix-length — 0 to 32

ipv6-prefix — x:x:x:x:x:x:x:x (eight 16-bit pieces)

 x:x:x:x:x:x:d.d.d.d

 x — [0 to FFFF]H

 d — [0 to 255]D

ipv6-prefix-length — 0 to 128

dynamic-neighbor-limit
Syntax

dynamic-neighbor-limit peers

no dynamic-neighbor-limit

Context

config>router>bgp

config>router>bgp>group

Description

This command configures the maximum number of dynamic BGP sessions that will be accepted from remote peers associated with the global BGP instance or a specific peer group. If accepting a new dynamic session would cause either the group limit or the global limit to be exceeded, the new session attempt is rejected and a notification message is sent back to the remote peer.

The no form of this command removes the limit on the number of dynamic sessions.

Default

no dynamic-neighbor-limit

Parameters
peers

specifies the maximum number of dynamic BGP sessions

Values

1 to 320: 7705 SAR-18, 7705 SAR-8 Shelf V2

1 to 128: 7705 SAR-X

1 to 64: 7705 SAR-A, 7705 SAR-Ax, 7705 SAR-H, 7705 SAR-Hc, 7705 SAR-M, 7705 SAR-Wx

enable-peer-tracking
Syntax

[no] enable-peer-tracking

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command enables BGP peer tracking. BGP peer tracking allows a BGP peer to be dropped immediately if the route used to resolve the BGP peer address is removed from the IP routing table and there is no alternative available. The BGP peer will not wait for the hold timer to expire; therefore, the BGP reconvergence process is accelerated.

The no form of the command disables peer tracking.

Default

no enable-peer-tracking

enable-rr-vpn-forwarding
Syntax

[no] enable-rr-vpn-forwarding

Context

config>router>bgp

Description

This command enables a route reflector of VPN-IP routes to be deployed in the data path between two BGP peers (a peer X and a peer Y) in a next-hop resolution.

All received VPN-IP routes are imported into a table that is used to resolve the BGP next hops. The next hop of a VPN-IP route that is imported from peer X and selected as having the best path by the table is advertised to peer Y (the next-hop-self command must be set for peer Y or a next-hop action must be used in an export policy that is applied to peer Y in order for the next-hop to be advertised to peer Y).

A new VPN service label value is then allocated for the VPN-IP route. This new label is advertised to peer Y and a label swap operation is then performed by the IOM.

The no form of the command disables the advertising of a new VPN service label from one BGP peer to another.

Default

no enable-rr-vpn-forwarding

export
Syntax

export policy-name [policy-name…(up to 5 max)]

no export [policy-name]

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command specifies the export route policy used to determine which routes are advertised to peers. Route policies are configured in the config>router>policy-options context. See the section on ‟Route Policy” in the 7705 SAR Router Configuration Guide.

This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in group) or neighbor level (only applies to specified peer). The most specific level is used.

When multiple policy names are specified, the policies are evaluated in the order in which they are specified. A maximum of five (5) policy names can be configured. The first policy that matches is applied.

When multiple export commands are issued, the last command entered overrides the previous command.

When no export policies are specified, BGP routes are advertised and non-BGP routes are not advertised (by default).

The BGP advertise-inactive, add-paths, and export policy commands can be configured such that active, non-BGP routes are advertised. For more information, see Advertise-Inactive, Add-Paths, and Export Policy Interaction.

The no form of the command removes the policy association with the BGP instance. To remove association of all policies, use the no export command without arguments.

Default

no export

Parameters
policy-name

the route policy name. Allowed values are any string up to 32 characters long composed of printable, 7-bit ASCII characters. If the string contains special characters (such as #, $, or spaces), the entire string must be enclosed within double quotes.

family
Syntax

family [ipv4] [vpn-ipv4] [ipv6] [vpn-ipv6] [mvpn-ipv4] [route-target] [evpn] [label-ipv4] [label-ipv6] [bgp-ls]

no family

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command specifies the address family or families to be supported over BGP peerings in the base router. One or more address families can be specified in a single command. To add an address family to the currently configured families, reissue the command and include the current families in addition to any new family.

The no form of the command removes the specified address family from the associated BGP peerings. If an address family is not specified, the supported address family is reset to the default.

Default

ipv4

Parameters
ipv4

supports IPv4 routing information

vpn-ipv4

exchanges VPN-IPv4 routing information

ipv6

supports IPv6 routing information

vpn-ipv6

exchanges VPN-IPv6 routing information

mvpn-ipv4

exchanges MVPN-IPv4 routing information

route-target

exchanges RTC routing information

evpn

exchanges EVPN routing information

label-ipv4

supports labeled IPv4 routing information

label-ipv6

supports labeled IPv6 routing information

bgp-ls

supports BGP-LS routing information

graceful-restart
Syntax

[no] graceful-restart

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

The command enables procedures for BGP graceful restart (GR) helper—the receiving router role, as defined in the RFC 4724 standard—for all received IPv4 and VPN-IPv4 routes. In order for helper mode to be available for a particular address family, both peers must signal GR support for the address family during capability negotiation.

When a neighbor covered by GR helper mode restarts its control plane, the forwarding of traffic can continue uninterrupted while the session is being re-established and routes are relearned.

The no form of the command disables graceful restart and removes all graceful restart configurations in the BGP instance.

Default

no graceful-restart

stale-routes-time
Syntax

stale-routes-time time

no stale-routes-time

Context

config>router>bgp>graceful-restart

config>router>bgp>group>graceful-restart

config>router>bgp>group>neighbor>graceful-restart

Description

This command configures the maximum amount of time in seconds that stale routes should be maintained after a graceful restart is initiated.

The no form of the command resets the stale routes time back to the default value.

Default

360 s

Parameters
time

the amount of time that stale routes should be maintained after a graceful restart is initiated

Values

1 to 3600 s

group
Syntax

[no] group name

Context

config>router>bgp

Description

This command creates a context to configure a BGP peer group.

The no form of the command deletes the specified peer group and all configurations associated with the peer group. The group must be shut down before it can be deleted.

Default

no group

Parameters
name

the peer group name. Allowed values are any string up to 32 characters long composed of printable, 7-bit ASCII characters. If the string contains special characters (such as #, $, or spaces), the entire string must be enclosed within double quotes.

hold-time
Syntax

hold-time seconds [min seconds2]

no hold-time

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures the BGP hold time, expressed in seconds.

The BGP hold time specifies the maximum time BGP waits between successive messages (either Keepalive or Update) from its peer, before closing the connection. This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in group) or neighbor level (only applies to specified peer). The most specific value is used.

The min option ensures a minimum hold time for a BGP session that is independent of the hold time advertised in a received Open message.

Even though the 7705 SAR implementation allows setting the keepalive time separately, the configured keepalive timer is overridden by the hold-time value under the following circumstances.

  • If the specified hold-time is less than the configured keepalive time, then the operational keepalive time is set to a third of the hold-time; the configured keepalive time is not changed.

  • If the hold-time is set to 0, then the operational value of the keepalive time is set to 0; the configured keepalive time is not changed. This means that the connection with the peer is up permanently and no keepalive packets are sent to the peer.

The no form of the command used at the global level reverts to the default value.

The no form of the command used at the group level reverts to the value defined at the global level.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

90 s

Parameters
seconds

the hold time, in seconds, expressed as a decimal integer. A value of 0 indicates that the connection to the peer is permanently up.

Values

0, 3 to 65535

seconds2

the minimum hold time, in seconds, that will be accepted for the session. If the peer proposes a hold time lower than this value, the session attempt will be rejected.

Values

0, 3 to 65535

ibgp-multipath
Syntax

[no] ibgp-multipath

Context

config>router>bgp

Description

This command enables IBGP multipath load balancing when adding BGP routes to the route table if the route resolving the BGP next-hop offers multiple next-hops.

The no form of the command disables the IBGP multipath load balancing feature.

Default

no ibgp-multipath

import
Syntax

import policy-name [policy-name…(up to 5 max)]

no import [policy-name]

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command specifies the import route policy to be used to determine which routes are accepted from peers. Route policies are configured in the config>router>policy-options context. See the section on ‟Route Policy” in the 7705 SAR Router Configuration Guide.

This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in group) or neighbor level (only applies to specified peer). The most specific level is used.

When multiple policy names are specified, the policies are evaluated in the order in which they are specified. A maximum of five (5) policy names can be specified. The first policy that matches is applied.

When multiple import commands are issued, the last command entered will override the previous command.

When an import policy is not specified, BGP routes are accepted by default.

The no form of the command removes the policy association with the BGP instance. To remove association of all policies, use no import without arguments.

Default

no import

Parameters
policy-name

the route policy name. Allowed values are any string up to 32 characters long composed of printable, 7-bit ASCII characters. If the string contains special characters (such as #, $, or spaces), the entire string must be enclosed within double quotes.

keepalive
Syntax

keepalive seconds

no keepalive

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures the BGP keepalive timer. A Keepalive message is sent every time this timer expires.

The keepalive parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in group) or neighbor level (only applies to specified peer). The most specific value is used. The keepalive value is generally one-third of the hold-time interval. Even though the 7705 SAR implementation allows the keepalive value and the hold-time interval to be independently set, under the following circumstances, the configured keepalive value is overridden by the hold-time value.

  • If the specified keepalive value is greater than the configured hold-time, then the specified value is ignored, and the keepalive value is set to one third of the current hold-time value.

  • If the specified hold-time interval is less than the configured keepalive value, then the keepalive value is reset to one third of the specified hold-time interval.

  • If the hold-time interval is set to 0, then the configured value of the keepalive value is ignored. This means that the connection with the peer is up permanently and no keepalive packets are sent to the peer.

The no form of the command used at the global level reverts to the default value.

The no form of the command used at the group level reverts to the value defined at the global level.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

30 s

Parameters
seconds

the keepalive timer, in seconds, expressed as a decimal integer

Values

0 to 21845

label-preference
Syntax

label-preference value

no label-preference

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures the route preference for routes learned from labeled unicast peers.

This command can be configured at three levels:

  • global level — applies to all peers

  • group level — applies to all peers in the peer group

  • neighbor level — applies only to the specified peer

The most specific value is used.

The lower the preference value, the higher the chance of the route being the active route.

The no form of the command used at the global level reverts to the default value of 170.

The no form of the command used at the group level reverts to the value defined at the global level.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

no label-preference

Parameters
value

specifies the route preference value

Values

1 to 255

Default

170 (global level)

link-state-export-enable
Syntax

[no] link-state-export-enable

Context

config>router>bgp

Description

This command enables the export of link-state information from the BGP-LS address family into the local Traffic Engineering Database (TED).

The no form of this command disables the export of link-state information into the TED.

Default

no link-state-export-enable

link-state-import-enable
Syntax

[no] link-state-import-enable

Context

config>router>bgp

Description

This command enables the import of link-state information into the BGP-LS address family for advertisement to other BGP neighbors.

The no form of this command disables the import of link-state information into the BGP-LS address family.

Default

no link-state-import-enable

local-address
Syntax

local-address ip-address

no local-address

Context

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures the local IP address used by the group or neighbor when communicating with BGP peers.

Outgoing connections use the local-address as the source of the TCP connection when initiating connections with a peer.

When a local address is not specified at the group level, the 7705 SAR uses the system IP address when communicating with IBGP peers and uses the interface address for directly connected EBGP peers. When a local address is not specified at the neighbor level, the neighbor uses the value defined at the group level.

The no form of the command removes the configured local address for BGP.

Default

no local-address

Parameters
ip-address

the local address. The allowed value is a valid routable IP address on the router, either an interface or system IP address.

Values

ipv4-address:   a.b.c.d (host bits must be 0)

ipv6-address: x:x:x:x:x:x:x:x (eight 16-bit pieces)

 x:x:x:x:x:x:d.d.d.d

 x: [0 to FFFF]H

 d: [0 to 255]D

local-as
Syntax

local-as as-number [private]

no local-as

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures a BGP virtual autonomous system (AS) number.

In addition to the AS number configured for BGP in the config>router>autonomous- system context, a virtual (local) AS number is configured. The virtual AS number is added to the as-path attribute before the router’s AS number makes the virtual AS the second AS in the AS path.

This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in group) or neighbor level (only applies to specified peer). By specifying this parameter at each neighbor level, it is possible to have a separate AS number per EBGP session.

When a command is entered multiple times for the same AS, the last command entered is used in the configuration. The private attribute can be added or removed dynamically by reissuing the command.

Changing the local AS at the global level in an active BGP instance causes the BGP instance to restart with the new local AS number.

Changing the local AS at the group level in an active BGP instance causes BGP to re-establish the peer relationships with all peers in the group with the new local AS number.

Changing the local AS at the neighbor level in an active BGP instance causes BGP to re-establish the peer relationship with the new local AS number.

This is an optional command and can be used in the following situation.

Example: Provider router P is moved from AS1 to AS2. The customer router that is connected to P, however, is configured to belong to AS1. To avoid reconfiguring the customer router, the local-as value on router P can be set to AS1. Thus, router P adds AS1 to the as-path message for routes it advertises to the customer router.

The no form of the command used at the global level will remove any virtual AS number configured.

The no form of the command used at the group level reverts to the value defined at the global level.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

no local-as

Parameters
as-number

the virtual autonomous system number expressed as a decimal integer

Values

1 to 4294967295

private

specifies that the local AS is hidden in paths learned from the peering

local-preference
Syntax

local-preference local-preference

no local-preference

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures the default value of the BGP local preference attribute if it is not already specified in incoming routes.

This value is used if the BGP route arrives from a BGP peer without the local-preference integer set.

The specified value can be overridden by any value set via a route policy. This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in group) or neighbor level (only applies to specified peer). The most specific value is used.

The no form of the command at the global level specifies that incoming routes with local preference set are not overridden and routes arriving without local preference set are interpreted as if the route had a local preference value of 100.

The no form of the command used at the group level reverts to the value defined at the global level.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

no local-preference

Parameters
local-preference

the local preference value to be used as the override value, expressed as a decimal integer

Values

0 to 4294967295

loop-detect
Syntax

loop-detect {drop-peer | discard-route | ignore-loop | off}

no loop-detect

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures how the BGP peer session handles loop detection in the AS path.

This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in group) or neighbor level (only applies to specified peer). The most specific value is used.

When applied to an ongoing BGP peer session, this command does not take effect until the BGP peer session is re-established.

The no form of the command used at the global level reverts to the default (ignore- loop).

The no form of the command used at the group level reverts to the value defined at the global level.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

ignore-loop

Parameters
drop-peer

sends a notification to the remote peer and drops the session

discard-route

discards routes received from a peer with the same AS number as the router itself. This option prevents routes looped back to the router from being added to the routing information base and consuming memory. When this option is changed, the change will not be active for an established peer until the connection is re-established for the peer.

ignore-loop

ignores routes with loops in the AS path, but maintains peering

off

disables loop detection

med-out
Syntax

med-out {number | igp-cost}

no med-out

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command is used to advertise the Multi-Exit Discriminator (MED) to BGP peers and assign the path value if the MED is not already set via a route policy (the specified value can be overridden by a MED value that is set via a route policy using the metric command. See the 7705 SAR Router Configuration Guide, ‟Route Policy Configuration Commands”).

The no form of the command used at the global level reverts to the default where the MED is not advertised.

The no form of the command used at the group level reverts to the value defined at the global level.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

no med-out (the MED is not advertised)

Parameters
number

the MED path value

Values

0 to 4294967295

igp-cost

the MED is set to the IGP cost of the IP prefix that is defined via a route policy

min-route-advertisement
Syntax

min-route-advertisement seconds

no min-route-advertisement

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures the minimum interval, in seconds, at which a prefix can be advertised to a peer.

This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in group) or neighbor level (only applies to specified peer). The most specific value is used.

The no form of the command used at the global level reverts to the default.

The no form of the command used at the group level reverts to the value defined at the global level.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

30 s

Parameters
seconds

the minimum route advertising interval, in seconds, expressed as a decimal integer

Values

2 to 255

multihop
Syntax

multihop ttl-value

no multihop

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures the time to live (TTL) value at an originating BGP peer. The TTL value is entered in the IP header of packets that are sent to a terminating BGP peer that is multiple hops away.

The no form of the command used at the global level reverts to the default value.

The no form of the command used at the group level reverts to the value defined at the global level.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

1 — EBGP peers are directly connected

64 — IBGP peer

Parameters
ttl-value

the TTL value that will be entered in the IP header of packets that are sent to a terminating BGP peer that is multiple hops away

Values

1 to 255

multipath
Syntax

multipath integer

no multipath

Context

config>router>bgp

Description

This command enables BGP multipath.

When multipath is enabled, BGP load-shares traffic across multiple links. Multipath can be configured to load-share traffic across a maximum of 16 routes. If the equal-cost routes available are more than the configured value, then routes with the lowest next-hop IP address value are chosen.

This configuration parameter is set at the global level (applies to all peers).

Multipath is disabled if the value is set to 1. When multipath is disabled and multiple equal-cost routes are available, the route with the lowest next-hop IP address will be used.

The no form of the command reverts to the default where multipath is disabled.

Default

no multipath

Parameters
integer

the number of equal-cost routes to use for multipath routing. If more equal-cost routes exist than the configured value, routes with the lowest next-hop value are chosen. Setting this value to 1 disables multipath.

Values

1 to 16

mvpn-vrf-import-subtype-new
Syntax

[no] mvpn-vrf-import-subtype-new

Context

config>router>bgp

Description

This command enables the type/subtype in advertised routes to be encoded as 0x010b (extended community type: transitive IPv4-address-specific VRF route import).

The no form of the command encodes the type/subtype as 0x010a (extended community type: transitive IPv4-address-specific L2VPN identifier), in order to preserve backwards compatibility.

Default

no mvpn-vrf-import-subtype-new

next-hop-resolution
Syntax

next-hop-resolution

Context

config>router>bgp

Description

This command enables the context to configure next-hop resolution parameters.

label-route-transport-tunnel
Syntax

label-route-transport-tunnel

Context

config>router>bgp>next-hop-res

Description

This command enables the context to configure options for the next-hop resolution of BGP labeled routes (VPN-IP and labeled unicast) using tunnels in the Tunnel Table Manager (TTM). The context allows the selection of different tunnel resolution options for different types of BGP labeled routes: labeled unicast IPv4, labeled unicast IPv6, and VPN-IP routes (both VPN-IPv4 and VPN-IPv6).

By default (if this context and the resolution options are not configured), these routes resolve only to LDP tunnels.

family
Syntax

family family

Context

config>router>bgp>next-hop-res>lbl-rt-tunn

Description

This command configures the address family context for configuring next-hop resolution of BGP label routes.

Parameters
family

specifies and enters the context for configuring next-hop-resolution options

Values

vpn, label-ipv4, label-ipv6

resolution
Syntax

resolution {any | filter | disabled}

Context

config>router>bgp>next-hop-res>lbl-rt-tunn>family

Description

This command configures the resolution mode in the resolution of BGP label routes using tunnels to BGP peers.

If the resolution option is explicitly set to disabled, the default binding to LDP tunnels resumes. If resolution is set to any, any supported tunnel type is allowed and the selection is based on the lowest numerical TTM preference value. The resolution must be set to filter to activate the list of tunnel types configured under the resolution-filter command.

Parameters
any

enables the binding to any supported tunnel type in the BGP label route context following TTM preference

filter

enables the binding to the subset of tunnel types configured under resolution-filter

disabled

disables the resolution of BGP label routes using tunnels to BGP peers

resolution-filter
Syntax

resolution-filter

Context

config>router>bgp>next-hop-res>lbl-rt-tunn>family

Description

This command enables the context to configure the subset of tunnel types that can be used in the resolution of BGP label routes.

The following tunnel types are supported in a BGP label route context (in order of preference from most to least preferred): RSVP, SR-TE, LDP, SR-OSPF, and SR-ISIS.

Only the tunnel types specified using the resolution-filter command are selected, following the TTM preference.

The resolution must be set to filter to activate the list of tunnel types configured under resolution-filter.

ldp
Syntax

[no] ldp

Context

config>router>bgp>next-hop-res>lbl-rt-tunn>family>res-filter

Description

This command selects LDP tunneling for next-hop resolution.

The ldp command instructs BGP to search for an LDP LSP with a FEC prefix corresponding to the address of the BGP next hop.

rsvp
Syntax

[no] rsvp

Context

config>router>bgp>next-hop-res>lbl-rt-tunn>family>res-filter

Description

This command selects RSVP tunneling for next-hop resolution.

