EVPN Interconnect Ethernet Segments in Dual EVPN-VXLAN Instance VPLS Services

This chapter provides information about EVPN Interconnect Ethernet Segments in Dual EVPN-VXLAN Instance VPLS Services.

Topics in this chapter include:

Applicability

The information and configuration in this chapter are based on SR OS Release 21.7.R1. EVPN multi-homing on dual VXLAN instance VPLS services is supported on SR OS Release 19.10.R1, and later.

Overview

Some service providers are deploying large Data Centers (DCs) where SR OS routers are used as leaf switches in a VXLAN fabric. In those cases, all-active multi-homing can provide redundancy and maximize the bandwidth utilization.

SR OS supports Interconnect Ethernet Segments (I-ESs) for VXLAN as per RFC 9014. Chapter EVPN Interconnect Ethernet Segments (I-ESs) describes how I-ESs allow Data Center Gateways (DCGWs) with two BGP instances (one for EVPN-MPLS and one for EVPN-VXLAN) to handle redundancy in VXLAN access networks, as supported in SR OS 15.0.R4, and later.

This chapter describes similar scenarios with EVPN-VXLAN in the core network instead of EVPN-MPLS. The following scenarios are supported with I-ES in VXLAN instance 1:

  • dual instance VPLS with two EVPN-VXLAN instances

  • dual instance VPLS with one EVPN-VXLAN instance and one static VXLAN instance

  • dual instance VPLS with one EVPN-VXLAN instance and one EVPN-MPLS instance

The first two of these scenarios are described in this chapter.

CLI

Sample topology shows VPLS 1 with different EVPN-VXLAN instances: VXLAN instance 1 in DC 1 (and DC2) and VXLAN instance 2 in the WAN.

Figure 1. Sample topology

On DCGW PE-2, the following all-active I-ES is configured for VXLAN instance 1 and service id 1:

# on DCGW PE-2:
configure
    service
        system
            bgp-auto-rd-range 192.0.2.2 comm-val 1 to 1000
            bgp-evpn
                ethernet-segment "I-ES-23_1" virtual create
                    esi 00:23:23:23:23:23:23:00:00:01
                    service-carving
                        mode manual
                        manual
                            preference create
                                value 100
                            exit
                            evi 1
                        exit
                    exit
                    multi-homing all-active
                    network-interconnect-vxlan 1
                    service-id
                        service-range 1
                    exit
                    no shutdown       
                exit
            exit

The following command configures VPLS 1 with dual EVPN-VXLAN instance. VXLAN instance 1 is a member of the I-ES and VXLAN instance 2 is configured with mh-mode network and auto-disc-route-advertisement:

# on DCGW PE-2:
configure
    service
        vpls 1 name "VPLS 1" customer 1 create
            vxlan instance 1 vni 11 create
                rx-discard-on-ndf bum
            exit
            vxlan instance 2 vni 12 create
            exit
            bgp
                route-distinguisher auto-rd
                route-target export target:64500:11 import target:64500:11
            exit
            bgp 2
                route-distinguisher auto-rd
                route-target export target:64500:12 import target:64500:12
            exit
            bgp-evpn
                evi 1
                vxlan bgp 1 vxlan-instance 1
                    ecmp 2
                    default-route-tag 11
                    auto-disc-route-advertisement
                    no shutdown
                exit
                vxlan bgp 2 vxlan-instance 2
                    ecmp 2
                    default-route-tag 12
                    auto-disc-route-advertisement
                    mh-mode network
                    no shutdown
                exit
            exit
            stp
                shutdown
            exit
            sap 1/2/1:1 create
                no shutdown
            exit
            no shutdown
        exit

By default, the multi-homing mode for EVPN-VXLAN is access, but for VXLAN instance 2, it is modified to mh-mode network. The following error is raised when attempting to configure VXLAN instance 1—as a member of an I-ES—with mh-mode network:

*A:PE-2>config>service>vpls>bgp-evpn>vxlan# mh-mode network
MINOR: SVCMGR #7886 cannot modify evpn - not supported when vxlan instance is a member of an ethernet-segment

With mh-mode network configured, it is mandatory to configure auto-disc-route-advertisement; for mh-mode access, it is optional. When auto-disc-route-advertisement is enabled in an access instance associated to an I-ES, AD per-ES/EVI routes and MAC/IP routes are advertised for the I-ES.