The rsvp command instructs BGP to search for the best metric RSVP-TE LSP to the BGP next-hop address. The address can correspond to the system interface or to another loopback interface used by the BGP instance on the remote node. The LSP metric is provided by MPLS in the tunnel table. If there are multiple RSVP-TE LSPs with the same lowest metric, BGP selects the LSP with the lowest tunnel ID.

sr-isis
Syntax

[no] sr-isis

Context

config>router>bgp>next-hop-res>lbl-rt-tunn>family>res-filter

Description

This command selects the Segment Routing (SR) tunnel type programmed by an IS-IS instance in the TTM for next-hop resolution.

When the sr-isis command is enabled, a tunnel to the BGP next hop is selected in the TTM from the lowest-numbered IS-IS instance.

sr-ospf
Syntax

[no] sr-ospf

Context

config>router>bgp>next-hop-res>lbl-rt-tunn>family>res-filter

Description

This command selects the Segment Routing (SR) tunnel type programmed by OSPF in the TTM for next-hop resolution.

When the sr-ospf command is enabled, a tunnel to the BGP next hop is selected in the TTM from OSPF.

sr-te
Syntax

[no] sr-te

Context

config>router>bgp>next-hop-res>lbl-rt-tunn>family>res-filter

Description

This command selects the Segment Routing (SR) tunnel type programmed by a traffic engineered (TE) instance in the TTM for next-hop resolution.

The sr-te command initiates a search for the best metric SR-TE LSP to the BGP next-hop address. The LSP metric is provided by MPLS in the tunnel table. If there are multiple SR-TE LSPs with the same lowest metric, BGP selects the LSP with the lowest tunnel ID.

policy
Syntax

policy policy-name

no policy

Context

config>router>bgp>next-hop-resolution

Description

This command specifies the name of a policy statement to use with the BGP next-hop resolution process. The policy controls which IP routes in the RTM are eligible to resolve the BGP next-hop addresses of IPv4 and IPv6 routes. The policy has no effect on the resolution of BGP next hops to MPLS tunnels. If a BGP next hop of an IPv4 or IPv6 route is resolved in the RTM and the longest matching route for the next-hop address is an IP route that is rejected by the policy, the route is unresolved; if the route is accepted by the policy, it becomes the resolving route.

If the no form of the command is used, the default next-hop-resolution policy is to use the longest matching active route in the RTM that is not a BGP route or an aggregate route.

Default

no policy

Parameters
policy-name

specifies an existing route policy name. Route policies are configured in the config>router>policy-options context.

neighbor
Syntax

[no] neighbor ip-address

Context

config>router>bgp>group

Description

This command creates a BGP peer/neighbor instance within the context of the BGP group.

This command can be issued repeatedly to create multiple peers and their associated configurations.

The no form of the command is used to remove the specified neighbor and the entire configuration associated with the neighbor. The neighbor must be administratively shut down before it can be deleted. If the neighbor is not shut down, the command will not result in any action except a warning message on the CLI indicating that the neighbor is still administratively up.

Default

no neighbor — no neighbors are defined

Parameters
ip-address

the IP address of the BGP neighbor

Values

ipv4-address:  a.b.c.d

split-horizon
Syntax

[no] split-horizon

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command enables the use of split horizon. Split horizon prevents routes from being reflected back to a peer that sends the best route. It applies to routes of all address families and to any type of sending peer: EBGP and IBGP.

By default, split horizon is not enabled, meaning that no effort is taken to prevent a best route from being reflected back to the sending peer.

Note: Enabling split horizon may have a detrimental impact on peer and route scaling; therefore, operators are encouraged to use it only when absolutely needed.
Default

no split-horizon

next-hop-self
Syntax

[no] next-hop-self

Context

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures the group or neighbor to always set the next-hop path attribute to its own physical interface when advertising to a peer.

This command is primarily used to avoid third-party route advertisements when connected to a multi-access network.

The no form of the command used at the group level allows third-party route advertisements in a multi-access network.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

no next-hop-self

outbound-route-filtering
Syntax

[no] outbound-route-filtering

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command opens the configuration tree for sending or accepting BGP filter lists from peers (outbound route filtering (ORF)).

Default

no outbound-route-filtering

extended-community
Syntax

[no] extended-community

Context

config>router>bgp>outbound-route-filtering

config>router>bgp>group>outbound-route-filtering

config>router>bgp>group>neighbor>outbound-route-filtering

Description

This command opens the configuration tree for sending or accepting extended-community-based BGP filters. In order for the no version of the command to work, all sub-commands (send-orf, accept-orf) must be removed first.

Default

no extended-community

accept-orf
Syntax

[no] accept-orf

Context

config>router>bgp>outbound-route-filtering>extended-community

config>router>bgp>group>outbound-route-filtering>extended-community

config>router>bgp>group>neighbor>outbound-route-filtering>extended-community

Description

This command instructs the router to negotiate the receive capability in the BGP outbound route filtering (ORF) negotiation with a peer, and to accept filters that the peer wishes to send.

The no form of the command causes the router to remove the accept capability in the BGP ORF negotiation with a peer, and to clear any existing ORF filters that are currently in place.

Default

no accept-orf

send-orf
Syntax

send-orf [comm-id...(up to 32 max)]

no send-orf [comm-id]

Context

config>router>bgp>outbound-route-filtering>extended-community

config>router>bgp>group>outbound-route-filtering>extended-community

config>router>bgp>group>neighbor>outbound-route-filtering>extended-community

Description

This command instructs the router to negotiate the send capability in the BGP outbound route filtering (ORF) negotiation with a peer.

This command also causes the router to send a community filter, prefix filter, or AS path filter configured as an inbound filter on the BGP session to its peer as an ORF Action ADD.

The no form of this command causes the router to remove the send capability in the BGP ORF negotiation with a peer.

The no form also causes the router to send an ORF remove action for a community filter, prefix filter, or AS path filter configured as an inbound filter on the BGP session to its peer.

If the comm-id parameters are not exclusively route target communities, the router will extract appropriate route targets and use those. If, for some reason, the comm-id parameters specified contain no route targets, the router will not send an ORF.

Default

no send-orf

Parameters
comm-id

any community policy that consists exclusively of route target extended communities. If the policy is not specified, then the ORF policy is automatically generated from configured route target lists, accepted client route target ORFs, and locally configured route targets.

Values

comm-id:  target: {ip-addr:comm-val | as-number:ext-  comm-val}

ip-addr:  a.b.c.d

comm-val:  0 to 65535

as-number:  0 to 65535

ext-comm-val:  0 to 4294967295

passive
Syntax

[no] passive

Context

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command enables and disables passive mode for the BGP group or neighbor. When in passive mode, BGP will not attempt to actively connect to the configured BGP peers but responds only when it receives a connect open request from the peer.

The no form of the command used at the group level disables passive mode, and BGP actively attempts to connect to its peers.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

no passive

peer-as
Syntax

peer-as as-number

no peer-as

Context

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures the autonomous system number for the remote peer. The peer AS number must be configured for each configured peer.

For IBGP peers, the peer AS number must be the same as the autonomous system number of this router configured under the global level.

This command may be configured under the group level for all neighbors in a particular group.

Default

no AS numbers are defined

Parameters
as-number

the autonomous system number, expressed as a decimal integer

Values

1 to 4294967295

peer-tracking-policy
Syntax

peer-tracking-policy policy-name

no peer-tracking-policy

Context

config>router>bgp

Description

This command specifies the name of a policy statement to use with the BGP peer-tracking function on the BGP sessions where the peer-tracking-policy command is enabled. The policy controls which IP routes in the RTM are eligible to indicate reachability of IPv4 and IPv6 BGP neighbor addresses. If the longest matching route in the RTM for a BGP neighbor address is an IP route that is rejected by the policy or a BGP route accepted by the policy, or if there is no matching route, the neighbor is considered unreachable and BGP tears down the peering session and keeps it in the idle state until a valid route is available again and accepted by the policy.

The no form of the command defaults to using the longest matching active route in the RTM that is not an aggregate route.

Default

no peer-tracking-policy

Parameters
policy-name

specifies an existing route policy name. Route policies are configured in the config>router>policy-options context.

preference
Syntax

preference preference

no preference

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures the route preference for routes learned from the configured peers.

This configuration parameter can be set at three levels: global level (applies to all peers), group level (applies to all peers in group) or neighbor level (only applies to specified peer). The most specific value is used.

The lower the preference, the higher the chance of the route being the active route. The 7705 SAR assigns the highest default preference to BGP routes as compared to routes that are direct, static, or learned via MPLS or OSPF.

The no form of the command used at the global level reverts to the default value.

The no form of the command used at the group level reverts to the value defined at the global level.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

170

Parameters
preference

the route preference, expressed as a decimal integer

Values

1 to 255

prefix-limit
Syntax

prefix-limit family limit [threshold percentage] [idle-timeout {minutes | forever} | log-only] [post-import]

no prefix-limit family

Context

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures the maximum number of BGP routes that can be received from a peer before administrative action is taken. The administrative action can be the generation of a log event or the taking down of the session. If a session is taken down, it can be brought back up automatically after an idle-timeout period or it can be configured to stay down (forever) until the operator performs a reset.

The prefix-limit command allows each address family to have its own limit; a set of address family limits can be applied to one neighbor or to all neighbors in a group.

The no form of the command removes the prefix-limit.

Default

No prefix limits for any address family

Parameters
family

specifies the address family to which the limit applies

Values

ipv4, vpn-ipv4, ipv6, vpn-ipv6, mvpn-ipv4, route-target, label-ipv4, label-ipv6, evpn, bgp-ls

limit

specifies the number of routes that can be learned from a peer, expressed as a decimal integer

Values

1 to 4294967295

percentage

specifies the threshold value, as a percentage, that triggers a warning message to be sent

Values

1 to 100

minutes

specifies the length of time, in minutes, before automatically re-establishing a session

Values

1 to 1024

forever

specifies that the session is re-established only after the clear router bgp command is executed

log-only

enables a warning message to be sent at the specified threshold percentage and also when the limit is reached. However, the BGP session is not taken down.

post-import

specifies that the limit should be applied only to the number of routes that are accepted by import policies

rapid-update
Syntax

rapid-update [mvpn-ipv4] [evpn]

no rapid-update

Context

config>router>bgp

Description

This command enables BGP rapid update for specified address families.

The no form of the command disables BGP rapid update.

Default

no rapid-update

Parameters
mvpn-ipv4

specifies BGP rapid update for the MVPN-IPv4 family

evpn

specifies BGP rapid update for the EVPN family

rapid-withdrawal
Syntax

[no] rapid-withdrawal

Context

config>router>bgp

Description

This command disables the delay on issuing BGP withdrawals.

By default, BGP withdrawals (messages containing the routes that are no longer valid) are delayed up to the min-route-advertisement to allow for efficient packing of BGP Update messages. However, when the rapid-withdrawal command is enabled, the delay on sending BGP withdrawals is disabled.

The no form of the command returns BGP withdrawal processing to its default behavior.

Default

no rapid-withdrawal

remove-private
Syntax

[no] remove-private [limited]

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command allows all private AS numbers to be removed from the AS path before advertising them to BGP peers. The no form of the command includes private AS numbers in the AS path attribute.

If the limited keyword is included, only the leading private ASNs up to the first public ASN are removed.

When the remove-private parameter is set at the global level, it applies to all peers regardless of group or neighbor configuration. When the parameter is set at the group level, it applies to all peers in the group regardless of the neighbor configuration.

The 7705 SAR recognizes the set of AS numbers that are defined by IANA as private. These are AS numbers in the range 64512 through 65535, inclusive.

The no form of the command used at the global level reverts to the default value.

The no form of the command used at the group level reverts to the value defined at the global level.

The no form of the command used at the neighbor level reverts to the value defined at the group level.

Default

no remove-private

rib-management
Syntax

rib-management

Context

config>router>bgp

Description

This command enables the context to configure RIB management parameters. Under the RIB management context are options for ipv4, ipv6, label-ipv4, and label-ipv6.

route-table-import
Syntax

route-table-import policy-name

no route-table-import

Context

config>router>bgp>rib-management>ipv4

config>router>bgp>rib-management>ipv6

config>router>bgp>rib-management>label-ipv4

config>router>bgp>rib-management>label-ipv6

Description

This command specifies the name of a route policy to control the importation of active routes from the IP route table into one of the BGP RIBs.

If the route-table-import command is not configured, or if the command refers to an empty policy, all non-BGP routes from the IP route table are imported into the applicable RIB.

If the route-table-import command is configured, routes that are dropped or rejected by the configured policy are not installed in the associated RIB. Rejected routes cannot be advertised to BGP peers associated with the RIB, but they can still be used to resolve BGP next hops of routes in that RIB. If the active route for a prefix is rejected by the route-table-import policy, the best BGP route for that prefix in the BGP RIB can be advertised to peers as though it is used.

Aggregate routes are always imported into the applicable RIB, independent of the route-table-import policy.

Route modifications specified in the actions of a route-table-import policy are ignored and have no effect on the imported routes.

Default

no route-table-import

Parameters
policy-name

specifies the name of a policy statement; the policy statement must already have been created

route-target-list
Syntax

route-target-list comm-id [comm-id ..(up to 15 max)]

no route-target-list [comm-id]

Context

config>router>bgp

Description

This command specifies the route targets to be accepted from and advertised to peers. If the route-target-list is a non-null list, only routes with one or more of the specified route targets are accepted from or advertised to peers.

This command is only applicable if the router is a route-reflector server.

The route-target-list is assigned at the global level and applies to all peers connected to the system.

The no form of the command with a specified route target community removes the community from the route-target-list.

The no form of the command entered without a route target community removes all communities from the list.

Default

no route-target-list

Parameters
comm-id

the route target community

Values

target:{ip-addr:comm-val | 2byte-asnumber:ext-comm-val | 4-byte-asnumber:comm-val}

Where:

ip-addr                     a.b.c.d

comm-val                  0 to 65535

2-byte-asnumber     0 to 65535

ext-comm-val           0 to 4294967295

4-byte-asnumber     0 to 4294967295

router-id
Syntax

router-id ip-address

no router-id

Context

config>router>bgp

Description

This command specifies the router ID to be used with this BGP instance. If no router ID is specified, the system interface IP address is used.

Changing the BGP router ID on an active BGP instance causes the BGP instance to restart with the new router ID. The router ID must be set to a valid host address.

Default

no router-id

Parameters
ip-address

the router ID, expressed in dotted-decimal notation. The allowed value is a valid routable IP address on the router, either an interface or system IP address. It is highly recommended that this address be the system IP address.

Values

a.b.c.d

shutdown
Syntax

[no] shutdown

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command administratively disables an entity. When disabled, an entity does not change, reset, or remove any configuration settings or statistics.

The operational state of the entity is disabled as well as the operational state of any entities contained within. Many objects must be shut down before they may be deleted.

The no form of this command administratively enables an entity.

Unlike other commands and parameters where the default state is not indicated in the configuration file, the shutdown and no shutdown states are always indicated in system-generated configuration files.

Default administrative states for services and service entities are described below in Special Cases.

The no form of the command places an entity in an administratively enabled state.

Special Cases
BGP Global

the BGP protocol is created in the no shutdown state

BGP Group

BGP groups are created in the no shutdown state

BGP Neighbor

BGP neighbors/peers are created in the no shutdown state

ttl-security
Syntax

ttl-security min-ttl-value

no ttl-security

Context

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command configures TTL security parameters for incoming packets. When the feature is enabled, BGP accepts incoming IP packets from a peer only if the TTL value in the packet is greater than or equal to the minimum TTL value configured for that peer.

The no form of the command disables TTL security.

Default

no ttl-security

Parameters
min-ttl-value

the minimum TTL value for an incoming packet

Values

1 to 255

Default

1

vpn-apply-export
Syntax

[no] vpn-apply-export

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command causes the base instance BGP export route policies to be applied to VPN-IPv4 routes.

The no form of the command disables the application of the base instance BGP export route policies to VPN-IPv4 routes.

Default

no vpn-apply-export

vpn-apply-import
Syntax

[no] vpn-apply-import

Context

config>router>bgp

config>router>bgp>group

config>router>bgp>group>neighbor

Description

This command causes the base instance BGP import route policies to be applied to VPN-IPv4 routes.

The no form of the command disables the application of the base instance BGP import route policies to VPN-IPv4 routes.

Default

no vpn-apply-import

Other BGP-Related Commands
aggregate
Syntax

aggregate ip-prefix/ip-prefix-length [summary-only]

no aggregate ip-prefix/ip-prefix-length

Context

config>router

Description

This command creates an aggregate route.

Use this command to group a number of routes with common prefixes into a single entry in the routing table. This reduces the number of routes that need to be advertised by this router and reduces the number of routes in the routing tables of downstream routers.

Both the original components and the aggregated route (source protocol aggregate) are offered to the Routing Table Manager (RTM). Subsequent policies can be configured to assign protocol-specific characteristics, such as the OSPF tag, to aggregate routes.

Multiple entries with the same prefix but a different mask can be configured; routes are aggregated to the longest mask. If one aggregate is configured as 10.0/16 and another as 10.0.0/24, then route 10.0.128/17 would be aggregated into 10.0/16 and route 10.0.0.128/25 would be aggregated into 10.0.0/24. If multiple entries are made with the same prefix and the same mask, the previous entry is overwritten.

The no form of the command removes the aggregate.

Default

no aggregate

Parameters
ip-prefix/ip-prefix-length

the destination address of the aggregate route in dotted-decimal notation

Values

ip-prefix:                   a.b.c.d (host bits must be 0)

ip-prefix-length:        0 to 32

summary-only

suppresses advertisement of more specific component routes for the aggregate. To remove the summary-only option, enter the same aggregate command without the summary-only parameter.

autonomous-system
Syntax

autonomous-system as-number

no autonomous-system

Context

config>router

Description

This command configures the autonomous system (AS) number for the router. A router can only belong to one AS. An AS number is a globally unique number within an AS. This number is used to exchange exterior routing information with neighboring ASs and as an identifier of the AS itself.

If the AS number is changed on a router with an active BGP instance, the new AS number is not used until the BGP instance is restarted either by administratively disabling/enabling (shutdown/no shutdown) the BGP instance or rebooting the system with the new configuration.

Default

no autonomous-system

Parameters
as-number

the autonomous system number expressed as a decimal integer

Values

1 to 4294967295

router-id
Syntax

router-id ip-address

[no] router-id

Context

config>router

Description

This command configures the router ID for the router instance.

The router ID is used by both OSPF and BGP routing protocols in this instance of the routing table manager. IS-IS uses the router ID value as its system ID.

When configuring a new router ID, protocols are not automatically restarted with the new router ID. The next time a protocol is initialized, the new router ID is used. This can result in an interim period of time when different protocols use different router IDs.

To force the new router ID to be used, issue the shutdown and no shutdown commands for each protocol that uses the router ID, or restart the entire router.

The no form of the command reverts to the default value.

Default

The system uses the system interface address (which is also the loopback address). If a system interface address is not configured, use the last 32 bits of the chassis MAC address.

Parameters
ip-address

32-bit router ID, expressed in dotted-decimal notation or as a decimal value

Show Commands

Note: The following command outputs are examples only; actual displays may differ depending on supported functionality and user configuration.
router
Syntax

router [router-instance]

router service-name service-name

Context

show

Description

The command displays router instance information.

Parameters
router-instance

specifies either the router name or service ID

Values

router-name:  Base, management

service-id:  1 to 2147483647

Default

Base

service-name

specifies the service name, 64 characters maximum

bgp
Syntax

bgp

Context

show>router

Description

This command enables the context to display BGP-related information.

auth-keychain
Syntax

auth-keychain [keychain]

Context

show>router>bgp

Description

This command displays BGP sessions using a particular authentication keychain.

Parameters
keychain

specifies an existing keychain name

Output

The following output is an example of BGP sessions using an authentication keychain, and BGP Auth-keychain Field Descriptions describes the fields.

Output Example 
*A:ALU-48# show router bgp auth-keychain
===============================================================================
Sessions using key chains
===============================================================================
Peer address             Group               Keychain name
-------------------------------------------------------------------------------
10.20.1.3                1                   eta_keychain1
-------------------------------------------------------------------------------
No. of Peers: 1
===============================================================================
*A:ALU-48#
Table 5. BGP Auth-keychain Field Descriptions

Label

Description

Peer address

The IP address of the peer

Group

The BGP group name

Keychain name

Indicates the authentication keychain associated with the session, if applicable
damping
Syntax

damping [ip-prefix[/ip-prefix-length]] [damp-type] [detail] [ipv4]

damping [ip-prefix[/ip-prefix-length]] [damp-type] [detail] ipv6

damping [ip-prefix[/ip-prefix-length]] [damp-type] [detail] label-ipv4

damping [ip-prefix[/ip-prefix-length]] [damp-type] [detail] label-ipv6

damping [ip-prefix[/ip-prefix-length]] [damp-type] [detail] vpn-ipv4

damping [ip-prefix[/ip-prefix-length]] [damp-type] [detail] vpn-ipv6

damping [ip-prefix[/ip-prefix-length]] [damp-type] [detail] mvpn-ipv4

Context

show>router>bgp

Description

This command displays BGP routes that have been dampened due to route flapping. This command can be entered with or without a route parameter. If no parameters are included, all dampened routes are listed.

If the keyword detail is included, more detailed information is displayed.

If a damp-type is specified, only those types of dampened routes (decayed, history, or suppressed) are displayed. Routes that have a state of decayed have gained penalties for flapping but have not yet reached the suppression limit. Routes that have a state of history have had a route flap and have been withdrawn. Routes that have a state of suppressed have reached the suppression limit and are not considered in BGP path selection.

Parameters
ip-prefix/ip-prefix-length

displays damping information for the specified IP address

Values

ipv4-prefix  a.b.c.d (host bits must be 0)

ipv4-prefix-length  0 to 30

ipv6-prefix  x:x:x:x:x:x:x:x (eight 16-bit  pieces)

 x:x:x:x:x:x:d.d.d.d

 x: [0 to FFFF]H

 d: [0 to 255]D

ipv6-prefix-length  0 to 128

damp-type

displays damping information for routes with the specified damp type

Values

decayed, history, suppressed

detail

displays detailed information

ipv4

displays dampened routes for the IPv4 address family

ipv6

displays dampened routes for the IPv6 address family

label-ipv4

displays dampened routes for the labeled IPv4 address family

label-ipv6

displays dampened routes for the labeled IPv6 address family

vpn-ipv4

displays dampened routes for the VPN-IPv4 address family

vpn-ipv6

displays dampened routes for the VPN-IPv6 address family

mvpn-ipv4

displays dampened routes for the MVPN-IPv4 address family

Output

The following output is an example of BGP damping information, and BGP Damping Field Descriptions describes the fields.

Output Example 
*A: ALU-12>show>router>bgp# damping
===============================================================================
 BGP Router ID:10.0.0.14         AS:65206       Local AS:65206
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best, b - backup
===============================================================================
BGP Damped Routes
===============================================================================
Flag  Network            From            Reuse       AS-Path 
------------------------------------------------------------------------------
ud*i  10.149.7.0/24      10.0.28.1       00h00m00s   60203 65001 19855 3356
                                                      1239  22406 
si    10.155.6.0/23      10.0.28.1       00h43m41s   60203 65001 19855 3356
                                                      2914  7459 
si    10.155.8.0/22      10.0.28.1       00h38m31s   60203 65001 19855 3356
                                                      2914  7459 
si    10.155.12.0/22     10.0.28.1       00h35m41s   60203 65001 19855 3356
                                                      2914  7459 
si    10.155.22.0/23     10.0.28.1       00h35m41s   60203 65001 19855 3356
                                                      2914  7459 
si    10.155.24.0/22     10.0.28.1       00h35m41s   60203 65001 19855 3356
                                                      2914  7459 
si    10.155.28.0/22     10.0.28.1       00h34m31s   60203 65001 19855 3356
                                                      2914  7459 
si    10.155.40.0/21     10.0.28.1       00h28m24s   60203 65001 19855 3356
                                                      7911  7459 
si    10.155.48.0/20     10.0.28.1       00h28m24s   60203 65001 19855 3356
                                                      7911  7459 
ud*i  10.8.140.0/24      10.0.28.1       00h00m00s   60203 65001 19855 3356
                                                      4637  17447 
ud*i  10.8.141.0/24      10.0.28.1       00h00m00s   60203 65001 19855 3356
                                                      4637  17447 
ud*i  10.9.0.0/18        10.0.28.1       00h00m00s   60203 65001 19855 3356
                                                      3561  9658  6163 
. . .
ud*i  10.213.184.0/23    10.0.28.1       00h00m00s   60203 65001 19855 3356
                                                      6774  6774  9154 
------------------------------------------------------------------------------
*A:7705_ALU-2>show>router>bgp#

*A:7705_ALU-2>show>router>bgp# damping detail
==============================================================================
  BGP Router ID : 10.0.0.0         AS : 65206   Local AS : 65206
==============================================================================
  Legend -
  Status codes  : u - used, s - suppressed, h - history, d - decayed, * - 
 valid
  Origin codes  : i - IGP, e - EGP, ? - incomplete,  - best
==============================================================================
BGP Damped Routes
==============================================================================
------------------------------------------------------------------------------
Network : 10.149.7.0/24
------------------------------------------------------------------------------
Network          : 10.149.7.0/24        Peer             : 10.0.28.1
NextHop          : 10.0.28.1            Reuse time       : 00h00m00s
Peer AS          : 60203                Peer Router-Id   : 10.10.10.203
Local Pref       : none
Age              : 00h22m09s            Last update      : 02d00h58m
FOM Present      : 738                  FOM Last upd.    : 2039
Number of Flaps  : 2                    Flags            : ud*i
Path             : 60203 65001 19855 3356  1239  22406
Applied Policy   : default-damping-profile
------------------------------------------------------------------------------
Network : 10.142.48.0/20
------------------------------------------------------------------------------
Network          : 10.142.48.0/20       Peer             : 10.0.28.1
NextHop          : 10.0.28.1            Reuse time       : 00h00m00s
Peer AS          : 60203                Peer Router-Id   : 10.10.10.203
Local Pref       : none
Age              : 00h00m38s            Last update      : 02d01h20m
FOM Present      : 2011                 FOM Last upd.    : 2023
Number of Flaps  : 2                    Flags            : ud*i
Path             : 60203 65001 19855 3356  3561  5551  1889
Applied Policy   : default-damping-profile
------------------------------------------------------------------------------
Network : 10.200.128.0/19
------------------------------------------------------------------------------
Network          : 10.200.128.0/19      Peer             : 10.0.28.1
NextHop          : 10.0.28.1            Reuse time       : 00h00m00s
Peer AS          : 60203                Peer Router-Id   : 10.10.10.203
Local Pref       : none
Age              : 00h00m38s            Last update      : 02d01h20m
FOM Present      : 2011                 FOM Last upd.    : 2023
Number of Flaps  : 2                    Flags            : ud*i
Path             : 60203 65001 19855 1299  702   1889
Applied Policy   : default-damping-profile
------------------------------------------------------------------------------
Network : 10.203.192.0/18
-------------------------------------------------------------------------------
Network          : 10.203.192.0/18      Peer             : 10.0.28.1
NextHop          : 10.0.28.1            Reuse time       : 00h00m00s
Peer AS          : 60203                Peer Router-Id   : 10.10.10.203
Local Pref       : none
Age              : 00h00m07s            Last update      : 02d01h20m
FOM Present      : 1018                 FOM Last upd.    : 1024
Number of Flaps  : 1                    Flags            : ud*i
Path             : 60203 65001 19855 1299  702   1889
Applied Policy   : default-damping-profile
------------------------------------------------------------------------------
*A:7705_ALU-2>show>router>bgp#

*A:7705_ALU-2>show>rouetr>bgp# damping 10.203.192.0/18 detail
==============================================================================
  BGP Router ID : 10.0.0.14         AS : 65206   Local AS : 65206
==============================================================================
  Legend -
  Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
  Origin codes  : i - IGP, e - EGP, ? - incomplete,  - best
==============================================================================
BGP Damped Routes 10.203.192.0/18
==============================================================================
Network : 10.203.192.0/18
------------------------------------------------------------------------------
Network          : 10.203.192.0/18      Peer             : 10.0.28.1
NextHop          : 10.0.28.1            Reuse time       : 00h00m00s
Peer AS          : 60203                Peer Router-Id   : 10.10.10.203
Local Pref       : none
Age              : 00h00m42s            Last update      : 02d01h20m
FOM Present      : 2003                 FOM Last upd.    : 2025
Number of Flaps  : 2                    Flags            : ud*i
Path             : 60203 65001 19855 3356  702   1889
Applied Policy   : default-damping-profile
------------------------------------------------------------------------------
Paths : 1
==============================================================================
*A:7705_ALU-2>show>router>bgp#

*A:7705_ALU-2>show>router>bgp# damping suppressed detail
==============================================================================
  BGP Router ID : 10.0.0.14         AS : 65206   Local AS : 65206
==============================================================================
  Legend -
  Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
  Origin codes  : i - IGP, e - EGP, ? - incomplete,  - best
==============================================================================
BGP Damped Routes (Suppressed)
==============================================================================
Network : 10.142.48.0/20
------------------------------------------------------------------------------
Network          : 10.142.48.0/20       Peer             : 10.0.28.1
NextHop          : 10.0.28.1            Reuse time       : 00h29m22s
Peer AS          : 60203                Peer Router-Id   : 10.10.10.203
Local Pref       : none
Age              : 00h01m28s            Last update      : 02d01h20m
FOM Present      : 2936                 FOM Last upd.    : 3001
Number of Flaps  : 3                    Flags            : si
Path             : 60203 65001 19855 3356  702   1889
Applied Policy   : default-damping-profile
------------------------------------------------------------------------------
Network : 10.200.128.0/19
------------------------------------------------------------------------------
Network          : 10.200.128.0/19      Peer             : 10.0.28.1
NextHop          : 10.0.28.1            Reuse time       : 00h29m22s
Peer AS          : 60203                Peer Router-Id   : 10.10.10.203
Local Pref       : none
Age              : 00h01m28s            Last update      : 02d01h20m
FOM Present      : 2936                 FOM Last upd.    : 3001
Number of Flaps  : 3                    Flags            : si
Path             : 60203 65001 19855 3356  702   1889
Applied Policy   : default-damping-profile
------------------------------------------------------------------------------
Network : 10.203.240.0/20
------------------------------------------------------------------------------
Network          : 10.203.240.0/20      Peer             : 10.0.28.1
NextHop          : 10.0.28.1            Reuse time       : 00h29m22s
Peer AS          : 60203                Peer Router-Id   : 10.10.10.203
Local Pref       : none
Age              : 00h01m28s            Last update      : 02d01h20m
FOM Present      : 2936                 FOM Last upd.    : 3001
Number of Flaps  : 3                    Flags            : si
Path             : 60203 65001 19855 3356  702   1889
Applied Policy   : default-damping-profile
------------------------------------------------------------------------------
Network : 10.206.0.0/17
------------------------------------------------------------------------------
Network          : 10.206.0.0/17        Peer             : 10.0.28.1
NextHop          : 10.0.28.1            Reuse time       : 00h29m22s
Peer AS          : 60203                Peer Router-Id   : 10.10.10.203
Local Pref       : none
Age              : 00h01m28s            Last update      : 02d01h20m
FOM Present      : 2936                 FOM Last upd.    : 3001
Number of Flaps  : 3                    Flags            : si
Path             : 60203 65001 19855 3356  702   1889
Applied Policy   : default-damping-profile
------------------------------------------------------------------------------
*A:7705_ALU-2>show>router>bgp#
Table 6. BGP Damping Field Descriptions

Label

Description

BGP Router ID

The local BGP router ID

AS

The configured autonomous system number

Local AS

The configured or inherited local AS for the specified peer group; if not configured, it is the same value as the AS

Network

The IP prefix and mask length for the route

Flag/Flags

Legend:

Status codes: u-used, s-suppressed, h-history, d-decayed, *-valid (if an * is not present, the status is invalid)

Origin codes: i-IGP, e-EGP, ?-incomplete, >-best

From

The originator ID path attribute value

Reuse/Reuse time

The time when a suppressed route can be used again

AS-Path

The BGP AS path for the route

Peer

The router ID of the advertising router

NextHop

The BGP next hop for the route

Peer AS

The autonomous system number of the advertising router

Peer Router-Id

The router ID of the advertising router

Local Pref

The BGP local preference path attribute for the route

Age

The time elapsed since the service was enabled

Last update

The time that BGP was last updated

FOM Present

The current Figure of Merit (FOM) value

FOM Last upd.

The last updated FOM value

Number of Flaps

The number of flaps in the neighbor connection

Reuse time

The time when the route can be reused

Path

The BGP AS path for the route

Applied Policy

The applied route policy name
group
Syntax

group [name] [detail]

Context

show>router>bgp

Description

This command displays group information for a BGP peer group. This command can be entered with or without parameters.

When this command is entered without a group name, information about all peer groups displays.

When the command is issued with a specific group name, information only pertaining to that specific peer group displays.

The ‟State” field displays the BGP group’s operational state. Valid states are:

  • Up — BGP global process is configured and running

  • Down — BGP global process is administratively shut down and not running

  • Disabled — BGP global process is operationally disabled. The process must be restarted by the operator.

Parameters
name

displays information for the specified BGP group

detail

displays detailed information

Output

The following output is an example of BGP group information, and BGP Group Field Descriptions describes the fields.

Output Example 
*A:7705_ALU-2>show>router>bgp# group
===============================================================================
BGP Group
===============================================================================
-------------------------------------------------------------------------------
Group            : bgp_group
-------------------------------------------------------------------------------
Group Type       : No Type              State            : Up
Peer AS          : n/a                  Local AS         : 1
Local Address    : n/a                  Loop Detect      : Ignore
Import Policy    : None Specified / Inherited
Export Policy    : None Specified / Inherited
Hold Time        : 90                   Keep Alive       : 30
Min Hold Time    : 10                   
Cluster Id       : None                 Client Reflect   : Enabled
NLRI             : Unicast              Preference       : 170
TTL Security     : Enabled              Min TTL Value    : 10
Graceful Restart : Enabled              Stale Routes Time: 360
Auth key chain   : n/a
Bfd Enabled      : Disabled
Creation Origin  : manual

Split Horizon    : Disabled

List of Static Peers
- 10.44.44.44 :

List of Dynamic Peers
- 10.100.1.3
- 3ffe::a14:103

Total Peers      : 3                    Established      : 2
-------------------------------------------------------------------------------
Peer Groups : 1

*A:7705_ALU-2>show>router>bgp# group detail
===============================================================================
BGP Group  (detail)
===============================================================================
-------------------------------------------------------------------------------
Group            : bgp_group
-------------------------------------------------------------------------------
Group Type       : No Type              State            : Up
Peer AS          : n/a                  Local AS         : 1
Local Address    : n/a                  Loop Detect      : Ignore
Connect Retry    : 120                  Authentication   : None
Local Pref       : 100                  MED Out          : 0
Multihop         : 0 (Default)          AS Override      : Disabled
Min Route Advt.  : 30                   Min AS Originate : 15
Prefix_Limit     : No Limit
Passive          : Disabled
Next Hop Self    : Disabled             Aggregator ID 0  : Disabled
Remove Private   : Disabled             Damping          : Enabled
Import Policy    : None Specified / Inherited
Export Policy    : None Specified / Inherited
Hold Time        : 90                   Keep Alive       : 30
Min Hold Time    : 10                   
Cluster Id       : None                 Client Reflect   : Enabled
NLRI             : Unicast              Preference       : 170
TTL Security     : Enabled              Min TTL Value    : 10
Graceful Restart : Enabled              Stale Routes Time: 360
Auth key chain   : n/a
Bfd Enabled      : Disabled
Creation Origin  : manual
Split Horizon    : Disabled

List of Static Peers
- 10.44.44.44 :

List of Dynamic Peers
- 10.100.1.3
- 3ffe::a14:103

Total Peers      : 3                    Established      : 2

===============================================================================
Prefix Limits Per Address Family
===============================================================================
Family         Limit          Idle Timeout   Threshold Log Only  Post Import
-------------------------------------------------------------------------------
No prefix-limit entries configured
===============================================================================
-------------------------------------------------------------------------------
Peer Groups : 1
===============================================================================
*A:7705_ALU-2>show>router>bgp#
Table 7. BGP Group Field Descriptions

Label

Description

Group

The BGP group name

Group Type

No Type: peer type not configured

External: peer type configured as external BGP peers

Internal: peer type configured as internal BGP peers

State

Disabled: the BGP peer group has been operationally disabled

Down: the BGP peer group is operationally inactive

Up: the BGP peer group is operationally active

Peer AS

The configured or inherited peer AS for the specified peer group

Local AS

The configured or inherited local AS for the specified peer group

Local Address

The configured or inherited local address for originating peering for the specified peer group

Loop Detect

The configured or inherited loop detect setting for the specified peer group

Connect Retry

The configured or inherited connect retry timer value

Authentication

None: no authentication is configured

MD5: MD5 authentication is configured

Local Pref

The configured or inherited local preference value

MED Out

The configured or inherited MED value that is assigned to advertised routes

Multihop

The maximum number of router hops a BGP connection can traverse

AS Override

The setting of the AS override

Min Route Advt.

The minimum amount of time that must pass between route updates for the same IP prefix

Min AS Originate

The minimum amount of time that must pass between updates for a route originated by the local router

Prefix Limit

No Limit: no route limit assigned to the BGP peer group

1 — 4294967295: the maximum number of routes BGP can learn from a peer

Passive

Disabled: BGP attempts to establish a BGP connection with a neighbor in the specified peer group

Enabled: BGP will not actively attempt to establish a BGP connection with a neighbor in the specified peer group

Next Hop Self

Disabled: BGP is not configured to send only its own IP address as the BGP next hop in route updates to neighbors in the peer group

Enabled: BGP sends only its own IP address as the BGP next hop in route updates to neighbors in the specified peer group

Aggregator ID 0

Disabled: BGP is not configured to set the aggregator ID to 0.0.0.0 in all originated route aggregates sent to the neighbor in the peer group

Enabled: BGP is configured to set the aggregator ID to 0.0.0.0 in all originated route aggregates sent to the neighbor in the peer group

Remove Private

Disabled: BGP will not remove all private AS numbers from the AS path attribute in updates sent to the neighbor in the peer group

Enabled: BGP removes all private AS numbers from the AS path attribute in updates sent to the neighbor in the peer group

Damping

Disabled: the peer group is configured not to dampen route flaps

Enabled: the peer group is configured to dampen route flaps

Import Policy

The configured import policies for the peer group

Export Policy

The configured export policies for the peer group

Hold Time

The configured hold-time setting

Keep Alive

The configured keepalive setting

Min Hold Time

The configured minimum hold-time setting

Cluster Id

The configured route reflector cluster ID

None: No cluster ID has been configured

Client Reflect

Disabled: the BGP route reflector will not reflect routes to this neighbor

Enabled: the BGP route reflector is configured to reflect routes to this neighbor

NLRI

The type of network layer reachability information that the specified peer group can accept

Unicast: IPv4 unicast routing information can be carried

Preference

The configured route preference value for the peer group

TTL Security

Enabled: TTL security is enabled

Disabled: TTL security is disabled

Min TTL Value

The minimum TTL value configured for the peer

Graceful Restart

The state of graceful restart

Stale Routes Time

The length of time that stale routes are kept in the route table

Auth key chain

The value for the authentication key chain

Bfd Enabled

Enabled: BFD is enabled

Disabled: BFD is disabled

Creation Origin

The creation method of the peer group

Split Horizon

The configured split-horizon setting

List of Static Peers

The list of BGP static peers configured under the peer group

List of Dynamic Peers

The list of BGP dynamic peers learned under the peer group

Total Peers

The total number of peers configured or learned under the peer group

Established

The total number of peers that are in an established state

Prefix Limits Per Address Family

Family

The IP family

Limit

The maximum number of routes BGP can learn from the address family. ‟No Limit” means that a limit has not been assigned.

Idle Timeout

The duration, in minutes, before automatically re-establishing a session if it was taken down when the prefix limit was reached

Threshold Log Only

Indicates that a warning message is sent at the specified threshold percentage and also when the prefix limit is reached. The BGP session is not taken down.

Post Import

Indicates that the prefix limit is applied only to the routes that are accepted by import policies

Peer Groups

The number of peer groups
inter-as-label
Syntax

inter-as-label

Context

show>router>bgp

Description

This command displays a summary of BGP inter-autonomous system (inter-AS) service label information pertaining to a next-hop resolution when enable-rr-vpn-forwarding is enabled.

Output

The following output is an example of inter-AS service label information, and Inter-AS Service Label Field Descriptions describes the fields.