The following AD per-EVI route is sent by DCGW PE-2:

13 2021/09/07 14:35:47.456 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 81
    Flag: 0x90 Type: 14 Len: 36 Multiprotocol Reachable NLRI:
        Address Family EVPN
        NextHop len 4 NextHop 192.0.2.2
        Type: EVPN-AD Len: 25 RD: 192.0.2.2:1 ESI: 00:23:23:23:23:23:23:00:00:01,
                      tag: 0 Label: 11 (Raw Label: 0xb) PathId:
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 16 Len: 24 Extended Community:
        origin:64500:23
        target:64500:11
        bgp-tunnel-encap:VXLAN
"

For MAC routes and their ESI value for an access VXLAN instance, the following redistribution considerations apply.

  • With mh-mode access and auto-disc-route-advertisement configured, MAC routes are redistributed from the instance network to the instance access with the I-ESI if present, regardless of the original ESI.

  • With mh-mode access and no auto-disc-route-advertisement, MAC routes are redistributed with zero ESI, regardless of the original ESI.

The following EVPN-MAC route is sent by DCGW PE-2 with I-ESI 00:23:23:23:23:23:23:00:00:01 of "I-ES-23_1":

79 2021/09/07 14:36:18.380 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 89
    Flag: 0x90 Type: 14 Len: 44 Multiprotocol Reachable NLRI:
        Address Family EVPN
        NextHop len 4 NextHop 192.0.2.2
        Type: EVPN-MAC Len: 33 RD: 192.0.2.2:1 ESI: 00:23:23:23:23:23:23:00:00:01,
         tag: 0, mac len: 48 mac: 00:ca:fe:ca:fe:05, IP len: 0, IP: NULL, label1: 11
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 16 Len: 24 Extended Community:
        origin:64500:23
        target:64500:11
        bgp-tunnel-encap:VXLAN
"

The following ES route is sent by DCGW PE-2:

17 2021/09/07 14:35:47.456 UTC MINOR: DEBUG #2001 Base Peer 1: 192.0.2.1
"Peer 1: 192.0.2.1: UPDATE
Peer 1: 192.0.2.1 - Send BGP UPDATE:
    Withdrawn Length = 0
    Total Path Attr Length = 71
    Flag: 0x90 Type: 14 Len: 34 Multiprotocol Reachable NLRI:
        Address Family EVPN
        NextHop len 4 NextHop 192.0.2.2
        Type: EVPN-ETH-SEG Len: 23 RD: 192.0.2.2:0
              ESI: 00:23:23:23:23:23:23:00:00:01, IP-Len: 4 Orig-IP-Addr: 192.0.2.2 
    Flag: 0x40 Type: 1 Len: 1 Origin: 0
    Flag: 0x40 Type: 2 Len: 0 AS Path:
    Flag: 0x40 Type: 5 Len: 4 Local Preference: 100
    Flag: 0xc0 Type: 16 Len: 16 Extended Community:
        df-election::DF-Type:Preference/DP:0/DF-Preference:100/AC:1
        target:23:23:23:23:23:23
"

The following commands are not supported when mh-mode network is configured:

  • proxy-arp/nd

  • assisted replication

  • source-vtep-security

Attempting to enable these unsupported commands while a BGP-EVPN VXLAN instance has mh-mode network triggers error messages, as follows:

*A:PE-2>config>service>vpls# proxy-arp
MINOR: SVCMGR #8005 Cannot create proxy arp - not supported when a bgp-evpn vxlan instance has mh-mode network
*A:PE-2>config>service>vpls# proxy-nd
MINOR: SVCMGR #8008 Cannot create proxy nd - not supported when a bgp-evpn vxlan instance has mh-mode network
*A:PE-2>config>service>vpls>vxlan# assisted-replication replicator
MINOR: SVCMGR #8111 Cannot change assisted-replicated role - not supported when vxlan instance is in use by bgp-evpn with mh-mode network
*A:PE-2>config>service>vpls>vxlan# source-vtep-security
MINOR: SVCMGR #7897 Cannot modify vxlan instance - not supported when vxlan instance is in use by bgp-evpn with mh-mode network

Local bias

When EVPN-VXLAN is used in the instance network of a dual-instance VPLS service, local bias—as described in RFC 8365—is used for split horizon in all-active I-ESs. In VXLAN, there is no multicast label or multicast BMAC, so BUM traffic is identified by the MAC destination address. The modified forwarding rules for the I-ES-sourced BUM traffic for ingress PE and egress PE are as follows:

  • ingress PE

    • The Non-Designated Forwarder (NDF) must discard BUM traffic, so one of the following two commands must be configured in VXLAN instance 1.