Output Example 
*A:7705_ALU-2>show>router>bgp# inter-as-labels

===============================================================================
BGP Inter-AS labels
===============================================================================
NextHop                       Received       Advertised     Label              
                              Label          Label          Origin             
-------------------------------------------------------------------------------
10.20.1.1                     131069         131057         Internal           
10.20.1.1                     131070         131055         Internal           
10.20.1.1                     131071         131056         Internal           
10.20.1.2                     131068         131050         Internal           
10.20.1.2                     131070         131053         Internal           
10.20.1.6                     131066         131049         Internal           
10.20.1.6                     131067         131052         Internal           
10.20.1.6                     131070         131051         Internal           
-------------------------------------------------------------------------------
Total Labels allocated:   9
===============================================================================
Table 8. Inter-AS Service Label Field Descriptions

Label

Description

NextHop

The BGP next hop ID

Received Label

The service label ID that is received by the Multiprotocol Border Gateway Protocol (MP-BGP)

Advertised Label

The service label ID that is advertised by the MP-BGP

Label Origin

The origin of the received label (either external or internal)

Total Labels allocated

The total number of service labels that are allocated as a result of the next-hop resolution
neighbor
Syntax

neighbor [ip-address [detail]]

neighbor [as-number [detail]]

neighbor ip-address [family [type mvpn-type]] filter1 [brief]

neighbor ip-address [family] filter2

neighbor as-number [family] filter2

neighbor ip-address orf [filter3]

neighbor ip-address graceful-restart

neighbor [dynamic]

Context

show>router>bgp

Description

This command displays BGP neighbor information. This command can be entered with or without any parameters.

When this command is issued without any parameters, information about all BGP peers displays.

When the command is issued with a specific IP address or ASN, information regarding only that specific peer or peers with the same AS displays.

Note: This information is not available when using SNMP.
Parameters
ip-address

the specified IP address for which to display information

Values

ipv4-address:  a.b.c.d

ipv6-address:  x:x:x:x:x:x:x:x[-interface]

 x:x:x:x:x:x:d.d.d.d[-interface]

 x: [0 to FFFF]H

 d: [0 to 255]D

interface: 32 characters maximum,  mandatory for link local addresses

detail

displays detailed information

as-number

the specified AS number for which to display information

Values

1 to 4294967295

family

displays only those BGP peers that have the specified address family enabled

Values

ipv4 | vpn-ipv4 | ipv6 | vpn-ipv6 | mvpn-ipv4 | route-target | evpn | label-ipv4 | label-ipv6 | bgp-ls

type

displays information for the MVPN type

mvpn-type

the specified MVPN type for which to display information

Values

intra-ad | inter-ad | spmsi-ad | leaf-ad | source-ad | shared-join | source-join

filter1

displays information for the specified IP address

Values

received-routes — displays the number of routes received from this peer

advertised-routes — displays the number of routes advertised by this peer

filter2

displays information for the specified AS number

Values

history — displays statistics for dampened routes

suppressed — displays the number of paths from this peer that have been suppressed by damping

Note: When either received-routes or advertised-routes is specified, the routes that are received from or sent to the specified peer are listed. When either history or suppressed is specified, the routes that are learned from those peers that either have a history or are suppressed are listed.
brief

displays information in a brief format. This parameter is only supported with received-routes and advertised-routes.

orf

displays outbound route filtering for the BGP instance. ORF (Outbound Route Filtering) is used to inform a neighbor of targets (using target-list) that it is willing to receive. This mechanism helps lessen the update exchanges between neighbors and saves CPU cycles to process routes that could have been received from the neighbor only to be dropped/ignored.

filter3

displays path information for the specified IP address

Values

send — displays the number of paths sent to this peer

receive — displays the number of paths received from this peer

graceful-restart

displays neighbors configured for graceful restart

dynamic

displays information for dynamic BGP neighbors

Output

The following outputs are examples of BGP neighbor information:

Output Example - BGP Neighbor (standard, detailed, and dynamic) 
*A:7705_ALU-2>show>router>bgp# neighbor
===============================================================================
BGP Neighbor
===============================================================================
-------------------------------------------------------------------------------
Peer  : 10.10.10.12
Group : ibgp_group
-------------------------------------------------------------------------------
Peer AS              : 65000            Peer Port            : 49550
Peer Address         : 10.10.10.12
Local AS             : 65000            Local Port           : 179
Local Address        : 10.10.10.1
Peer Type            : Internal         Dynamic Peer         : No
State                : Established      Last State           : Established
Last Event           : recvKeepAlive
Last Error           : Cease
Local Family         : IPv4 VPN-IPv4
Remote Family        : IPv4 VPN-IPv4
Hold Time            : 90               Keep Alive           : 30
Min Hold Time        : 10                   
Active Hold Time     : 90               Active Keep Alive    : 30
Cluster Id           : None
Preference           : 170              Num of Flaps         : 0
Recd. Paths          : 19
IPv4 Recd. Prefixes  : 600              IPv4 Active Prefixes : 563
IPv4 Suppressed Pfxs : 0                VPN-IPv4 Suppr. Pfxs : 0
VPN-IPv4 Recd. Pfxs  : 8656             VPN-IPv4 Active Pfxs : 8656
IPv6 Recd. Prefixes  : 0                IPv6 Active Prefixes : 0
VPN-IPv6 Recd. Pfxs  : 0                VPN-IPv6 Active Pfxs : 0
VPN-IPv6 Suppr. Pfxs : 0

Backup IPv4 Pfxs     : 0                Backup IPv6 Pfxs     : 0

Backup Vpn IPv4 Pfxs : 0                Backup Vpn IPv6 Pfxs : 0
Input Queue          : 0                Output Queue         : 0
i/p Messages         : 1141             o/p Messages         : 1041
i/p Octets           : 449029           o/p Octets           : 163814
i/p Updates          : 151              o/p Updates          : 50
TTL Security         : Enabled          Min TTL Value        : 10
Graceful Restart     : Disabled         Stale Routes Time    : n/a
Advertise Inactive   : Disabled         Peer Tracking        : Disabled
Advertise Label      : None
Auth key chain       : n/a
Disable Cap Nego     : Disabled         Bfd Enabled          : Disabled
Local Capability     : RouteRefresh MP-BGP
Remote Capability    : RouteRefresh MP-BGP
Local AddPath Capabi*: Disabled
Remote AddPath Capab*: Send - None
                     : Receive - None
Import Policy        : None Specified / Inherited
Export Policy        : stmt1
-------------------------------------------------------------------------------
Neighbors : 1
===============================================================================
*A:7705_ALU-2>show>router>bgp#

*A:7705_ALU-2>show>router>bgp# neighbor 10.10.10.12 detail
===============================================================================
BGP Neighbor
===============================================================================
-------------------------------------------------------------------------------
Peer  : 10.10.10.12
Group : iBGP
-------------------------------------------------------------------------------
Peer AS              : 65000            Peer Port            : 49550
Peer Address         : 10.10.10.12
Local AS             : 65000            Local Port           : 179
Local Address        : 10.10.10.1
Peer Type            : Internal         Dynamic Peer         : No
State                : Established      Last State           : Established
Last Event           : recvKeepAlive
Last Error           : Cease
Local Family         : IPv4 VPN-IPv4
Remote Family        : IPv4 VPN-IPv4
Connect Retry        : 120              Local Pref.          : 70
Min Route Advt.      : 30               Min AS Orig.         : 15
Multihop             : 0 (Default)      AS Override          : Disabled
Damping              : Disabled         Loop Detect          : Ignore
MED Out              : No MED Out       Authentication       : None
Next Hop Self        : Disabled         AggregatorID Zero    : Disabled
Remove Private       : Disabled         Passive              : Disabled
Peer Identifier      : 10.10.10.12      Fsm Est. Trans       : 1
Fsm Est. Time        : 22h42m46s        InUpd Elap. Time     : 22h54m31s
Prefix Limit         : No Limit         Pref Limit Idle Time*: forever
Hold Time            : 90               Keep Alive           : 30
Min Hold Time        : 10                   
Active Hold Time     : 90               Active Keep Alive    : 30
Cluster Id           : None             Client Reflect       : Disabled
Preference           : 170              Num of Flaps         : 0
Recd. Paths          : 19
IPv4 Recd. Prefixes  : 600              IPv4 Active Prefixes : 563
IPv4 Suppressed Pfxs : 0                VPN-IPv4 Suppr. Pfxs : 0
VPN-IPv4 Recd. Pfxs  : 8656             VPN-IPv4 Active Pfxs : 8656
                                        IPv6 Suppressed Pfxs : 0
IPv6 Recd. Prefixes  : 0                IPv6 Active Prefixes : 0
VPN-IPv6 Recd. Pfxs  : 0                VPN-IPv6 Active Pfxs : 0
VPN-IPv6 Suppr. Pfxs : 0
Backup IPv4 Pfxs     : 0                Backup IPv6 Pfxs     : 0
Backup Vpn IPv4 Pfxs : 0                Backup Vpn IPv6 Pfxs : 0
Input Queue          : 0                Output Queue         : 0
i/p Messages         : 2881             o/p Messages         : 2777
i/p Octets           : 482089           o/p Octets           : 196798
i/p Updates          : 151              o/p Updates          : 50
TTL Security         : Enabled          Min TTL Value        : 10
Graceful Restart     : Disabled         Stale Routes Time    : n/a
Advertise Inactive   : Disabled         Peer Tracking        : Disabled
Advertise Label      : None
Auth key chain       : n/a
Bfd Enabled          : Enabled
Disable Cap Nego     : Disabled         Bfd Enabled          : Disabled
Local Capability     : RtRefresh MPBGP 4byte ASN
Remote Capability    :
Local AddPath Capabi*: Disabled
Remote AddPath Capab*: Send - None
                     : Receive - None
Import Policy        : None Specified / Inherited
Export Policy        : stmt1
-------------------------------------------------------------------------------
Neighbors : 1
===============================================================================
*A:7705_ALU-2>show>router>bgp# 

*A:7705_ALU-2>show>router>bgp# neighbor 10.0.0.11 orf
===============================================================================
BGP Neighbor 10.0.0.11 ORF
===============================================================================
Send List (Automatic)
-------------------------------------------------------------------------------
target:65535:10
target:65535:20
===============================================================================
*A:7705_ALU-2>show>router>bgp# 

*A:7705_ALU-2>show>router>bgp# neighbor 10.0.0.1 orf
===============================================================================
BGP Neighbor 10.0.0.1 ORF
===============================================================================
Receive List
-------------------------------------------------------------------------------
target:65535:10
target:65535:20
===============================================================================
*A:7705_ALU-2>show>router>bgp# 

*A:7705_ALU-2>show>router>bgp# neighbor dynamic
===============================================================================
BGP Neighbor
===============================================================================
-------------------------------------------------------------------------------
Peer                 : 10.100.1.3
Description          : (Not Specified)
Group                : dynamic
-------------------------------------------------------------------------------
Peer AS              : 65000            Peer Port            : 51374
Peer Address         : 10.100.1.3
Local AS             : 65000            Local Port           : 179  
Local Address        : 10.100.1.2
Peer Type            : Internal         Dynamic Peer         : Yes
State                : Established      Last State           : Established
Last Event           : recvKeepAlive
Last Error           : Cease (Connection Collision Resolution)
Local Family         : IPv4 VPN-IPv4 IPv6 VPN-IPv6
Remote Family        : IPv4 VPN-IPv4 IPv6 VPN-IPv6
Hold Time            : 90               Keep Alive           : 30   
Min Hold Time        : 0                
Active Hold Time     : 90               Active Keep Alive    : 30   
Cluster Id           : None             
Preference           : 170              Num of Update Flaps  : 0    
Recd. Paths          : 6                
IPv4 Recd. Prefixes  : 5                IPv4 Active Prefixes : 0    
IPv4 Suppressed Pfxs : 0                VPN-IPv4 Suppr. Pfxs : 0    
VPN-IPv4 Recd. Pfxs  : 0                VPN-IPv4 Active Pfxs : 0    
IPv6 Suppressed Pfxs : 0    
IPv6 Recd. Prefixes  : 2                IPv6 Active Prefixes : 0    
VPN-IPv6 Recd. Pfxs  : 0                VPN-IPv6 Active Pfxs : 0    
VPN-IPv6 Suppr. Pfxs : 0                
MVPN-IPv4 Suppr. Pfxs: 0                MVPN-IPv4 Recd. Pfxs : 0    
MVPN-IPv4 Active Pfxs: 0                
Flow-IPv4 Suppr. Pfxs: N/A              Flow-IPv4 Recd. Pfxs : N/A    
Flow-IPv4 Active Pfxs: N/A              Rte-Tgt Suppr. Pfxs  : 0    
Rte-Tgt Recd. Pfxs   : 0                Rte-Tgt Active Pfxs  : 0    
Backup IPv4 Pfxs     : 0                Backup IPv6 Pfxs     : 0    
Mc Vpn Ipv4 Suppr. P*: N/A               
Backup Vpn IPv4 Pfxs : 0                Backup Vpn IPv6 Pfxs : 0    
Input Queue          : 0                Output Queue         : 0    
i/p Messages         : 11               o/p Messages         : 9    
i/p Octets           : 951              o/p Octets           : 445
i/p Updates          : 6                o/p Updates          : 4    
Evpn Suppr. Pfxs     : 0                Evpn Recd. Pfxs      : 0    
Evpn Active Pfxs     : 0                
MS-PW Suppr. Pfxs    : N/A              MS-PW Recd. Pfxs     : N/A   
MS-PW Active Pfxs    : N/A               
TTL Security         : Disabled         Min TTL Value        : n/a
Graceful Restart     : Disabled         Stale Routes Time    : n/a
Advertise Inactive   : Disabled         Peer Tracking        : Disabled
Auth key chain       : n/a
Disable Cap Nego     : N/A              Bfd Enabled          : Disabled
Flowspec Validate    : N/A              Default Route Tgt    : Disabled
Aigp Metric          : Disabled         Split Horizon        : Enabled
Local Capability     : RtRefresh MPBGP 4byte ASN 
Remote Capability    : RtRefresh MPBGP 4byte ASN 
Local AddPath Capabi*: Disabled
Remote AddPath Capab*: Send - None
                     : Receive - None
Import Policy        : None Specified / Inherited
Export Policy        : expPol
Origin Validation    : N/A
EBGP Link Bandwidth  : n/a
IPv4 Rej. Pfxs       : 0                IPv6 Rej. Pfxs       : 0    
VPN-IPv4 Rej. Pfxs   : 0                VPN-IPv6 Rej. Pfxs   : 0    
Mc IPv4 Rej. Pfxs    : 0                Mc IPv6 Rej. Pfxs    : 0    
MVPN-IPv4 Rej. Pfxs  : 0                MVPN-IPv6 Rej. Pfxs  : 0    
Flow-IPv4 Rej. Pfxs  : 0                Flow-IPv6 Rej. Pfxs  : 0  
L2-VPN Rej. Pfxs     : 0                MDT-SAFI Rej. Pfxs   : 0    
Rte-Tgt Rej. Pfxs    : 0                MS-PW Rej. Pfxs      : 0    
Mc Vpn Ipv4 Rej. Pfxs: 0                Evpn Rej. Pfxs       : 0    
Label-v4 Suppr. Pfxs : 0                Label-v4 Recd. Pfxs  : 0    
Label-v4 Active Pfxs : 0                Label-v4 Rej. Pfxs   : 0    
Label-v6 Suppr. Pfxs : 0                Label-v6 Recd. Pfxs  : 0    
Label-v6 Active Pfxs : 0                Label-v6 Rej. Pfxs   : 0    
Bgp-Ls Suppr. Pfxs   : 0                Bgp-Ls Recd. Pfxs    : 0    
Bgp-Ls Active Pfxs   : 0                Bgp-Ls Rej. Pfxs     : 0    
-------------------------------------------------------------------------------
Table 9. BGP Neighbor (Standard, Detailed, and Dynamic) Field Descriptions

Label

Description

Peer

The IP address of the configured BGP peer

Group

The BGP peer group to which this peer is assigned

Peer AS

The configured or inherited peer AS for the peer group

Peer Address

The configured address for the BGP peer

Peer Port

The TCP port number used on the far-end system

Local AS

The configured or inherited local AS for the peer group

Local Address

The configured or inherited local address for originating peering for the peer group

Local Port

The TCP port number used on the local system

Peer Type

External: peer type configured as external BGP peers

Internal: peer type configured as internal BGP peers

Dynamic Peer

Yes: the session is dynamic (that is, unconfigured)

No: the session is statically configured

State

Idle: The BGP peer is not accepting connections. (Shutdown) is also displayed if the peer is administratively disabled.

Active: BGP is listening for and accepting TCP connections from this peer

Connect: BGP is attempting to establish a TCP connection with this peer

Open Sent: BGP has sent an OPEN message to the peer and is waiting for an OPEN message from the peer

Open Confirm: BGP has received a valid OPEN message from the peer and is awaiting a KEEPALIVE or NOTIFICATION

Established: BGP has successfully established a peering session and is exchanging routing information

Last State

Idle: The BGP peer is not accepting connections

Active: BGP is listening for and accepting TCP connections from this peer

Connect: BGP is attempting to establish a TCP connections with this peer

Open Sent: BGP has sent an OPEN message to the peer and is waiting for an OPEN message from the peer

Open Confirm: BGP has received a valid OPEN message from the peer and is awaiting a KEEPALIVE or NOTIFICATION

Last Event

start: BGP has initialized the BGP neighbor

stop: BGP has disabled the BGP neighbor

open: BGP transport connection is opened

close: BGP transport connection is closed

openFail: BGP transport connection failed to open

error: BGP transport connection error

connectRetry: the connect retry timer expired

holdTime: the hold time timer expired

keepAlive: the keepalive timer expired

recvOpen: BGP has received an OPEN message

revKeepalive: BGP has received a KEEPALIVE message

recvUpdate: BGP has received an UPDATE message

recvNotify: BGP has received a NOTIFICATION message

None: no events have occurred

Last Error

The last BGP error and subcode to occur on the BGP neighbor

Local Family

The configured local family value

Remote Family

The configured remote family value

Connect Retry

The configured or inherited connect retry timer value

Local Pref.

The configured or inherited local preference value

Min Route Advt.

The minimum amount of time that must pass between route updates for the same IP prefix

Min AS Originate

The minimum amount of time that must pass between updates for a route originated by the local router

Multihop

The maximum number of router hops a BGP connection can traverse

Damping

Disabled: the BGP neighbor is configured not to dampen route flaps

Enabled: the BGP neighbor is configured to dampen route flaps

Loop Detect

Ignore: The BGP neighbor is configured to ignore routes with an AS loop

Drop: The BGP neighbor is configured to drop the BGP peering if an AS loop is detected

Off: AS loop detection is disabled for the neighbor

MED Out

The configured or inherited MED value that is assigned to advertised routes

Authentication

None: no authentication is configured

MD5: MD5 authentication is configured

Next Hop Self

Disabled: BGP is not configured to send only its own IP address as the BGP next hop in route updates to the specified neighbor

Enabled: BGP will send only its own IP address as the BGP next hop in route updates to the neighbor

AggregatorID Zero

Disabled: the BGP neighbor is not configured to set the aggregator ID to 0.0.0.0 in all originated route aggregates

Enabled: the BGP neighbor is configured to set the aggregator ID to 0.0.0.0 in all originated route aggregates

Remove Private

Disabled: BGP will not remove all private AS numbers from the AS path attribute in updates sent to the specified neighbor

Enabled: BGP will remove all private AS numbers from the AS path attribute in updates sent to the specified neighbor

Passive

Disabled: BGP will actively attempt to establish a BGP connection with the specified neighbor

Enabled: BGP will not actively attempt to establish a BGP connection with the specified neighbor

Peer Identifier

The IP identifier for the peer router

Prefix Limit

No Limit: no route limit assigned to the BGP peer group

1 — 4294967295: the maximum number of routes BGP can learn from a peer

Pref Limit Idle Time*

The length of time that the session is held in the idle state after it is taken down as a result of reaching the prefix limit

Hold Time

The configured hold-time setting

Keep Alive

The configured keepalive setting

Min Hold Time

The configured minimum hold-time setting

Active Hold Time

The negotiated hold time, if the BGP neighbor is in an established state

Active Keep Alive

The negotiated keepalive time, if the BGP neighbor is in an established state

Cluster Id

The configured route reflector cluster ID

None: no cluster ID has been configured

Client Reflect

Disabled: The BGP route reflector is configured not to reflect routes to this neighbor

Enabled: The BGP route reflector is configured to reflect routes to this neighbor

Preference

The configured route preference value for the peer group

Num of Flaps

The number of route flaps in the neighbor connection

Recd. Paths

The number of unique sets of path attributes received from the BGP neighbor

IPv4 Recd. Prefixes

The number of unique sets of IPv4 path attributes received from the BGP neighbor

IPv4 Active Prefixes

The number of IPv4 routes received from the BGP neighbor and active in the forwarding table

IPv4 Suppressed Pfxs

The number of unique sets of IPv4 path attributes received from the BGP neighbor and suppressed due to route damping

VPN-IPv4 Suppr. Pfxs

The number of unique sets of VPN-IPv4 path attributes received from the BGP neighbor and suppressed due to route damping

VPN-IPv4 Recd. Pfxs

The number of unique sets of VPN-IPv4 path attributes received from the BGP neighbor

VPN-IPv4 Active Pfxs

The number of VPN-IPv4 routes received from the BGP neighbor and active in the forwarding table

IPv6 Suppressed. Pfxs

The number of unique sets of IPv6 path attributes received from the BGP neighbor and suppressed due to route damping

IPv6 Recd. Prefixes

The number of unique sets of IPv6 path attributes received from the BGP neighbor

IPv6 Active Prefixes

The number of IPv6 routes received from the BGP neighbor and active in the forwarding table

VPN-IPv6 Recd. Pfxs

The number of unique sets of VPN-IPv6 path attributes received from the BGP neighbor

VPN-IPv6 Active Pfxs

The number of VPN-IPv6 routes received from the BGP neighbor and active in the forwarding table

VPN-IPv6 Suppr. Pfxs

The number of unique sets of VPN-IPv6 path attributes received from the BGP neighbor and suppressed due to route damping

MVPN-IPv4 Suppr. Pfxs

The number of unique sets of MVPN-IPv4 path attributes received from the BGP neighbor and suppressed due to route damping

MVPN-IPv4 Recd. Pfxs

The number of unique sets of MVPN-IPv4 path attributes received from the BGP neighbor

MVPN-IPv4 Active Pfxs

The number of MVPN-IPv4 routes received from the BGP neighbor and active in the forwarding table

Flow-IPv4 Suppr. Pfxs

N/A

Flow-IPv4 Recd. Pfxs

N/A

Flow-IPv4 Active Pfxs

N/A

Rte-Tgt Suppr. Pfxs

The number of unique sets of route target path attributes received from the BGP neighbor and suppressed due to route damping

Rte-Tgt Recd. Pfxs

The number of unique sets of route target path attributes received from the BGP neighbor

Rte-Tgt Active. Pfxs

The number of route target routes received from the BGP neighbor and active in the forwarding table

Backup IPv4 Pfxs

The number of BGP Fast Reroute backup path IPv4 prefixes

Backup IPv6 Pfxs

The number of BGP Fast Reroute backup path IPv6 prefixes

Mc Vpn Ipv4 Suppr. P*

N/A

Backup Vpn IPv4 Pfxs

The number of BGP Fast Reroute backup path VPN IPv4 prefixes

Backup Vpn IPv6 Pfxs

The number of BGP Fast Reroute backup path VPN IPv6 prefixes

Input Queue

The number of BGP messages to be processed

Output Queue

The number of BGP messages to be transmitted

i/p Messages

The total number of packets received from the BGP neighbor

o/p Messages

The total number of packets sent to the BGP neighbor

i/p Octets

The total number of octets received from the BGP neighbor

o/p Octets

The total number of octets sent to the BGP neighbor

i/p Updates

The total number of updates received from the BGP neighbor

o/p Updates

The total number of updates sent to the BGP neighbor

Evpn Suppr. Pfxs

The number of unique sets of EVPN-IPv4 path attributes received from the BGP neighbor and suppressed due to route damping

Evpn Recd. Pfxs

The number of unique sets of EVPN-IPv4 path attributes received from the BGP neighbor

Evpn Active Pfxs

The number of EVPN-IPv4 routes received from the BGP neighbor and active in the forwarding table

MS-PW Suppr. Pfxs

N/A

MS-PW Recd. Pfxs

N/A

MS-PW Active Pfxs

N/A

TTL Security

Enabled: TTL security is enabled

Disabled: TTL security is disabled

Min TTL Value

The minimum TTL value configured for the peer

Graceful Restart

The state of graceful restart

Stale Routes Time

The length of time that stale routes are kept in the route table

Advertise Inactive

The state of advertising inactive BGP routes to other BGP peers (enabled or disabled)

Peer Tracking

The state of tracking a neighbor IP address in the routing table for a BGP session

Advertise Label

Indicates the enabled address family for supporting RFC 3107 BGP label capability

Auth key chain

The value for the authentication key chain

Disable Cap Nego

N/A

Bfd Enabled

Enabled: BFD is enabled

Disabled: BFD is disabled

Flowspec Validate

N/A

Default Route Tgt

Indicates that the default RTC route (zero prefix length) is originated towards the selected peers

Aigp Metric

Indicates whether accumulated IGP (AIGP) path attribute support with one or more BGP peers is enabled or disabled

Split Horizon

Indicates whether split horizon is enabled or disabled, When enabled, split horizon prevents routes from being reflected back to a peer that sends the best route.

Local Capability

The capability of the local BGP speaker; for example, route refresh, MP-BGP, ORF

Remote Capability

The capability of the remote BGP peer; for example, route refresh, MP-BGP, ORF

Local AddPath Capabi*

The state of the local BGP add-paths capabilities. The add-paths capability allows the router to send and receive multiple paths per prefix to or from a peer.

Remote AddPath Capab*

The state of the remote BGP add-paths capabilities

Import Policy

The configured import policies for the peer group

Export Policy

The configured export policies for the peer group

Origin Validation

N/A

EBGP Link Bandwidth

N/A

IPv4 Rej. Pfxs

The number of unique sets of IPv4 path attributes received from the BGP neighbor and rejected by the router

IPv6 Rej. Pfxs

The number of unique sets of IPv6 path attributes received from the BGP neighbor and rejected by the router

VPN-IPv4 Rej. Pfxs

The number of unique sets of VPN-IPv4 path attributes received from the BGP neighbor and rejected by the router

VPN-IPv6 Rej. Pfxs

The number of unique sets of VPN-IPv6 path attributes received from the BGP neighbor and rejected by the router

Mc IPv4 Rej. Pfxs

The number of unique sets of MC IPv4 path attributes received from the BGP neighbor and rejected by the router

Mc IPv6 Rej. Pfxs

The number of unique sets of MC IPv6 path attributes received from the BGP neighbor and rejected by the router

MVPN-IPv4 Rej. Pfxs

The number of unique sets of MVPN-IPv4 path attributes received from the BGP neighbor and rejected by the router

MVPN-IPv6 Rej. Pfxs

The number of unique sets of MVPN-IPv6 path attributes received from the BGP neighbor and rejected by the router

Flow-IPv4 Rej. Pfxs

The number of unique sets of Flow-IPv4 path attributes received from the BGP neighbor and rejected by the router

Flow-IPv6 Rej. Pfxs

The number of unique sets of Flow-IPv6 path attributes received from the BGP neighbor and rejected by the router

L2-VPN Rej. Pfxs

The number of unique sets of L2-VPN path attributes received from the BGP neighbor and rejected by the router

MDT-SAFI Rej. Pfxs

The number of unique sets of MDT-SAFI path attributes received from the BGP neighbor and rejected by the router

Rte-Tgt Rej. Pfxs

The number of unique sets of route target path attributes received from the BGP neighbor and rejected by the router

MS-PW Rej. Pfxs

The number of unique sets of MS-PW path attributes received from the BGP neighbor and rejected by the router

Mc Vpn Ipv4 Rej. Pfxs

The number of unique sets of MC VPN IPv4 path attributes received from the BGP neighbor and rejected by the router

Evpn Rej. Pfxs

The number of unique sets of EVPN path attributes received from the BGP neighbor and rejected by the router

Label-v4 Suppr. Pfxs

The number of unique sets of label-IPv4 path attributes received from the BGP neighbor and suppressed due to route damping

Label-v4 Recd. Pfxs

The number of unique sets of label-IPv4 path attributes received from the BGP neighbor

Label-v4 Active Pfxs

The number of label-IPv4 routes received from the BGP neighbor and active in the forwarding table

Label-v4 Rej. Pfxs

The number of unique sets of label-IPv4 path attributes received from the BGP neighbor and rejected by the router

Label-v6 Suppr. Pfxs

The number of unique sets of label-IPv6 path attributes received from the BGP neighbor and suppressed due to route damping

Label-v6 Recd. Pfxs

The number of unique sets of label-IPv6 path attributes received from the BGP neighbor

Label-v6 Active Pfxs

The number of label-IPv6 routes received from the BGP neighbor and active in the forwarding table

Label-v6 Rej. Pfxs

The number of unique sets of label-IPv6 path attributes received from the BGP neighbor and rejected by the router

Bgp-Ls Suppr. Pfxs

The number of unique sets of BGP LS path attributes received from the BGP neighbor and suppressed due to route damping

Bgp-Ls Recd. Pfxs

The number of unique sets of BGP LS path attributes received from the BGP neighbor

Bgp-Ls Active Pfxs

The number of BGP LS routes received from the BGP neighbor and active in the forwarding table

Bgp-Ls Rej. Pfxs

The number of unique sets of BGP LS path attributes received from the BGP neighbor and rejected by the router

Output Example - BGP Neighbor (advertised-routes and received-routes) 
*A:7705_ALU-2>show>router>bgp# neighbor 10.44.44.44 advertised-routes
===============================================================================
 BGP Router ID : 10.55.55.55       AS : 1       Local AS : 1
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best
===============================================================================
BGP IPv4 Routes
===============================================================================
Flag  Network                                           LocalPref   MED
      Nexthop                                           Path-Id     Label
      As-Path
-------------------------------------------------------------------------------
?     10.0.0.02/32                                      100         none
      10.0.0.16                                         -
      No As-Path
?     10.0.6.04/24                                      100         none 
      10.0.0.16                                         -
      No As-Path
-------------------------------------------------------------------------------
Routes : 2 
===============================================================================
*A:7705_ALU-2>show>router>bgp#

*A:PE1>show>router>bgp# neighbor 10.10.10.12 advertised-routes  brief
===============================================================================
 BGP Router ID : 10.10.10.1        AS : 65000   Local AS : 65000
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best
===============================================================================
BGP IPv4 Routes
===============================================================================
Flag  Network
-------------------------------------------------------------------------------
?     10.10.10.1/32
?     10.10.10.0/24
?     10.10.10.1/24
?     10.10.10.2/24
?     10.10.10.3/24
-------------------------------------------------------------------------------
Routes : 5 
===============================================================================
*A:7705_ALU-2>show>router>bgp#

*A:7705_ALU-2>show>router>bgp# neighbor 10.44.44.44 received-routes
===============================================================================
 BGP Router ID : 10.55.55.55       AS : 1       Local AS : 1
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best
===============================================================================
BGP IPv4 Routes
===============================================================================
Flag  Network                                           LocalPref   MED
      Nexthop                                           Path-Id     Label
      As-Path
-------------------------------------------------------------------------------
?     10.0.0.16/32                                       100         none
      10.0.0.16                                          -
      No As-Path
?     10.0.6.0/24                                        100         none 
      10.0.0.16 -
      No As-Path
?     10.0.8.0/24                                        100         none 
      10.0.0.16                                          -
      No As-Path
?     10.0.12.0/24                                       100         none 
      10.0.0.16                                          -
      No As-Path
-------------------------------------------------------------------------------
Routes : 4 
===============================================================================
*A:7705_ALU-2>show>router>bgp#
Table 10. BGP Neighbor (Advertised-Routes and Received-Routes) Field Descriptions

Label

Description

BGP Router ID

The local BGP router ID

AS

The configured autonomous system number

Local AS

The configured local AS setting. If not configured, then it is the same value as the AS.

Flag/Flags

Legend:

Status codes:

u - used

s - suppressed

h - history

d - decayed

* - valid

If an * is not present, then the status is invalid

Origin codes:

i - IGP

e - EGP

? - incomplete

> - best

Network

The route IP prefix and mask length for the route

Next Hop

The BGP next hop for the route

LocalPref

The BGP local preference path attribute for the route

MED

The BGP Multi-Exit Discriminator (MED) path attribute for the route

Path-Id

The path ID that is received as part of the add-path capability

Label

The BGP label associated with the route

AS-Path

The BGP AS path for the route
Output Example - BGP Neighbor (graceful restart) 
*A:7705_ALU-2>show>router>bgp# neighbor 10.10.120.44 graceful-restart
===============================================================================
BGP Neighbor 10.10.120.44 Graceful Restart
===============================================================================
Graceful Restart locally configured for peer  : Enabled
Peer's Graceful Restart feature               : Enabled
NLRI(s) that peer supports restart for        : IPv4-Unicast IPv4-MPLS IPv4-VPN
NLRI(s) that peer saved forwarding for        : IPv4-Unicast IPv4-MPLS IPv4-VPN
NLRI(s) that restart is negotiated for        : None
NLRI(s) of received end-of-rib markers        : IPv4-Unicast
NLRI(s) of all end-of-rib markers sent        : IPv4-Unicast
Restart time locally configured for peer      : 120 seconds
Restart time requested by the peer            : 390 seconds
Time stale routes from peer are kept for      : 360 seconds
Graceful restart status on the peer           : Not currently being helped
Number of Restarts                            : 328
Last Restart at                               : 08/20/2006 12:22:06
===============================================================================
*A:7705_ALU-2>show>router>bgp#
Table 11. BGP Neighbor (Graceful Restart) Field Descriptions

Label

Description

BGP Neighbor

The IP address of the BGP neighbor

Graceful Restart locally configured for peer

The configured state of graceful restart for the local router

Peer's Graceful Restart feature

The configured state of graceful restart for the peer router

NLRI(s) that peer supports restart for

The families supported by the peer router for graceful restart

NLRI(s) that peer saved forwarding for

The families for which the peer router continued to forward packets after graceful restart

NLRI(s) that restart is negotiated for

The families that negotiate restart during graceful restart

NLRI(s) of received end-of-rib markers

The families for which end-of-RIB markers have been received

NLRI(s) of all end-of-rib markers sent

The families for which end-of-RIB markers have been sent

Restart time locally configured for peer

The length of time configured on the local router for the peer router’s graceful restart

Restart time requested by the peer

The length of time requested by the peer router for graceful restart

Time stale routes from peer are kept for

The length of time that the local router continues to support stale routes

Graceful restart status on the peer

The status of graceful restart on the peer router

Number of Restarts

The number of restarts since graceful restart is enabled between peers

Last Restart at

The local time of the last graceful restart
next-hop
Syntax

next-hop [family [service-id service-id]] [ip-address [detail]]

Context

show>router>bgp

Description

This command displays BGP next-hop information.

Parameters
family

displays only those BGP values that have the specified address family enabled

Values

ipv4 | ipv6 | label-ipv4 | label-ipv6 | vpn-ipv4 | vpn-ipv6 | evpn

service-id

specifies the service ID

Values

1 to 2147483647

ip-address

displays the next hop-information for the specified IP address

Values

ipv4-address:  a.b.c.d

ipv6-address:  x:x:x:x:x:x:x:x[-interface]

 x:x:x:x:x:x:d.d.d.d[-interface]

 x: [0 to FFFF]H

 d: [0 to 255]D

interface: 32 characters maximum,  mandatory for link local addresses

detail

displays the more detailed version of the output

Output

The following output is an example of BGP next-hop information, and BGP Next-Hop Field Descriptions describes the fields.

Output Example 
A:7705_ALU-2>show>router>bgp# next-hop
===============================================================================
 BGP Router ID : 10.10.10.1        AS : 65000   Local AS : 65000
===============================================================================
===============================================================================
BGP Next Hop
===============================================================================
Next Hop                                                    Pref     Owner
   Resolving Prefix                                                  Metric
   Resolved Next Hop                                                 Ref. Count
-------------------------------------------------------------------------------
10.10.10.12                                                     7    ISIS
   10.20.1.1/32                                                      10
   10.10.2.1                                                         592
10.10.10.12                                                     7    ISIS
   10.20.1.2/32                                                      10
   10.10.3.2                                                         592
10.20.1.4                                                       7    ISIS
   10.20.0.0/32                                                      20
   10.10.11.4                                                        8
-------------------------------------------------------------------------------
Next Hops : 3
===============================================================================
A:7705_ALU-2>show>router>bgp# 

A:7705_ALU-2>show>router>bgp# next-hop 10.0.0.1
===============================================================================
 BGP Router ID : 10.10.10.1        AS : 65000   Local AS : 65000
===============================================================================
===============================================================================
BGP Next Hop
===============================================================================
Next Hop                                                        Pref Owner
   Resolving Prefix                                                  Metric
   Resolved Next Hop                                                 Ref. Count
-------------------------------------------------------------------------------
10.0.0.1                                                        15   ISIS
   10.0.0.0/24                                                       20
   10.88.1.2                                                         8
10.0.0.1                                                        15   ISIS
   10.0.0.0/24                                                       20
   10.88.2.2                                                         8
-------------------------------------------------------------------------------
Next Hops : 1
===============================================================================
A:7705_ALU-2>show>router>bgp#

A:7705_ALU-2>show>router>bgp# next-hop 10.0.0.1 detail
===============================================================================
 BGP Router ID : 10.10.10.1        AS : 65000   Local AS : 65000
===============================================================================
===============================================================================
BGP Next Hop
===============================================================================
Next Hop: 10.0.0.1
-------------------------------------------------------------------------------
Resolving Prefix : 10.0.0.0/24
Preference       : 15                   Metric           : 20
Reference Count  : 8                    Owner            : ISIS
Resolved Next Hop: 10.88.1.2
Egress Label     : N/A
Resolved Next Hop: 10.88.2.2
Egress Label     : N/A
Resolved Next Hop: 10.88.3.2
Egress Label     : N/A
-------------------------------------------------------------------------------
Next Hops : 1
===============================================================================
A:7705_ALU-2>show>router>bgp#

The following output displays an example of when the next hop is unresolved by a next-hop-resolution policy.

A:7705_ALU-2>show router bgp next-hop
===============================================================================
 BGP Router ID:10.20.1.3        AS:100         Local AS:100
===============================================================================
===============================================================================
BGP Next Hop
===============================================================================
Next Hop                                                    Pref     Owner
   Resolving Prefix                                         FibProg  Metric
   Resolved Next Hop                                                 Ref. Count
-------------------------------------------------------------------------------
10.20.1.2                                                   10       OSPF
   10.20.1.2/32                                             Y        1000
   10.10.3.2                                                         2
10.20.1.4                                                   10       OSPF
   10.20.1.4/32                                             Y        1000
   10.10.11.4                                                        1
10.20.1.5                                                   -        -
   Unresolved                                                        -
   --                                                                -
-------------------------------------------------------------------------------
Next Hops : 3
===============================================================================
Table 12. BGP Next-Hop Field Descriptions

Label

Description

BGP Router ID

The local BGP router ID

AS

The configured autonomous system number

Local AS

The configured local AS setting. If not configured, then the value is the same as the AS.

Next Hop

The next-hop address

Resolving Prefix

The prefix of the best next hop

Pref: Preference

The BGP preference attribute for the routes

FibProg

Indicates whether a resolved BGP next hop is programmed in the FIB

Metric

The metric derived from the IGP for a particular next hop

Reference Count

The number of routes using the resolving prefix

Owner

The routing protocol used to derive the best next hop

Resolved Next Hop

The IP address of the next hop

Egress Label

The VPN label used for VPN-IPv4 data

Next Hops

The number of next hops
paths
Syntax

paths

Context

show>router>bgp

Description

This command displays a summary of BGP path attributes.

Output

The following output is an example of BGP path information, and BGP Path Field Descriptions describes the fields.

Output Example 
*A:7705_ALU-2>show>router>bgp# paths
===============================================================================
BGP Router ID : 10.55.55.55 AS : 65000   Local AS : 65000
===============================================================================
===============================================================================
BGP Paths
===============================================================================
Path: No As-Path
-------------------------------------------------------------------------------
Next Hop         : 10.44.10.12
Origin           : Incomplete           Segments         : 0
MED              : None                 Local Preference : 4294967295
Refs             : 1080                 ASes             : 0
Flags            : IBGP-learned
-------------------------------------------------------------------------------
Path: No As-Path
-------------------------------------------------------------------------------
Next Hop         : 10.88.1.2
Origin           : IGP                  Segments         : 0
MED              : 10                   Local Preference : None
Refs             : 4                    ASes             : 0
Flags            : Imported
-------------------------------------------------------------------------------
Path: No As-Path
-------------------------------------------------------------------------------
Next Hop         : 10.44.10.21
Origin           : IGP                  Segments         : 0
MED              : None                 Local Preference : 100
Refs             : 1082                 ASes             : 0
Flags            : IBGP-learned
Cluster          : 10.10.10.12
Originator Id    : 10.10.10.21
-------------------------------------------------------------------------------
Paths : 3
===============================================================================
*A:7705_ALU-2>show>router>bgp#
Table 13. BGP Path Field Descriptions

Label

Description

BGP Router ID

The local BGP router ID

AS

The configured autonomous system number

Local AS

The configured local AS setting. If not configured, then the value is the same as the AS.