      • no send-imet-ir-on-ndf

      • rx-discard-on-ndf bum

    • BUM frames received on any SAP or I-ES VXLAN binding are flooded to:

      • local non-ES and single-active DF ES SAPs

      • local all-active ES SAPs (DF and NDF)

      • EVPN-VXLAN destinations (BUM frames received on an I-ES VXLAN binding follow SHG rules, so they can only be forwarded to EVPN-VXLAN destinations belonging to the other VXLAN instance.)

  • egress PE

    • Look up source VTEP for BUM frames received on EVPN-VXLAN.

      • If the source VTEP matches a PE with which the local PE shares an ES and a VXLAN service, then the local PE does not forward to the shared local ESs (this includes port, lag, and network-interconnect-VXLAN ESs).

      • The local PE forwards to local ESs that are not shared but only when in DF state.

EVPN-VXLAN network interconnect VXLAN multi-homing and local bias shows the BUM forwarding with local bias procedures in multi-instance VPLS services.

Figure 2. EVPN-VXLAN network interconnect VXLAN multi-homing and local bias

In the example, GW1 and GW2 are configured with no send-imet-ir-on-ndf. TOR1 generates BUM traffic that will only reach DF GW1 and is forwarded as follows.

  • Ingress PE GW1 forwards to CE-1 and EVPN-VXLAN destinations GW2, GW3, and GW4.

  • Egress PE GW2 identifies the source VTEP as a PE with which I-ES-1 is shared, so it does not forward the BUM frames to the local I-ES. PE GW2 forwards only to the non-shared ES and local SAPs, in this case, to CE-2.

  • Egress PE GW3 receives the BUM traffic with a source VTEP that does not match any PE with which GW3 shares an ES, so it forwards to all ESs that are DF, in this case, to CE-3.

  • Egress PE GW4 receives the BUM traffic with a source VTEP that does not match any PE with which GW4 shares an ES, so it forwards to all ESs that are DF, in this case, to TOR2 through I-ES-2.

Local bias with static VXLAN on I-ES

When a static VXLAN instance coexists with an EVPN-VXLAN instance in the same VPLS service, traffic blackholes may occur when the static VXLAN instance is associated to an all-active I-ES. This is because, when multi-homing is used with an EVPN-VXLAN network instance, the NDF PE always discards unknown unicast traffic to the static VXLAN instance (this is not the case with EVPN-MPLS if the unknown traffic has a BUM label).

All-active I-ES NDF PE-5 drops unknown unicast traffic shows the packet blackhole for unknown unicast traffic at all-active I-ES NDF PE-5.

Figure 3. All-active I-ES NDF PE-5 drops unknown unicast traffic

In the event that the remote PE-1 has learned the destination MAC address MAC6 via I-ES-45 EVPN destination, but the DCGWs PE-4 and PE-5 do not know MAC6, regular aliasing procedures allow that PE-1 sends unicast traffic with destination MAC6 to the NDF PE-5, which does not know MAC6 and drops all unknown unicast traffic, creating a blackhole for the flow.

When a static VXLAN instance coexists with an EVPN-VXLAN instance in the same VPLS service, Nokia recommends using a single-active I-ES or an anycast solution without I-ES instead of an all-active I-ES.

Configuration

Sample topology shows the sample topology with six SR OS nodes:

Figure 4. Sample topology

The initial configuration includes:

  • Cards, MDAs, and ports

  • Router interfaces

  • IS-IS on all interfaces (level 1 in the DCs; level 2 in the WAN)

BGP is configured for the EVPN address family. PE-1 acts as Route Reflector (RR) in DC 1 and PE-6 as RR in DC 2; no RR is used in the WAN.

The BGP configuration on RR PE-1 in DC 1 is as follows. The BGP configuration on RR PE-6 in DC2 is similar.

# on PE-1:
configure
    router Base
        autonomous-system 64500
        bgp
            family evpn
            vpn-apply-import
            vpn-apply-export
            cluster 192.0.2.1
            rapid-withdrawal
            rapid-update evpn
            group "DC"
                type internal
                neighbor 192.0.2.2
                exit
                neighbor 192.0.2.3
                exit
            exit

On DCGWs PE-2 and PE-3, BGP is configured as follows. The policies are explained in the next section.

# on PE-2, PE-3:
configure
    router Base
        autonomous-system 64500
        bgp
            family evpn
            vpn-apply-import
            vpn-apply-export
            rapid-withdrawal
            rapid-update evpn
            group "DC"
                type internal
                import "drop SOO-DCGW-23"
                export "export DC routes and add SOO"
                neighbor 192.0.2.1
                exit
            exit
            group "WAN"
                type internal
                export "export WAN routes only"
                neighbor 192.0.2.4
                exit
                neighbor 192.0.2.5
                exit
            exit

On DCGWs PE-4 and PE-5, BGP is configured as follows. The policies are explained in the next section.

# on PE-4, PE-5:
configure
    router
        autonomous-system 64500
        bgp
            family evpn
            vpn-apply-import
            vpn-apply-export
            rapid-withdrawal
            rapid-update evpn
            group "DC"
                type internal
                import "drop SOO-DCGW-45"
                export "export DC routes and add SOO"
                neighbor 192.0.2.6
                exit
            exit
            group "WAN"
                type internal
                export "export WAN routes only"
                neighbor 192.0.2.2
                exit
                neighbor 192.0.2.3
                exit
            exit

The following examples are configured:

All-active multi-homing I-ESs in dual EVPN-VXLAN instance VPLS

All-active multi-homing for I-ESs shows the example topology with the service VPLS 1 on all nodes and two all-active I-ESs:

Figure 5. All-active multi-homing for I-ESs

On PE-1, VPLS 1 is configured as follows. The configuration on PE-6 is similar.

# on PE-1:
configure
    service
        system
            bgp-auto-rd-range 192.0.2.1 comm-val 1 to 1000     # on PE-6: 192.0.2.6
        exit
        vpls 1 name "VPLS 1" customer 1 create
            vxlan instance 1 vni 11 create
            exit
            bgp
                route-distinguisher auto-rd
                route-target export target:64500:11 import target:64500:11
            exit
            bgp-evpn
                evi 1
                vxlan bgp 1 vxlan-instance 1
                    ecmp 2
                    no shutdown
                exit
            exit
            sap 1/2/1:1 create
            exit
            no shutdown
        exit

On DCGW PE-2, the following all-active multi-homing I-ES is configured for VXLAN instance 1 and service id 1. The configuration on DCGW PE-3 is similar, but the preference value is 150 instead of 100.

# on PE-2:
configure
    service
        system
            bgp-evpn
                ethernet-segment "I-ES-23_1" virtual create
                    esi 00:23:23:23:23:23:23:00:00:01
                    service-carving
                        mode manual
                        manual
                            preference create
                                value 100            # on PE-3: preference value 150
                            exit
                            evi 1
                        exit
                    exit
                    multi-homing all-active
                    network-interconnect-vxlan 1
                    service-id
                        service-range 1
                    exit
                    no shutdown
                exit
            exit

On DCGWs PE-4 and PE-5, the following I-ES is configured:

# on PE-4, PE-5:
configure
    service
        system
            bgp-evpn
                ethernet-segment "I-ES-45_1" virtual create
                    esi 00:45:45:45:45:45:45:00:00:01
                    service-carving
                        mode auto
                    exit
                    multi-homing all-active
                    network-interconnect-vxlan 1
                    service-id
                        service-range 1
                    exit
                    no shutdown       
                exit
            exit
        exit

On DCGWs PE-2, PE-3, PE-4, and PE-5, VPLS 1 is configured as follows. The rx-discard-on-ndf bum command makes the NDF drop any BUM traffic in VXLAN instance 1. VXLAN instance 2 is configured with mh-mode network and auto-disc-route-advertisement.