Path

The AS path attribute

Next Hop

The advertised BGP next hop

Origin

EGP: the NLRI is learned by an EGP protocol

IGP: the NLRI is interior to the originating AS

Incomplete: NLRI was learned another way

Segments

The number of segments in the AS path attribute

MED

The Multi-Exit Discriminator value

Local Preference

The local preference value. This value is used if the BGP route arrives from a BGP peer without the Local Pref attribute set. It is overridden by any value set via a route policy.

Refs

The number of routes using a specified set of path attributes

ASes

The number of autonomous system numbers in the AS path attribute

Flags

IBGP-learned: path attributes learned by an IBGP peering

Community

The BGP community attribute list

Cluster List

The route reflector cluster list

Originator ID

The originator ID path attribute value
routes
Syntax

routes [ip-prefix/mask | ip-address]

routes aspath-regex reg-exp {detail |longer}

routes aspath-regex reg-exp

routes aspath-regex reg-exp hunt

routes bgp-ls [hunt] [node | link | ipv4-prefix [ipv4-prefix/mask-len]]

routes brief

routes community comm-id {detail |longer}

routes community comm-id

routes community comm-id hunt

routes detail

routes hunt [brief]

routes ipv4 [aspath-regex reg-exp] [community comm-id] [brief] [all]

routes ipv4 [aspath-regex reg-exp] hunt [community comm-id [brief] [all]

routes ipv4 [detail |longer] [aspath-regex reg-exp] [community comm-id] [all]

routes ipv6 [aspath-regex reg-exp] [community comm-id] [brief] [all]

routes ipv6 [aspath-regex reg-exp] hunt [community comm-id] [brief] [all]

routes ipv6 [detail |longer] [aspath-regex reg-exp] [community comm-id] [all]

routes label-ipv4 [aspath-regex reg-exp] [community comm-id] [brief] [all]

routes label-ipv4 [aspath-regex reg-exp] hunt [community comm-id] [brief] [all]

routes label-ipv4 [detail | longer] [aspath-regex reg-exp] [community comm-id] [all]

routes label-ipv6 [aspath-regex reg-exp] [community comm-id] [brief] [all]

routes label-ipv6 [aspath-regex reg-exp] hunt [community comm-id] [brief] [all]

routes label-ipv6 [detail | longer] [aspath-regex reg-exp] [community comm-id] [all]

routes longer

routes mvpn-ipv4 [aspath-regex reg-exp] [community comm-id] [rd rd] [brief] [type mvpn-type] [originator-ip ip-address] [source-ip ipv4 address | ipv6 address] [group-ip ipv4 address | ipv6 address] [source-as as-number]

routes mvpn-ipv4 [aspath-regex reg-exp] hunt [community comm-id] [rd rd] [brief] [type mvpn-type] [originator-ip ip-address] [source-ip ipv4 address | ipv6 address] [group-ip ipv4 address | ipv6 address] [source-as as-number]

routes mvpn-ipv4 [detail |longer] [aspath-regex reg-exp] [community comm-id] [rd rd] [type mvpn-type] [originator-ip ip-address] [source-ip ipv4 address | ipv6 address] [group-ip ipv4 address | ipv6 address] [source-as as-number]

routes route-target [source-as as-number] [brief] [aspath-regex reg-exp] [community comm-id]

routes route-target [rtc-prefix rtc-prefix] [hunt] [brief] [aspath-regex reg-exp] [community comm-id]

routes route-target rtc-prefix rtc-prefix [aspath-regex reg-exp] [community comm-id]

routes route-target [rtc-prefix rtc-prefix] [detail | longer] [aspath-regex reg-exp] [community comm-id]

routes vpn-ipv4 [aspath-regex reg-exp] [community comm-id] [rd rd] [brief]

routes vpn-ipv4 [aspath-regex reg-exp] hunt [community comm-id] [rd rd] [brief]

routes vpn-ipv4 [detail |longer] [aspath-regex reg-exp] [community comm-id] [rd rd]

routes vpn-ipv6 [aspath-regex reg-exp] [community comm-id] [rd rd] [brief]

routes vpn-ipv6 [aspath-regex reg-exp] hunt [community comm-id] [rd rd] [brief]

routes vpn-ipv6 [detail |longer] [aspath-regex reg-exp] [community comm-id] [rd rd]

Context

show>router>bgp

Description

This command displays BGP route information.

When this command is issued without any parameters, the entire BGP routing table displays.

When this command is issued with an IP prefix/mask or IP address, the best match for the parameter displays.

Note: To apply a family filter to the route output of the command, the family name must be specified before all other filtering parameters except for the IP prefix/mask or IP address, which, if present, must be placed before the family name in the command.
Parameters
ip-prefix/mask | ip-address

displays parameters that match the specified IPv4 prefix and mask length or IPv6 address (256 characters maximum)

Values

ip-prefix:  a.b.c.d (host bits must be 0)

mask: 0 to 32

ip-address:  x:x:x:x:x:x:x:x[-interface]  x:x:x:x:x:x:d.d.d.d[-interface] interface - 32 chars max, mandatory for link local addresses  x: [0 to FFFF]H  d: [0 to 255]D

aspath-regex reg-exp

displays all routes with an AS path matching the specified regular expression (80 characters maximum)

bgp-ls

displays BGP Link State routes

ipv4-prefix

displays BGP LS NLRI of type IPv4 Prefix

link

displays BGP Link State NLRI of type Link

node

displays BGP Link State NLRI of type Node

brief

provides a summarized display of the set of peers to which a BGP route is advertised; this option is only supported when no IP prefix/mask or IP address is specified

community

displays all routes with the specified BGP community; community matching is based only on RIB-In communities, not RIB-Out communities

comm-id

specifies community IDs, in the format as-number1:comm-val1 | ext-comm | well-known-comm

Values

as-number1

0 to 65535

comm-val1

0 to 65535

ext-comm

type:{ip-address:comm-val1 | as-number1:comm-val2 |as-number2:comm-val1 | as-number1:val-in-mbps} ext:xxyy:ovstate

where

type: target | origin | bandwidth (keywords)

ip-address:

ipv4-address: a.b.c.d

ipv6-address: x:x:x:x:x:x:x:x[-interface]  x:x:x:x:x:x:d.d.d.d[-interface] interface - 32 chars max,  mandatory for link local addresses  x: [0 to FFFF]H  d: [0 to 255]D

ext:xxyy:ovstate

xx: 43

yy: 0

ovstate: 0, 1, 2 (0 for valid, 1 for not-found, 2 for invalid)

well-known-comm

null | no-export | no-export-subconfed | no-advertise (keywords)

group-ip ipv4 address | ipv6 address

displays the group IPv4 or IPv6 address

originator-ip ip-address

displays the originating IPv4 or IPv6 address

source-ip ipv4 address | ipv6 address

displays the source IPv4 or IPv6 address

detail

displays a more detailed version of the output

source-as as-number

displays the source AS number

hunt

displays entries for the specified route in the RIB-In, RIB-Out, and RTM

ipv4

displays only those BGP peers that have the IPv4 family enabled

ipv6

displays only those BGP peers that have the IPv6 family enabled

label-ipv4

displays only those BGP peers for the labeled IPv4 unicast address family

label-ipv6

displays only those BGP peers for the labeled IPv6 unicast address family

longer

displays the specified route and subsets of the route

mvpn-ipv4

displays the BGP peers that are MVPN-IPv4 capable

mvpn-type

the specified MVPN type for which to display information

Values

intra-ad | inter-ad | spmsi-ad | leaf-ad | source-ad | shared-join | source-join

route-target

displays a summary of route target constrained routes for this BGP peer

rtc-prefix rtc-prefix

displays route target constraint prefix information, in the format source-as:{ip-addr:comm-val | 2byte-asnumber:ext-comm-val | 4byte-asnumber:comm-val}/prefix-length

Values

ip-addr:

ipv4-address:  a.b.c.d

ipv6-address:  x:x:x:x:x:x:x:x[-interface]  x:x:x:x:x:x:d.d.d.d[-interface] interface - 32 chars max,  mandatory for link local addresses  x: [0 to FFFF]H  d: [0 to 255]D

comm-val: 0 to 65535

2byte-asnumber: 0 to 65535

ext-comm-val: 0 to 4294967295

4byte-asnumber: 0 to 4294967295

prefix-length: 0 to 96

rd rd

displays the route distinguisher value, in the format ip-addr:comm-val | 2byte-asnumber:ext-comm-val | 4-byte-asnumber:comm-val

Values

ip-addr:

ipv4-address:  a.b.c.d

ipv6-address:  x:x:x:x:x:x:x:x[-interface]  x:x:x:x:x:x:d.d.d.d[-interface] interface - 32 chars max,  mandatory for link local addresses  x: [0 to FFFF]H  d: [0 to 255]D

comm-val: 0 to 65535

2byte-asnumber: 0 to 65535

ext-comm-val: 0 to 4294967295

4byte-asnumber: 0 to 4294967295

vpn-ipv4

displays the BGP VPN IPv4 routes

vpn-ipv6

displays the BGP VPN IPv6 routes

originator-ip ip-address

filters BGP MVPN routes by the originating router IP address that is found in the intra-AD (auto-discovery) MVPN routes

source-ip ip-address

filters BGP MVPN routes by the source IP address that is found in the source-join, source-AD, or S-PMSI-AD MVPN routes

group-ip ip-address

filters BGP MVPN routes by the multicast group IP address that is found in the source-join, source-AD, or S-PMSI-AD MVPN routes

source-as as-number

filters BGP MVPN routes by source-AS (autonomous system) extended community attribute

Output

The following output is an example of BGP route information, and BGP Route Field Descriptions describes the fields.

Output Example 
*A:Sar18 Dut-B# show router bgp routes 10.10.10.5 
===============================================================================
 BGP Router ID:10.20.1.3        AS:100         Local AS:100
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
 Origin codes  : i - IGP, e - EGP, ? - incomplete
===============================================================================
BGP IPv4 Routes
===============================================================================
Flag  Network                                            LocalPref   MED
      Nexthop (Router)                                   Path-Id     Label
      As-Path
-------------------------------------------------------------------------------
u*>?  10.10.10.0/24                                      None        None
      10.20.1.4                                          None        -
      200 300
-------------------------------------------------------------------------------
Routes : 1
===============================================================================
*A:Sar18 Dut-B##


*A:Sar18 Dut-B# show>router>bgp# routes vpn-ipv4 10.10.10.6/32 rd 10.20.1.4:1 hunt
===============================================================================
 BGP Router ID:10.20.1.3        AS:None        Local AS:100
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best, b - backup
===============================================================================
BGP VPN-IPv4 Routes
===============================================================================
-------------------------------------------------------------------------------
RIB In Entries
-------------------------------------------------------------------------------
Network        : 10.10.10.6/32
Nexthop        : 10.20.1.4
Route Dist.    : 10.20.1.4:1            VPN Label      : 131070
Path Id        : None
From           : 10.20.1.4
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : int_to_D
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : None
AIGP Metric    : None
Connector      : None
Community      : target:100:100
Cluster        : No Cluster Members
Originator Id  : None                   Peer Router Id : 10.20.1.4
Fwd Class      : None                   Priority       : None
Flags          : Used  Valid  Best  Incomplete
Route Source   : Internal
AS-Path        : 106
VPRN Imported  :  1
-------------------------------------------------------------------------------
RIB Out Entries
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
Routes : 1
===============================================================================
*A:Sar18 Dut-B#


*A:Sar18 Dut-B# show>router>bgp# routes 3FFE::606:609/128 vpn-ipv6 hunt
===============================================================================
 BGP Router ID:10.20.1.3        AS:None        Local AS:100
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best, b - backup
===============================================================================
BGP VPN-IPv6 Routes
===============================================================================
-------------------------------------------------------------------------------
RIB In Entries
-------------------------------------------------------------------------------
Network        : 3FFE::606:609/128
Nexthop        : ::FFFF:A14:104
Route Dist.    : 10.20.1.4:1            VPN Label      : 131070
Path Id        : None
From           : 10.20.1.4
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : int_to_D
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : None
AIGP Metric    : None
Connector      : None
Community      : target:100:100
Cluster        : No Cluster Members
Originator Id  : None                   Peer Router Id : 10.20.1.4
Fwd Class      : None                   Priority       : None
Flags          : Used  Valid  Best  Incomplete
Route Source   : Internal
AS-Path        : 106
VPRN Imported  :  1
-------------------------------------------------------------------------------
RIB Out Entries
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
Routes : 1
===============================================================================
*A:Sar18 Dut-B#


*A:Sar18 Dut-B# show>router>bgp# routes vpn-ipv6 3FFE::606:607 128 rd 10.20.1.4:1
hunt
===============================================================================
 BGP Router ID:10.20.1.3        AS:None        Local AS:100
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best, b - backup
===============================================================================
BGP VPN-IPv6 Routes
===============================================================================
-------------------------------------------------------------------------------
RIB In Entries
-------------------------------------------------------------------------------
Network        : 3FFE::606:607/128
Nexthop        : ::FFFF:A14:104
Route Dist.    : 10.20.1.4:1            VPN Label      : 131070
Path Id        : None
From           : 10.20.1.4
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : int_to_D
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : None
AIGP Metric    : None
Connector      : None
Community      : target:100:100
Cluster        : No Cluster Members
Originator Id  : None                   Peer Router Id : 10.20.1.4
Fwd Class      : None                   Priority       : None
Flags          : Used  Valid  Best  Incomplete
Route Source   : Internal
AS-Path        : 106
VPRN Imported  :  1
-------------------------------------------------------------------------------
RIB Out Entries
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
Routes : 1
===============================================================================
*A:Sar18 Dut-B#


*A:Sar18 Dut-B# show>router>bgp# routes vpn-ipv6 3FFE::606:607/128 rd 10.20.1.4:2 
hunt
===============================================================================
 BGP Router ID:10.20.1.3        AS:None        Local AS:100
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best, b - backup
===============================================================================
BGP VPN-IPv6 Routes
===============================================================================
No Matching Entries Found
===============================================================================
*A:Sar18 Dut-B#


*A:Sar18 Dut-B# show router bgp routes hunt 10.10.10.1/32
===============================================================================
 BGP Router ID:10.20.1.3        AS:5000        Local AS:5000
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid 
                 l - leaked, x - stale, > - best, b - backup, p - purge 
Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best
===============================================================================
BGP IPv4 Routes
===============================================================================
-------------------------------------------------------------------------------
RIB In Entries
-------------------------------------------------------------------------------
Network        : 10.10.10.1/32
Nexthop        : 10.20.1.1
From           : 10.20.1.1
Res. Nexthop   : 10.20.1.1 (RSVP LSP: 1)
Local Pref.    : 100                    Interface Name : ip-10.10.2.3
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : None
Community      : No Community Members
Cluster        : No Cluster Members
Originator Id  : None                   Peer Router Id : 10.20.1.1
Flags          : Used  Valid  Best  Incomplete
AS-Path        : No As-Path
-------------------------------------------------------------------------------
RIB Out Entries
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
Routes : 1
===============================================================================
*A:Sar18 Dut-B#


*A:Sar18 Dut-B# show router bgp routes family ipv4
===============================================================================
 BGP Router ID : 10.10.10.103      AS : 200     Local AS : 200
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best
===============================================================================
BGP Routes
===============================================================================
Flag  Network                             Nexthop         LocalPref  MED
      VPN Label                           As-Path
-------------------------------------------------------------------------------
No Matching Entries Found
===============================================================================
*A:Sar18 Dut-B#


*A:Sar18 Dut-B# show router bgp routes 10.10.10.0/24 detail
=============================================================================== 
BGP Router ID : 10.128.0.161 AS : 65535 Local AS : 65535
=============================================================================== 
Legend -
 Status codes : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
 Origin codes : i - IGP, e - EGP, ? - incomplete, > - best
=============================================================================== 
BGP Routes 
=============================================================================== 
Original Attributes 
Network         :       10.10.10.0/24   Nexthop          :     10.20.1.20 
Route Dist.     :       10070:100       VPN Label        :     152784 
From            :       10.20.1.20      Res. Nexthop     :     10.130.0.2 
Local Pref.     :       100 
Aggregator AS   :       none            Aggregator       :     none 
Atomic Aggr.    :       Not Atomic      MED              :     none 
Community       :       target:10070:1
Cluster         :       No Cluster Members 
Originator Id   :       None            Peer Router Id   : 10.20.1.20 
Flags           :       Used Valid Best IGP 
AS-Path         :       10070 {14730} 
Modified Attributes 

Network :10.10.10.0/24 Nexthop :10.20.1.20 
Route Dist.: 10001:100 VPN Label :152560
From :10.20.1.20 Res. Nexthop :10.130.0.2 
Local Pref.:100 
Aggregator AS: none Aggregator:none 
Atomic Aggr.:Not Atomic MED :none 
Community :target:10001:1 
Cluster :No Cluster Members 
Originator Id:None Peer Router Id:10.20.1.20 
Flags :Used Valid Best IGP 
AS-Path :No As-Path 
------------------------------------------------------------------------------- 
*A:Sar18 Dut-B#


*A:Sar18 Dut-B# show router bgp routes 10.10.10.0/24 hunt 
===============================================================================
 BGP Router ID : 10.20.1.1   AS : 100Local AS : 100 
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best
===============================================================================
BGP Routes
===============================================================================
RIB In Entries
-------------------------------------------------------------------------------
Network        : 10.10.10.0/24
Nexthop        : 10.20.1.2
Route Dist.    : 10.20.1.2:1VPN Label: 131070 
From       : 10.20.1.2
Res. Nexthop   : 10.10.1.2
Local Pref.    : 100Interface Name: to-sr7 
Aggregator AS  : noneAggregator: none 
Atomic Aggr.   : Not AtomicMED: none
Community      : target:10.20.1.2:1
Cluster        : No Cluster Members
Originator Id  : NonePeer Router Id: 10.20.1.2
Flags       : Used  Valid  Best  IGP  
AS-Path        : No As-Path
VPRN Imported  : 1 2 10 12
-------------------------------------------------------------------------------
RIB Out Entries
-------------------------------------------------------------------------------
Routes : 1
===============================================================================
*A:Sar18 Dut-B#


*A:Sar18 Dut-B# show router bgp routes mvpn-ipv4
===============================================================================
 BGP Router ID:10.20.1.3        AS:200         Local AS:200
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP           LocalPref   MED
          RD                          SourceAS                           VPNLabel
          Nexthop                     SourceIP
          As-Path                     GroupIP
-------------------------------------------------------------------------------
u*>i  Intra-Ad                    10.20.1.4              100         0
          1:1                         -                                  -
          10.20.1.4                   -
          No As-Path                  -
u*>i  Source-Ad                   -                      100         0
          1:1                         -                                  -
          10.20.1.4                   10.100.1.2
          No As-Path                  10.0.0.0
u*>i  Source-Join                 -                      100         0
          1:1                         200                                -
          10.20.1.4                   10.100.1.2
          No As-Path                  10.0.0.0
-------------------------------------------------------------------------------
Routes : 3
===============================================================================
*A:Sar18 Dut-B#


*A:Sar18 Dut-B# show router bgp routes mvpn-ipv4 brief
===============================================================================
 BGP Router ID:10.20.1.3        AS:200         Local AS:200
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Flag  RouteType                   OriginatorIP          SourceIP
          RD                          SourceAS              GroupIP
-------------------------------------------------------------------------------
u*>i  Intra-Ad                    10.20.1.4             -
          1:1                         -                     -
u*>i  Source-Ad                   -                      10.100.1.2
          1:1                         -                      10.0.0.0
u* >i  Source-Join                 -                     10.100.1.2
          1:1                         200                   10.0.0.0
-------------------------------------------------------------------------------
Routes : 3
===============================================================================
*A:Sar18 Dut-B# 


*A:Sar18 Dut-B# show router bgp routes mvpn-ipv4 type source-join source-as 200  
                source-ip 10.100.1.2 group-ip 10.0.0.0 detail
===============================================================================
 BGP Router ID:10.20.1.3        AS:200         Local AS:200
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best
 