# on PE-2, PE-3, PE-4, PE-5:
configure
    service
        vpls 1 name "VPLS 1" customer 1 create
            vxlan instance 1 vni 11 create
                rx-discard-on-ndf bum
            exit
            vxlan instance 2 vni 12 create
            exit
            bgp
                route-distinguisher auto-rd
                route-target export target:64500:11 import target:64500:11
            exit
            bgp 2
                route-distinguisher auto-rd
                route-target export target:64500:12 import target:64500:12
            exit
            bgp-evpn
                evi 1
                vxlan bgp 1 vxlan-instance 1
                    ecmp 2
                    default-route-tag 11
                    auto-disc-route-advertisement
                    no shutdown
                exit
                vxlan bgp 2 vxlan-instance 2
                    ecmp 2
                    default-route-tag 12
                    auto-disc-route-advertisement
                    mh-mode network
                    no shutdown
                exit
            exit
            stp
                shutdown
            exit
            sap 1/2/1:1 create
                no shutdown
            exit
            no shutdown
        exit

On PE-2 and PE-3, the following policies are configured.

  • The import policy "drop SOO-DCGW-23" in group "DC" is used to drop all VXLAN instance 1 routes between PE-2 and PE-3.

  • The export policy "export WAN routes only" in group "WAN" is applied to avoid sending VXLAN instance 1 routes to the WAN PEs.

  • The export policy "export DC routes and add SOO" in group "DC" is used to tag VXLAN instance 1 routes with community "SOO-23".

# on PE-2, PE-3:
configure
    router Base
        policy-options
            begin
            community "SOO-23" 
                members "origin:64500:23"
            exit
            policy-statement "drop SOO-DCGW-23"         # import in group "DC"
                entry 10
                    from
                        community "SOO-23"
                        family evpn
                    exit
                    action drop
                    exit
                exit
                default-action accept
                exit
            exit
            policy-statement "export WAN routes only"   # export in group "WAN"
                entry 10
                    from
                        tag 11
                        family evpn
                    exit
                    action drop
                    exit
                exit
                default-action accept
                exit
            exit
            policy-statement "export DC routes and add SOO"   # export in group "DC"
                entry 10
                    from
                        tag 11  
                        family evpn
                    exit
                    action accept
                        community add "SOO-23"
                    exit
                exit
                default-action accept
                exit
            exit
            commit

On PE-4 and PE-5, the following policies are configured:

# on PE-4, PE-5:
configure
    router Base
        policy-options
            begin
            community "SOO-45" 
                members "origin:64500:45"
            exit
            policy-statement "drop SOO-DCGW-45"         # import in group "DC"
                entry 10
                    from
                        community "SOO-45"
                        family evpn
                    exit
                    action drop
                    exit
                exit
                default-action accept
                exit
            exit
            policy-statement "export WAN routes only"   # export in group "WAN"
                entry 10
                    from
                        tag 11
                        family evpn
                    exit
                    action drop
                    exit
                exit
                default-action accept
                exit
            exit
            policy-statement "export DC routes and add SOO"   # export in group "DC"
                entry 10
                    from
                        tag 11  
                        family evpn
                    exit
                    action accept
                        community add "SOO-45"
                    exit
                exit
                default-action accept
                exit
            exit
            commit

For VPLS 1, PE-2 is DF and PE-3 is NDF in the I-ES "I-ES-23_1":

*A:PE-2# show service id 1 ethernet-segment
No sap entries
No sdp entries
 
===============================================================================
VXLAN Ethernet-Segment Information
===============================================================================
VXLAN Instance        Eth-Seg                          Status
-------------------------------------------------------------------------------
1                     I-ES-23_1                        DF
===============================================================================
*A:PE-3# show service id 1 ethernet-segment
No sap entries
No sdp entries
 
===============================================================================
VXLAN Ethernet-Segment Information
===============================================================================
VXLAN Instance        Eth-Seg                          Status
-------------------------------------------------------------------------------
1                     I-ES-23_1                        NDF
===============================================================================

PE-4 is NDF and PE-5 is DF in the I-ES "I-ES-45_1":

*A:PE-4# show service vxlan-instance-using ethernet-segment
 
===============================================================================
VXLAN Ethernet-Segment Information
===============================================================================
SvcId       VXLAN Instance      ES Name                          Status
-------------------------------------------------------------------------------
1           1                   I-ES-45_1                        NDF
===============================================================================
*A:PE-5# show service vxlan-instance-using ethernet-segment
 
===============================================================================
VXLAN Ethernet-Segment Information
===============================================================================
SvcId       VXLAN Instance      ES Name                          Status
-------------------------------------------------------------------------------
1           1                   I-ES-45_1                        DF
===============================================================================

On leaf PE-1, the VXLAN destinations in VXLAN instance 1 are the following:

*A:PE-1# show service id 1 vxlan destinations 
===============================================================================
Egress VTEP, VNI
===============================================================================
Instance    VTEP Address                            Egress VNI  EvpnStatic Num
 Mcast       Oper State                              L2 PBR     SupBcasDom MACs
-------------------------------------------------------------------------------
1           192.0.2.2                               11          evpn       0
 BUM         Up                                      No          No        
1           192.0.2.3                               11          evpn       0
 BUM         Up                                      No          No        
-------------------------------------------------------------------------------
Number of Egress VTEP, VNI : 2
-------------------------------------------------------------------------------
===============================================================================
===============================================================================
BGP EVPN-VXLAN Ethernet Segment Dest
===============================================================================
Instance  Eth SegId                       Num. Macs     Last Change
-------------------------------------------------------------------------------
1         00:23:23:23:23:23:23:00:00:01   5             09/07/2021 14:35:57
-------------------------------------------------------------------------------
Number of entries: 1
-------------------------------------------------------------------------------
===============================================================================

On DCGW PE-2, the VXLAN destinations in VXLAN instances 1 and 2 are the following:

*A:PE-2# show service id 1 vxlan destinations
 
===============================================================================
Egress VTEP, VNI
===============================================================================
Instance    VTEP Address                            Egress VNI  EvpnStatic Num
 Mcast       Oper State                              L2 PBR     SupBcasDom MACs
-------------------------------------------------------------------------------
1           192.0.2.1                               11          evpn       1
 BUM         Up                                      No          No
2           192.0.2.3                               12          evpn       1
 BUM         Up                                      No          No
2           192.0.2.4                               12          evpn       1
 BUM         Up                                      No          No
2           192.0.2.5                               12          evpn       1
 BUM         Up                                      No          No
-------------------------------------------------------------------------------
Number of Egress VTEP, VNI : 4
-------------------------------------------------------------------------------
===============================================================================
 
===============================================================================
BGP EVPN-VXLAN Ethernet Segment Dest
===============================================================================
Instance  Eth SegId                       Num. Macs     Last Change
-------------------------------------------------------------------------------
2         00:45:45:45:45:45:45:00:00:01   1             09/07/2021 14:36:31
-------------------------------------------------------------------------------
Number of entries: 1
-------------------------------------------------------------------------------
===============================================================================

ECMP 2 is configured, so aliasing is used. PE-1 can reach the I-ES "I-ES-23_1" in VXLAN instance 1 via PE-2 and PE-3:

*A:PE-1# show service id 1 vxlan esi 00:23:23:23:23:23:23:00:00:01
 
===============================================================================
BGP EVPN-VXLAN Ethernet Segment Dest
===============================================================================
Instance  Eth SegId                       Num. Macs     Last Change
-------------------------------------------------------------------------------
1         00:23:23:23:23:23:23:00:00:01   5             09/07/2021 14:35:57
-------------------------------------------------------------------------------
Number of entries: 1
-------------------------------------------------------------------------------
===============================================================================
 
===============================================================================
BGP EVPN-VXLAN Dest TEP Info
===============================================================================
Instance  TEP Address                   Egr VNI             Last Change
-------------------------------------------------------------------------------
1         192.0.2.2                     11                  09/07/2021 14:35:47
1         192.0.2.3                     11                  09/07/2021 14:35:57
-------------------------------------------------------------------------------
Number of entries : 2
-------------------------------------------------------------------------------
===============================================================================

In a similar way, PE-4 can reach the I-ES "I-ES-23_1" via PE-2 and PE-3 in VXLAN instance 2:

*A:PE-4# show service id 1 vxlan esi 00:23:23:23:23:23:23:00:00:01
 
===============================================================================
BGP EVPN-VXLAN Ethernet Segment Dest
===============================================================================
Instance  Eth SegId                       Num. Macs     Last Change
-------------------------------------------------------------------------------
2         00:23:23:23:23:23:23:00:00:01   1             09/07/2021 14:36:10
-------------------------------------------------------------------------------
Number of entries: 1
-------------------------------------------------------------------------------
===============================================================================
 
===============================================================================
BGP EVPN-VXLAN Dest TEP Info
===============================================================================
Instance  TEP Address                   Egr VNI             Last Change
-------------------------------------------------------------------------------
2         192.0.2.2                     12                  09/07/2021 14:36:10
2         192.0.2.3                     12                  09/07/2021 14:36:10
-------------------------------------------------------------------------------
Number of entries : 2
-------------------------------------------------------------------------------
===============================================================================

The following command on PE-2 shows the ES information for "I-ES-23_1": DF status, DF candidate list, VXLAN instance service range, and so on:

*A:PE-2# show service system bgp-evpn ethernet-segment name "I-ES-23_1" all
 
===============================================================================
Service Ethernet Segment
===============================================================================
Name                    : I-ES-23_1
Eth Seg Type            : Virtual
Admin State             : Enabled            Oper State         : Up
ESI                     : 00:23:23:23:23:23:23:00:00:01
Oper ESI                : 00:23:23:23:23:23:23:00:00:01
Auto-ESI Type           : None
AC DF Capability        : Include
Multi-homing            : allActive          Oper Multi-homing  : allActive
ES SHG Label            : 524287
Source BMAC LSB         : None
VXLAN Instance Id       : 1
ES Activation Timer     : 3 secs (default)
Oper Group              : (Not Specified)
Svc Carving             : manual             Oper Svc Carving   : manual
Cfg Range Type          : lowest-pref
 
-------------------------------------------------------------------------------
DF Pref Election Information
-------------------------------------------------------------------------------
Preference     Preference     Last Admin Change        Oper Pref      Do No
Mode           Value                                   Value          Preempt
-------------------------------------------------------------------------------
revertive      100            09/07/2021 14:35:47      100            Disabled
-------------------------------------------------------------------------------
 
-------------------------------------------------------------------------------
EVI Ranges
-------------------------------------------------------------------------------
From                                    To
-------------------------------------------------------------------------------
1                                       1
-------------------------------------------------------------------------------
ISID Ranges: <none>
===============================================================================
 
===============================================================================
EVI Information
===============================================================================
EVI                 SvcId               Actv Timer Rem      DF
-------------------------------------------------------------------------------
1                   1                   0                   yes
-------------------------------------------------------------------------------
Number of entries: 1
===============================================================================
 
-------------------------------------------------------------------------------
DF Candidate list
-------------------------------------------------------------------------------
EVI                                     DF Address
-------------------------------------------------------------------------------
1                                       192.0.2.2
1                                       192.0.2.3
-------------------------------------------------------------------------------
Number of entries: 2
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
 
===============================================================================
 
---snip---
 
===============================================================================
Vxlan Instance Service Ranges
===============================================================================
Svc Range Start          Svc Range End            Last Changed
-------------------------------------------------------------------------------
1                        1                        09/07/2021 14:35:47
-------------------------------------------------------------------------------
Number of Entries: 1
===============================================================================

When traffic is sent between CE-1 and CE-6, the EVPN-MAC routes are sent with I-ESI. The FDB for VPLS 1 on PE-1 shows I-ESI 00:23:23:23:23:23:23:00:00:01 of "I-ES-23_1" as source identifier for MAC address 00:ca:fe:ca:fe:06 of CE-6:

*A:PE-1# show service id 1 fdb detail
 
===============================================================================
Forwarding Database, Service 1
===============================================================================
ServId     MAC               Source-Identifier       Type     Last Change
            Transport:Tnl-Id                         Age
-------------------------------------------------------------------------------
1          00:ca:fe:ca:fe:01 sap:1/2/1:1             L/127    09/07/21 14:48:43
1          00:ca:fe:ca:fe:06 eES:                    Evpn     09/07/21 14:48:43
                             00:23:23:23:23:23:23:00:00:01
-------------------------------------------------------------------------------
No. of MAC Entries: 2
-------------------------------------------------------------------------------
Legend:  L=Learned O=Oam P=Protected-MAC C=Conditional S=Static Lf=Leaf
===============================================================================