===============================================================================
BGP MVPN-IPv4 Routes
===============================================================================
Route Type     : Source-Join
Route Dist.    : 1:1
Source AS      : 200
Source IP      : 10.100.1.2
Group IP       : 10.0.0.0
Nexthop        : 10.20.1.4
From           : 10.20.1.4
Res. Nexthop   : 10.0.0.0
Local Pref.    : 100                    Interface Name : NotAvailable
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 0
Community      : target:10.20.1.3:2
Cluster        : No Cluster Members
Originator Id  : None                   Peer Router Id : 10.20.1.4
Flags          : Used  Valid  Best  IGP
AS-Path        : No As-Path
-------------------------------------------------------------------------------
Routes : 1
===============================================================================
*A:Sar18 Dut-B#


*A:Sar18 Dut-B# show router bgp routes ipv4 detail
===============================================================================
 BGP Router ID:10.1.1.1          AS:100         Local AS:100
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best, b - backup
===============================================================================
BGP IPv4 Routes
===============================================================================
-------------------------------------------------------------------------------
Original Attributes

Network        : 10.1.1.1/32
Nexthop        : 192.168.1.1
Path Id        : None
From           : 192.168.1.1
Res. Nexthop   : 192.168.1.1
Local Pref.    : n/a                    Interface Name : net
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 5000
AIGP Metric    : 100     
Community      : None
Cluster        : No Cluster Members
Originator Id  : None                   Peer Router Id : 2.2.2.2
Fwd Class      : None                   Priority       : None
Flags          : Used  Valid  Best  Incomplete
Route Source   : External
AS-Path        : 200 400 500

Modified Attributes

Network        : 10.1.1.1/32
Nexthop        : 192.168.1.1
Path Id        : None
From           : 192.168.1.1
Res. Nexthop   : 192.168.1.1
Local Pref.    : None                   Interface Name : net
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 5000
AIGP Metric    : 110
Community      : None
Cluster        : No Cluster Members
Originator Id  : None                   Peer Router Id : 2.2.2.2
Fwd Class      : None                   Priority       : None
Flags          : Used  Valid  Best  Incomplete
Route Source   : External
AS-Path        : 200 400 500
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
Routes : 1
===============================================================================
*A:Sar18 Dut-B#


*A:Sar18 Dut-B# show router bgp routes 10.1.1.1/32 hunt
===============================================================================
 BGP Router ID:1.1.1.1          AS:100         Local AS:100
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best, b - backup
===============================================================================
BGP IPv4 Routes
===============================================================================
-------------------------------------------------------------------------------
RIB In Entries
-------------------------------------------------------------------------------
Network        : 10.1.1.1/32
Nexthop        : 192.168.1.1
Path Id        : None
From           : 192.168.1.1
Res. Nexthop   : 192.168.1.1
Local Pref.    : None                   Interface Name : net
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 5000
AIGP Metric    : 110
Community      : None
Cluster        : No Cluster Members
Originator Id  : None                   Peer Router Id : 2.2.2.2
Fwd Class      : None                   Priority       : None
Flags          : Used  Valid  Best  Incomplete
Route Source   : External
AS-Path        : 200 400 500
-------------------------------------------------------------------------------
RIB Out Entries
-------------------------------------------------------------------------------
Network        : 10.1.1.1/32
Nexthop        : 10.1.1.1
Path Id        : None
To             : 10.3.3.3
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : NotAvailable
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 5000
AIGP Metric    : 150
Community      : None
Cluster        : No Cluster Members
Originator Id  : None                   Peer Router Id : 10.3.3.3
Origin         : Incomplete
AS-Path        : 200 400 500
-------------------------------------------------------------------------------
Routes : 2
===============================================================================
*A:Sar18 Dut-B#


*A:Sar18 Dut-B# show router bgp routes 
===============================================================================
 BGP Router ID:10.20.1.1        AS:1           Local AS:1          
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
 Origin codes  : i - IGP, e - EGP, ? - incomplete, > - best, b - backup
===============================================================================
BGP IPv4 Routes
===============================================================================
Flag  Network                                            LocalPref     MED
      Nexthop                                              Path-Id      Label
      As-Path                                                                 
-------------------------------------------------------------------------------
u*>i  10.0.0.1/32                                        100         2010
      10.20.1.2                                             None        131057
      2       
ub*i  10.0.0.1/32                                        100         2010
      10.20.1.3                                             None        131067
      2
-------------------------------------------------------------------------------
Routes : 2
===============================================================================
*A:Sar18 Dut-B#

*A:Sar18# show router bgp routes vpn-ipv4 community target:100.100.100.100:2 hunt 
===============================================================================
BGP Router ID:10.20.1.6        AS:62000       Local AS:62000      
===============================================================================
Legend -
Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge 
                 l - leaked, x - stale, > - best, b - backup, p - purge
Origin codes  : i - IGP, e - EGP, ? - incomplete
===============================================================================
BGP VPN-IPv4 Routes
===============================================================================
-------------------------------------------------------------------------------
RIB In Entries
-------------------------------------------------------------------------------
Network        : 10.1.1.1/32
Nexthop        : 10.20.1.6
Route Dist.    : 100.100.100.100:2      VPN Label      : 131068
Path Id        : None                   
From           : 10.20.1.5
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : system
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 100
AIGP Metric    : None                   
Connector      : None
Community      : target:100.100.100.100:2
Cluster        : 5.5.5.5
Originator Id  : 10.20.1.6              Peer Router Id : 10.20.1.5
Flags          : Invalid  IGP  
Route Source   : Internal
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
Add Paths Send : Default                
Last Modified  : 00h00m06s              
VPRN Imported  : None
-------------------------------------------------------------------------------
RIB Out Entries
-------------------------------------------------------------------------------
Network        : 10.1.1.1/32
Nexthop        : 10.20.1.6
Route Dist.    : 100.100.100.100:2      VPN Label      : 131068
Path Id        : None                   
To             : 10.20.1.5
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : NotAvailable
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : None
AIGP Metric    : None                   
Connector      : None
Community      : target:100.100.100.100:2
Cluster        : No Cluster Members
Originator Id  : None                   Peer Router Id : 10.20.1.5
Origin         : IGP                    
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
-------------------------------------------------------------------------------
Routes : 2
===============================================================================
*A:Sar18# 

*A:Sar18# show router bgp routes  vpn-ipv6  community target:100.100.100.100:2 hunt 
===============================================================================
 BGP Router ID:10.20.1.3        AS:61000       Local AS:61000      
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge
 Origin codes  : i - IGP, e - EGP, ? - incomplete
===============================================================================
BGP VPN-IPv6 Routes
===============================================================================
-------------------------------------------------------------------------------
RIB In Entries
-------------------------------------------------------------------------------
Network        : 3ffe::100:0/109
Nexthop        : ::ffff:10.20.1.1
Route Dist.    : 1:1234                 VPN Label      : 131067
Path Id        : None                   
From           : 10.20.1.2
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : toA
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 100
AIGP Metric    : None                   
Connector      : None
Community      : 0:0 target:100.100.100.100:2 target:1:123456
                 origin:100.100.100.100:2
Cluster        : 2.2.2.2
Originator Id  : 10.20.1.1              Peer Router Id : 10.20.1.2
Flags          : Used  Valid  Best  IGP  
Route Source   : Internal
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
Add Paths Send : Default                
Last Modified  : 00h03m41s              
VPRN Imported  :  3  1
 
Network        : 3ffe::101:100/120
Nexthop        : ::ffff:10.20.1.1
Route Dist.    : 1:1234                 VPN Label      : 131067
Path Id        : None                   
From           : 10.20.1.2
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : toA
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 100
AIGP Metric    : None                   
Connector      : None
Community      : 0:0 target:100.100.100.100:2 target:1:123456
                 origin:100.100.100.100:2
Cluster        : 2.2.2.2
Originator Id  : 10.20.1.1              Peer Router Id : 10.20.1.2
Flags          : Used  Valid  Best  IGP  
Route Source   : Internal
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
Add Paths Send : Default                
Last Modified  : 00h03m41s              
VPRN Imported  :  3  1
 
Network        : 3ffe::101:100/123
Nexthop        : ::ffff:10.20.1.1
Route Dist.    : 1:1234                 VPN Label      : 131067
Path Id        : None                   
From           : 10.20.1.2
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : toA
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 100
AIGP Metric    : None                   
Connector      : None
Community      : 0:0 target:100.100.100.100:2 target:1:123456
                 origin:100.100.100.100:2
Cluster        : 2.2.2.2
Originator Id  : 10.20.1.1              Peer Router Id : 10.20.1.2
Flags          : Used  Valid  Best  IGP  
Route Source   : Internal
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
Add Paths Send : Default                
Last Modified  : 00h03m41s              
VPRN Imported  :  3  1
 
Network        : 3ffe::300:0/104
Nexthop        : ::ffff:10.20.1.1
Route Dist.    : 1:1234                 VPN Label      : 131067
Path Id        : None                   
From           : 10.20.1.2
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : toA
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 100
AIGP Metric    : None                   
Connector      : None
Community      : 0:0 target:100.100.100.100:2 target:1:123456
                 origin:123456:2
Cluster        : 2.2.2.2
Originator Id  : 10.20.1.1              Peer Router Id : 10.20.1.2
Flags          : Used  Valid  Best  IGP  
Route Source   : Internal
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
Add Paths Send : Default                
Last Modified  : 00h03m41s              
VPRN Imported  :  3  1
 
Network        : 3ffe::303:300/120
Nexthop        : ::ffff:10.20.1.1
Route Dist.    : 1:1234                 VPN Label      : 131067
Path Id        : None                   
From           : 10.20.1.2
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : toA
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 100
AIGP Metric    : None                   
Connector      : None
Community      : 0:0 target:100.100.100.100:2 target:1:123456
                 origin:123456:2
Cluster        : 2.2.2.2
Originator Id  : 10.20.1.1              Peer Router Id : 10.20.1.2
Flags          : Used  Valid  Best  IGP  
Route Source   : Internal
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
Add Paths Send : Default                
Last Modified  : 00h03m41s              
VPRN Imported  :  3  1
 
Network        : ::/0
Nexthop        : ::ffff:10.20.1.1
Route Dist.    : 100.100.100.100:2      VPN Label      : 131069
Path Id        : None                   
From           : 10.20.1.2
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : toA
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 100
AIGP Metric    : None                   
Connector      : None
Community      : target:100.100.100.100:2 origin:100.100.100.100:2
                 origin:1:123456
Cluster        : 2.2.2.2
Originator Id  : 10.20.1.1              Peer Router Id : 10.20.1.2
Flags          : Used  Valid  Best  IGP  
Route Source   : Internal
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
Add Paths Send : Default                
Last Modified  : 00h03m42s              
VPRN Imported  :  1
 
Network        : 3ffe::100:0/104
Nexthop        : ::ffff:10.20.1.1
Route Dist.    : 100.100.100.100:2      VPN Label      : 131069
Path Id        : None                   
From           : 10.20.1.2
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : toA
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 100
AIGP Metric    : None                   
Connector      : None
Community      : 100:100 2:3 target:100.100.100.100:2
                 origin:1:123456 origin:1:2
Cluster        : 2.2.2.2
Originator Id  : 10.20.1.1              Peer Router Id : 10.20.1.2
Flags          : Used  Valid  Best  IGP  
Route Source   : Internal
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
Add Paths Send : Default                
Last Modified  : 00h03m42s              
VPRN Imported  :  1
 
Network        : 3ffe::101:0/112
Nexthop        : ::ffff:10.20.1.1
Route Dist.    : 100.100.100.100:2      VPN Label      : 131069
Path Id        : None                   
From           : 10.20.1.2
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : toA
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 100
AIGP Metric    : None                   
Connector      : None
Community      : 100:100 2:3 target:100.100.100.100:2
                 origin:100.100.100.100:2 origin:1:123456 origin:1:2
Cluster        : 2.2.2.2
Originator Id  : 10.20.1.1              Peer Router Id : 10.20.1.2
Flags          : Used  Valid  Best  IGP  
Route Source   : Internal
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
Add Paths Send : Default                
Last Modified  : 00h03m41s              
VPRN Imported  :  1
 
Network        : 3ffe::202:202/128
Nexthop        : ::ffff:10.20.1.1
Route Dist.    : 100.100.100.100:2      VPN Label      : 131069
Path Id        : None                   
From           : 10.20.1.2
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : toA
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 100
AIGP Metric    : None                   
Connector      : None
Community      : 0:0 target:100.100.100.100:2
                 origin:100.100.100.100:2 origin:1:123456
Cluster        : 2.2.2.2
Originator Id  : 10.20.1.1              Peer Router Id : 10.20.1.2
Flags          : Used  Valid  Best  IGP  
Route Source   : Internal
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
Add Paths Send : Default                
Last Modified  : 00h03m41s              
VPRN Imported  :  1
 
Network        : ::/0
Nexthop        : ::ffff:10.20.1.1
Route Dist.    : 123456:2               VPN Label      : 131068
Path Id        : None                   
From           : 10.20.1.2
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : toA
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 100
AIGP Metric    : None                   
Connector      : None
Community      : target:100.100.100.100:2 origin:100.100.100.100:2
                 origin:1:123456
Cluster        : 2.2.2.2
Originator Id  : 10.20.1.1              Peer Router Id : 10.20.1.2
Flags          : Used  Valid  Best  IGP  
Route Source   : Internal
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
Add Paths Send : Default                
Last Modified  : 00h03m41s              
VPRN Imported  :  1
 
Network        : 3ffe::100:0/104
Nexthop        : ::ffff:10.20.1.1
Route Dist.    : 123456:2               VPN Label      : 131068
Path Id        : None                   
From           : 10.20.1.2
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : toA
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 100
AIGP Metric    : None                   
Connector      : None
Community      : 100:100 2:3 target:100.100.100.100:2
                 origin:1:123456 origin:1:2
Cluster        : 2.2.2.2
Originator Id  : 10.20.1.1              Peer Router Id : 10.20.1.2
Flags          : Used  Valid  Best  IGP  
Route Source   : Internal
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
Add Paths Send : Default                
Last Modified  : 00h03m41s              
VPRN Imported  :  1
 
Network        : 3ffe::101:0/112
Nexthop        : ::ffff:10.20.1.1
Route Dist.    : 123456:2               VPN Label      : 131068
Path Id        : None                   
From           : 10.20.1.2
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : toA
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 100
AIGP Metric    : None                   
Connector      : None
Community      : 100:100 2:3 target:100.100.100.100:2
                 origin:100.100.100.100:2 origin:1:123456 origin:1:2
Cluster        : 2.2.2.2
Originator Id  : 10.20.1.1              Peer Router Id : 10.20.1.2
Flags          : Used  Valid  Best  IGP  
Route Source   : Internal
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
Add Paths Send : Default                
Last Modified  : 00h03m41s              
VPRN Imported  :  1
 
Network        : 3ffe::202:202/128
Nexthop        : ::ffff:10.20.1.1
Route Dist.    : 123456:2               VPN Label      : 131068
Path Id        : None                   
From           : 10.20.1.2
Res. Nexthop   : n/a
Local Pref.    : 100                    Interface Name : toA
Aggregator AS  : None                   Aggregator     : None
Atomic Aggr.   : Not Atomic             MED            : 100
AIGP Metric    : None                   
Connector      : None
Community      : 0:0 target:100.100.100.100:2
                 origin:100.100.100.100:2 origin:1:123456
Cluster        : 2.2.2.2
Originator Id  : 10.20.1.1              Peer Router Id : 10.20.1.2
Flags          : Used  Valid  Best  IGP  
Route Source   : Internal
AS-Path        : No As-Path
Route Tag      : 0                      
Neighbor-AS    : N/A
Add Paths Send : Default                
Last Modified  : 00h03m41s              
VPRN Imported  :  1
 
-------------------------------------------------------------------------------
RIB Out Entries
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
Routes : 13
===============================================================================
*A:Sar18# 

*A:7705:Dut-A>config>router# show router bgp routes bgp-ls
===============================================================================
 BGP Router ID:10.0.0.1         AS:1001        Local AS:1001
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge
 Origin codes  : i - IGP, e - EGP, ? - incomplete
===============================================================================
BGP-LS Node NLRIs
===============================================================================
Flag  Prot/Id                                    Nexthop         LocalPref MED
      Local Node:AS/LsID/OSPF Ar Id
       IGP Rt Id
-------------------------------------------------------------------------------
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.4
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.6
-------------------------------------------------------------------------------
Routes : 2
===============================================================================
BGP-LS Link NLRIs
===============================================================================
Flag  Prot/Id                                    Nexthop         LocalPref MED
      Local Node:AS/LsID/OSPF Ar Id
       IGP Rt Id
      Remote Node:AS/LsID/OSPF Ar Id
       IGP Rt Id
      Link: Local Id/Remote Id
       IPv4 Inf/Neighbor
       IPv6 Inf/Neighbor
-------------------------------------------------------------------------------
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.6
      0.0.7.208/-/0.0.0.0
       10.0.0.4
      --/-
       1.46.0.6/-
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.4
      0.0.7.208/-/0.0.0.0
       10.0.0.6
      --/-
       1.46.0.4/-
-------------------------------------------------------------------------------
Routes : 2
===============================================================================
BGP-LS Ipv4 NLRIs
===============================================================================
Flag  Prot/Id                                    Nexthop         LocalPref MED
      Local Node:AS/LsID/OSPF Ar Id
       IGP Rt Id
      Prefix Desc:MT ID/OSPF Rt Type
       IP Reachability Addr/Prefix Len
-------------------------------------------------------------------------------
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.6
      -/Intra
       1.46.0.0/24
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.4
      -/Intra
       10.0.0.4/32
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.6
      -/Intra
       10.0.0.6/32
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.4
      -/Intra
       1.46.0.0/24
-------------------------------------------------------------------------------
Routes : 4
-------------------------------------------------------------------------------
Total Routes : 8
===============================================================================
*A:7705:Dut-A>config>router#

*A:7705:Dut-A>config>router# show router bgp routes bgp-ls node
===============================================================================
 BGP Router ID:10.0.0.1         AS:1001        Local AS:1001
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge
 Origin codes  : i - IGP, e - EGP, ? - incomplete
===============================================================================
BGP-LS Node NLRIs
===============================================================================
Flag  Prot/Id                                    Nexthop         LocalPref MED
      Local Node:AS/LsID/OSPF Ar Id
       IGP Rt Id
-------------------------------------------------------------------------------
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.4
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.6
-------------------------------------------------------------------------------
Routes : 2
===============================================================================
*A:7705:Dut-A>config>router#

*A:7705:Dut-A>config>router# show router bgp routes bgp-ls link
===============================================================================
 BGP Router ID:10.0.0.1         AS:1001        Local AS:1001
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge
 Origin codes  : i - IGP, e - EGP, ? - incomplete
===============================================================================
BGP-LS Link NLRIs
===============================================================================
Flag  Prot/Id                                    Nexthop         LocalPref MED
      Local Node:AS/LsID/OSPF Ar Id
       IGP Rt Id
      Remote Node:AS/LsID/OSPF Ar Id
       IGP Rt Id
      Link: Local Id/Remote Id
       IPv4 Inf/Neighbor
       IPv6 Inf/Neighbor
-------------------------------------------------------------------------------
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.6
      0.0.7.208/-/0.0.0.0
       10.0.0.4
      --/-
       1.46.0.6/-
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.4
      0.0.7.208/-/0.0.0.0
       10.0.0.6
      --/-
       1.46.0.4/-
-------------------------------------------------------------------------------
Routes : 2
===============================================================================
*A:7705:Dut-A>config>router#

*A:7705:Dut-A>config>router# show router bgp routes bgp-ls ipv4-prefix
===============================================================================
 BGP Router ID:10.0.0.1         AS:1001        Local AS:1001
===============================================================================
 Legend -
 Status codes  : u - used, s - suppressed, h - history, d - decayed, * - valid
                 l - leaked, x - stale, > - best, b - backup, p - purge
 Origin codes  : i - IGP, e - EGP, ? - incomplete
===============================================================================
BGP-LS Ipv4 NLRIs
===============================================================================
Flag  Prot/Id                                    Nexthop         LocalPref MED
      Local Node:AS/LsID/OSPF Ar Id
       IGP Rt Id
      Prefix Desc:MT ID/OSPF Rt Type
       IP Reachability Addr/Prefix Len
-------------------------------------------------------------------------------
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.6
      -/Intra
       1.46.0.0/24
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.4
      -/Intra
       10.0.0.4/32
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.6
      -/Intra
       10.0.0.6/32
*>i   OSPFv2/0                                   1.13.0.3        n/a       None
      0.0.7.208/-/0.0.0.0
       10.0.0.4
      -/Intra
       1.46.0.0/24
-------------------------------------------------------------------------------
Routes : 4
===============================================================================
*A:7705:Dut-A>config>router#
Table 14. BGP Route Field Descriptions

Label

Description

BGP Router ID

The local BGP router ID

AS

The configured autonomous system number

Local AS

The configured local AS setting. If not configured, the value is the same as the AS.

Flag/Flags

Legend:

Status codes:

 u - used

 s - suppressed

 h - history

 d - decayed

* - valid

 If an * is not present, the status is invalid

 l - leaked

 x - stale

> - best

 b - backup

 p - purge

Origin codes:

 i - IGP

 e - EGP

? - incomplete

> - best

Network

The IP prefix and mask length

Nexthop

The BGP next hop

AS-Path

The BGP AS path attribute

Local Pref.

The local preference value. This value is used if the BGP route arrives from a BGP peer without the Local Pref attribute set. It is overridden by any value set via a route policy.

MED

The MED metric value

none: MED metrics are not present

VPN Label

 The label generated by the PE label manager

Original Attributes

The received BGP attributes of a route from a peer without any modification from any policy

Modified Attributes

The final BGP attributes of a route after the policies evaluation

Route Dist.

The route distinguisher identifier attached to routes that distinguishes the VPN it belongs to

From

The advertising BGP neighbor IP address

Res. Nexthop

The resolved next hop

Aggregator AS

The aggregator AS value

none: aggregator AS attributes are not present

Aggregator

The aggregator attribute value

none: aggregator attributes are not present

Atomic Aggr.

Atomic: the atomic aggregator flag is set

Not Atomic: the atomic aggregator flag is not set

Community

The BGP community attribute list

Cluster

The route reflector cluster list

Originator Id

The originator ID path attribute value

none: the originator ID attribute is not present

Peer Router Id

The router ID of the advertising router

TieBreakReason

The step in the BGP decision process where a BGP route lost the tiebreaker with the next BGP route for the same prefix

LocalPref — this route is not the best because the next better route has a higher LOCAL_PREF

AIGP — this route is not the best because the next better route has a lower derived AIGP metric value

ASPathLen — this route is not the best because the next better route has a shorter AS PATH length

Origin — this route is not the best because the next better route has a lower origin value

MED — this route is not the best because the next better route has a lower MED, and MED comparison of the routes was allowed

IBGP — this IBGP route is not the best because the next better route is an EBGP route

NHCost — this route is not the best because the next better route has a lower metric value to reach the BGP NEXT HOP

BGPID — this route is not the best because the next better route has a lower originator ID or BGP identifier

ClusterLen — this route is not the best because the next better route has a shorter cluster list length

PeerIP — this route is not the best because the next better route has a lower neighbor IP address

VPRN Imported

The VPRNs where a particular BGP-VPN received route has been imported and installed

BGP-LS Node NLRIs

BGP-LS NLRI of type Node

BGP-LS Link NLRIs

BGP-LS NLRI of type Link

BGP-LS Ipv4 NLRIs

BGP-LS NLRI of type IPv4 Prefix
summary
Syntax

summary [all]

summary [family family] [neighbor ip-address]

Context

show>router>bgp

Description

This command displays a summary of BGP neighbor information.

If confederations are not configured, that portion of the output will not display.

The ‟State” field displays the global BGP operational state. The valid values are:

  • Up — BGP global process is configured and running

  • Down — BGP global process is administratively shut down and not running

  • Disabled — BGP global process is operationally disabled. The process must be restarted by the operator.

For example, if a BGP peer is operationally disabled, then the state in the summary table shows the state ‛Disabled’.

Parameters
all

displays BGP peers in all instances

family

displays only those BGP peers that have the specified address family enabled

Values

ipv4 | vpn-ipv4 | ipv6 | vpn-ipv6 | mvpn-ipv4 | route-target | evpn | label-ipv4 | label-ipv6 | bgp-ls

ip-address

clears damping information for entries received from the BGP neighbor

Output

The following output is an example of BGP summary information, and BGP Summary Field Descriptions describes the fields.

Output Example 
*A:7705_ALU-2>show>router>bgp# summary
===============================================================================
 BGP Router ID : 10.55.55.1        AS : 65000   Local AS : 65000
===============================================================================
BGP Admin State         : Up          BGP Oper State              : Up
Total Peer Groups       : 1           Total Peers                 : 1
Total BGP Paths         : 74          Total Path Memory           : 9128
Total IPv4 Remote Rts   : 600         Total IPv4 Rem. Active Rts  : 563

Total Supressed Rts     : 0           Total Hist. Rts             : 0
Total Decay Rts         : 0

Total VPN Peer Groups   : 0           Total VPN Peers             : 0
Total VPN Local Rts     : 8672
Total VPN-IPv4 Rem. Rts : 8656        Total VPN-IPv4 Rem. Act. Rts: 8656

Total VPN Supp. Rts     : 0           Total VPN Hist. Rts         : 0
Total VPN Decay Rts     : 0
===============================================================================
BGP Summary
===============================================================================
Legend : D - Dynamic Neighbor
===============================================================================
Neighbor
                   AS PktRcvd InQ  Up/Down   State|Rcv/Act/Sent (Addr Family)
                      PktSent OutQ
-------------------------------------------------------------------------------
10.44.10.12
                65000     654    0 04h11m01s 600/563/569 (IPv4)
                          557    0           8656/8656/8672 (VpnIPv4)

10.100.1.3(D)
                65000     21     0 00h06m08s 5/0/7 (IPv4)
                          18     0           2/0/4 (IPv6)
                                             0/0/0 (VpnIPv4)
                                             0/0/0 (VpnIPv6)

===============================================================================
*A:7705_ALU-2>show>router>bgp#

*A:7705_ALU-2>show>router>bgp# summary all
===============================================================================
BGP Summary
===============================================================================
Legend : D - Dynamic Neighbor
===============================================================================
Neighbor
Description 
ServiceId          AS PktRcvd InQ  Up/Down   State|Rcv/Act/Sent (Addr Family)
                      PktSent OutQ
-------------------------------------------------------------------------------
10.44.10.12
Def. Instance   65000     662    0 04h14m52s 600/563/569 (IPv4)
                          564    0           8656/8656/8672 (VpnIPv4)

10.100.1.3(D)
                65000     21     0 00h06m08s 5/0/7 (IPv4)
                          18     0           2/0/4 (IPv6)
                                             0/0/0 (VpnIPv4)
                                             0/0/0 (VpnIPv6)
===============================================================================
*A:7705_ALU-2>show>router>bgp#

*A:7705_ALU-2>show>router>bgp# summary neighbor 10.44.10.12
===============================================================================
BGP Router ID : 10.44.10.1        AS : 65000   Local AS : 65000
===============================================================================
BGP Admin State         : Up          BGP Oper State              : Up
Total Peer Groups       : 1           Total Peers                 : 1
Total BGP Paths         : 74          Total Path Memory           : 9128
Total IPv4 Remote Rts   : 600         Total IPv4 Rem. Active Rts  : 563
Total Supressed Rts     : 0           Total Hist. Rts             : 0
Total Decay Rts         : 0

Total VPN Peer Groups   : 0           Total VPN Peers             : 0
Total VPN Local Rts     : 8672
Total VPN-IPv4 Rem. Rts : 8656        Total VPN-IPv4 Rem. Act. Rts: 8656
Total VPN Supp. Rts     : 0           Total VPN Hist. Rts         : 0
Total VPN Decay Rts     : 0

===============================================================================
BGP Summary
===============================================================================
Legend : D - Dynamic Neighbor
===============================================================================
Neighbor
                   AS PktRcvd InQ  Up/Down   State|Rcv/Act/Sent (Addr Family)
                      PktSent OutQ
-------------------------------------------------------------------------------
10.44.10.12
                65000     673    0 04h20m24s 600/563/569 (IPv4)
                          575    0           8656/8656/8672 (VpnIPv4)
10.100.1.3(D)
                65000     21     0 00h06m08s 5/0/7 (IPv4)
                          18     0           2/0/4 (IPv6)
                                             0/0/0 (VpnIPv4)
                                             0/0/0 (VpnIPv6)
===============================================================================
*A:7705_ALU-2>show>router>bgp#

*A:7705_ALU-2>show>router>bgp# summary family ipv4
===============================================================================
BGP Router ID : 10.44.10.1        AS : 65000   Local AS : 65000
===============================================================================
BGP Admin State         : Up          BGP Oper State              : Up
Total Peer Groups       : 1           Total Peers                 : 1
Total BGP Paths         : 74          Total Path Memory           : 9128
Total IPv4 Remote Rts   : 600         Total IPv4 Rem. Active Rts  : 563

Total Supressed Rts     : 0           Total Hist. Rts             : 0
Total Decay Rts         : 0

Total VPN Peer Groups   : 0           Total VPN Peers             : 0
Total VPN Local Rts     : 8672
Total VPN-IPv4 Rem. Rts : 8656        Total VPN-IPv4 Rem. Act. Rts: 8656

Total VPN Supp. Rts     : 0           Total VPN Hist. Rts         : 0
Total VPN Decay Rts     : 0
===============================================================================
BGP IPv4 Summary
===============================================================================
Legend : D - Dynamic Neighbor
===============================================================================
Neighbor
                   AS PktRcvd PktSent  InQ OutQ Up/Down   State|Recv/Actv/Sent
-------------------------------------------------------------------------------
10.44.10.12
                65000     679     581    0    0 04h23m36s 600/563/569
===============================================================================
*A:7705_ALU-2>show>router>bgp#

*A:7705:Dut-A# show router bgp summary neighbor 10.0.0.3 family ipv6
===============================================================================
BGP Router ID:10.0.0.1         AS:1001        Local AS:1001
===============================================================================
BGP Admin State         : Up          BGP Oper State              : Up
Total IPv4 Remote Rts   : 0           Total IPv4 Rem. Active Rts  : 0
Total McIPv4 Remote Rts : 0           Total McIPv4 Rem. Active Rts: 0
Total IPv6 Remote Rts   : 0           Total IPv6 Rem. Active Rts  : 0
Total IPv4 Backup Rts   : 0           Total IPv6 Backup Rts       : 0

Total VPN-IPv4 Rem. Rts : 0           Total VPN-IPv4 Rem. Act. Rts: 0
Total VPN-IPv6 Rem. Rts : 0           Total VPN-IPv6 Rem. Act. Rts: 0
Total VPN-IPv4 Bkup Rts : 0           Total VPN-IPv6 Bkup Rts     : 0

Total MVPN-IPv4 Rem Rts : 0           Total MVPN-IPv4 Rem Act Rts : 0
Total RouteTgt Rem Rts  : 0           Total RouteTgt Rem Act Rts  : 0
Total EVPN Rem Rts      : 0           Total EVPN Rem Act Rts      : 0
Total LblIpv4 Rem Rts   : 0           Total LblIpv4 Rem. Act Rts  : 0
Total LblIpv6 Rem Rts   : 0           Total LblIpv6 Rem. Act Rts  : 0
Total LblIpv4 Bkp Rts   : 0           Total LblIpv6 Bkp Rts       : 0
Total Link State Rem Rts: 8           Total Link State Rem. Act Rts:0
Bgp-Ls Suppr. Pfxs      : 0           Bgp-Ls Recd. Pfxs            :0
Bgp-Ls Active Pfxs      : 0           Bgp-Ls Rej. Pfxs             :0

===============================================================================
BGP IPv6 Summary
===============================================================================
Legend : D - Dynamic Neighbor
===============================================================================
Neighbor
                   AS PktRcvd PktSent  InQ OutQ Up/Down   State|Recv/Actv/Sent
-------------------------------------------------------------------------------
10.0.0.3
               1000        23      25    0    0 00h03m09s 0/0/0
-------------------------------------------------------------------------------
*A:7705:Dut-A#
Table 15. BGP Summary Field Descriptions

Label

Description

BGP Router ID

The local BGP router ID

AS

The configured autonomous system number

Local AS

The configured local AS setting. If not configured, then the value is the same as the AS.

BGP Admin State

Down: BGP is administratively disabled

Up: BGP is administratively enabled

BGP Oper State

Down: BGP is operationally disabled

Up: BGP is operationally enabled

Total Peer Groups

The total number of configured BGP peer groups

Total Peers

The total number of configured BGP peers

Total BGP Paths

The total number of unique sets of BGP path attributes learned from BGP peers

Total Path Memory

The total amount of memory used to store the path attributes

Total IPv4 Remote Rts

The total number of IPv4 routes learned from BGP peers

Total IPv4 Remote Act. Rts

The total number of IPv4 routes used in the forwarding table

Total Supressed Rts

The total number of suppressed routes due to route damping

Total Hist. Rts

The total number of routes with history due to route damping

Total Decay Rts

The total number of decayed routes due to route damping

Total VPN Peer Groups

The total number of configured VPN peer groups

Total VPN Peers

The total number of configured VPN peers

Total VPN Local Rts

The total number of configured local VPN routes

Total VPN-IPv4 Rem. Rts

The total number of configured remote VPN-IPv4 routes

Total VPN-IPv4 Rem. Act. Rts

The total number of active remote VPN-IPv4 routes used in the forwarding table

Total VPN Supp. Rts

The total number of suppressed VPN routes due to route damping

Total VPN Hist. Rts

The total number of VPN routes with history due to route damping

Total VPN Decay Rts

The total number of decayed routes due to route damping

Total Link State Rem Rts

The total number of link-state routes

Total Link State Rem. Act Rts

The total number of active link-state routes

Bgp-Ls Suppr. Pfxs

The total number of BGP-LS suppressed prefixes

Bgp-Ls Recd. Pfxs

The total number of BGP-LS received prefixes

Bgp-Ls Active Pfxs

The total number of BGP-LS active prefixes

Bgp-Ls Rej. Pfxs

The total number of BGP-LS rejected prefixes

Neighbor

The BGP neighbor address

AS (Neighbor)

The BGP neighbor autonomous system number

PktRcvd

The total number of packets received from the BGP neighbor

PktSent

The total number of packets sent to the BGP neighbor

InQ

The number of BGP messages to be processed

OutQ

The number of BGP messages to be transmitted

Up/Down

The amount of time that the BGP neighbor has either been established or not established depending on its current state

State|Recv/Actv/Sent (Addr Family)

The BGP neighbor’s current state (if not established) or the number of received routes, active routes and sent routes (if established), along with the address family

Clear Commands

flap-statistics
Syntax

flap-statistics [{ip-prefix/mask [neighbor ip-address] | group group-name | regex reg-exp | policy policy-name}]

Context

clear>router>bgp

Description

This command clears route flap statistics.

Parameters
ip-prefix/mask

clears route flap statistics for entries that match the specified IP prefix and mask length

Values

ip-prefix                a.b.c.d  (host bits must be 0)

mask:                     0 to 32

ip-address

clears route flap statistics for entries received from the specified BGP neighbor

Values

ipv4-address:       a.b.c.d

group-name

clears route flap statistics for entries received from any BGP neighbors in the specified peer group

reg-exp

clears route flap statistics for all entries that have the regular expression and the AS path that matches the regular expression

policy-name

clears route flap statistics for entries that match the specified route policy

neighbor
Syntax

neighbor {ip-address | as as-number | external | all} [soft | soft-inbound]

neighbor {ip-address | as as-number | external | all} statistics

neighbor ip-address end-of-rib

Context

clear>router>bgp

Description

This command resets the specified BGP peer or peers. This can cause existing BGP connections to be shut down and restarted.

Parameters
ip-address

resets the BGP neighbor with the specified IP address

Values

ipv4-address:        a.b.c.d

as-number

resets all BGP neighbors with the specified peer AS

Values

1 to 4294967295

external

resets all EBGP neighbors

all

resets all BGP neighbors

soft

the specified BGP neighbors re-evaluate all routes in the Local-RIB against the configured export policies

soft-inbound

the specified BGP neighbors re-evaluate all routes in the RIB-In against the configured import policies

statistics

the BGP neighbor statistics

end-of-rib

clears the routing information base (RIB)

protocol
Syntax

protocol

Context

clear>router>bgp

Description

This command resets the entire BGP protocol.

Debug Commands

events
Syntax

events [neighbor ip-address | group name]

no events

Context

debug>router>bgp

Description

This command logs all events changing the state of a BGP peer.

Parameters
ip-address

debugs only events affecting the specified BGP neighbor

Values

ipv4-address:       a.b.c.d  (host bits must be 0)

name

debugs only events affecting the specified peer group and associated neighbors

graceful-restart
Syntax

graceful-restart [neighbor ip-address | group name]

no graceful-restart

Context

debug>router>bgp

Description

This command enables debugging for BGP graceful restart.

The no form of the command disables the debugging.

Parameters
ip-address

debugs only events affecting the specified BGP neighbor

Values

ipv4-address:       a.b.c.d  (host bits must be 0)

name

debugs only events affecting the specified peer group and associated neighbors

keepalive
Syntax

keepalive [neighbor ip-address | group name]

no keepalive

Context

debug>router>bgp

Description

This command decodes and logs all sent and received Keepalive messages in the debug log.

Parameters
ip-address

debugs only events affecting the specified BGP neighbor

Values

ipv4-address:       a.b.c.d  (host bits must be 0)

name

debugs only events affecting the specified peer group and associated neighbors

notification
Syntax

notification [neighbor ip-address | group name]

no notification

Context

debug>router>bgp

Description

This command decodes and logs all sent and received Notification messages in the debug log.

Parameters
ip-address

debugs only events affecting the specified BGP neighbor

Values

ipv4-address:       a.b.c.d  (host bits must be 0)

name

debugs only events affecting the specified peer group and associated neighbors

open
Syntax

open [neighbor ip-address | group name]

no open

Context

debug>router>bgp

Description

This command decodes and logs all sent and received Open messages in the debug log.

Parameters
ip-address

debugs only events affecting the specified BGP neighbor

name

debugs only events affecting the specified peer group and associated neighbors

outbound-route-filtering
Syntax

 [no] outbound-route-filtering

Context

debug>router>bgp

Description

This command enables debugging for all BGP outbound route filtering (ORF) packets. ORF is used to inform a neighbor of targets (using target-list) that it is willing to receive.

packets
Syntax

packets [neighbor ip-address | group name]

packets

Context

debug>router>bgp

Description

This command decodes and logs all sent and received BGP packets in the debug log.

Parameters
ip-address

debugs only events affecting the specified BGP neighbor

Values

ipv4-address:        a.b.c.d  (host bits must be 0)

name

debugs only events affecting the specified peer group and associated neighbors

route-refresh
Syntax

route-refresh [neighbor ip-address | group name]

no route-refresh

Context

debug>router>bgp

Description

This command enables and disables debugging for BGP route refresh.

Parameters
ip-address

debugs only events affecting the specified BGP neighbor

Values

ipv4-address:       a.b.c.d  (host bits must be 0)

name

debugs only events affecting the specified peer group and associated neighbors

rtm
Syntax

rtm [neighbor ip-address | group name]

no rtm

Context

debug>router>bgp

Description

This command logs RTM changes in the debug log.

Parameters
ip-address

debugs only events affecting the specified BGP neighbor

Values

ipv4-address:        a.b.c.d  (host bits must be 0)

name

debugs only events affecting the specified peer group and associated neighbors

socket
Syntax

socket [neighbor ip-address | group name]

no socket

Context

debug>router>bgp

Description

This command logs all TCP socket events to the debug log.

Parameters
ip-address

debugs only events affecting the specified BGP neighbor

Values

ipv4-address:      a.b.c.d  (host bits must be 0)

name

debugs only events affecting the specified peer group and associated neighbors

timers
Syntax

timers [neighbor ip-address | group name]

no timers

Context

debug>router>bgp

Description

This command logs all BGP timer events to the debug log.

Parameters
ip-address

debugs only events affecting the specified BGP neighbor

Values

ipv4-address:      a.b.c.d  (host bits must be 0)

name

debugs only events affecting the specified peer group and associated neighbors

update
Syntax

update [neighbor ip-address | group name]

no update

Context

debug>router>bgp

Description

This command decodes and logs all sent and received Update messages in the debug log.

Parameters
ip-address

debugs only events affecting the specified BGP neighbor

Values

ipv4-address:      a.b.c.d  (host bits must be 0)

name

debugs only events affecting the specified peer group and associated neighbors