On PE-2, the FDB for VPLS 1 shows I-ESI 00:45:45:45:45:45:45:00:00:01 of "I-ES-45_1" as source identifier for MAC address 00:ca:fe:ca:fe:06 of CE-6:

*A:PE-2# show service id 1 fdb detail
 
===============================================================================
Forwarding Database, Service 1
===============================================================================
ServId     MAC               Source-Identifier       Type     Last Change
            Transport:Tnl-Id                         Age
-------------------------------------------------------------------------------
1          00:ca:fe:ca:fe:01 vxlan-1:                Evpn     09/07/21 14:48:43
                             192.0.2.1:11
1          00:ca:fe:ca:fe:06 eES:                    Evpn     09/07/21 14:48:43
                             00:45:45:45:45:45:45:00:00:01
-------------------------------------------------------------------------------
No. of MAC Entries: 2
-------------------------------------------------------------------------------
Legend:  L=Learned O=Oam P=Protected-MAC C=Conditional S=Static Lf=Leaf
===============================================================================

Single-active multi-homing I-ES when static VXLAN coexists with EVPN-VXLAN in the same VPLS

I-ES with EVPN-VXLAN in DC 1 and static VXLAN in DC2 shows the sample topology for VPLS 2 with static VXLAN in DC 2 and the single-active "I-ES-45_2" on PE-4 and PE-5.

Figure 6. I-ES with EVPN-VXLAN in DC 1 and static VXLAN in DC2

The configuration for VPLS 2 on PE-1, PE-2, and PE-3 is similar to the configuration for VPLS 1, so only the configuration on PE-4, PE-5, and PE-6 is shown.

On PE-6, VPLS 2 is configured with static VXLAN using non-anycast VTEP addresses:

# on PE-6:
configure
    service
        system
            bgp-auto-rd-range 192.0.2.6 comm-val 1 to 1000
        exit
        vpls 2 name "VPLS 2" customer 1 create
            vxlan instance 1 vni 21 create
                egr-vtep 192.0.2.4 create
                exit
                egr-vtep 192.0.2.5 create
                exit
            exit
            sap 1/2/1:2 create
                no shutdown
            exit
            no shutdown
        exit

To avoid blackholes, the I-ES between DCGWs PE-4 and PE-5 must not be all-active.

On PE-4 and PE-5, the single-active I-ES "I-ES-45_2" is configured as follows:

# on PE-4, PE-5:
configure
    service
        system
            bgp-evpn
                ethernet-segment "I-ES-45_2" virtual create
                    esi 00:45:45:45:45:45:45:00:00:02
                    service-carving
                        mode auto
                    exit
                    multi-homing single-active
                    network-interconnect-vxlan 1
                    service-id
                        service-range 2
                    exit
                    no shutdown       
                exit
            exit

On PE-4 and PE-5, VPLS 2 is configured as follows:

# on PE-4, PE-5:
configure
    service
       vpls 2 name "VPLS 2" customer 1 create
            vxlan instance 1 vni 21 create
                egr-vtep 192.0.2.6 create
                exit
            exit
            vxlan instance 2 vni 22 create
            exit
            bgp 2
                route-distinguisher auto-rd
                route-target export target:64500:22 import target:64500:22
            exit
            bgp-evpn
                evi 2
                vxlan bgp 2 vxlan-instance 2
                    ecmp 2
                    default-route-tag 22
                    auto-disc-route-advertisement
                    mh-mode network
                    no shutdown
                exit
            exit
            stp
                shutdown
            exit
            sap 1/2/1:2 create        # optional SAP toward local CE
                no shutdown
            exit
            no shutdown
        exit

The policies on all DCGWs must be modified with tag 21 for VXLAN instance 1 in VPLS 2, as follows:

# on PE-2, PE-3:
configure
    router Base
        policy-options
            begin
            policy-statement "export WAN routes only"
                entry 20
                    from
                        tag 21
                        family evpn
                    exit
                    action drop
                    exit
                exit
                default-action accept
                exit
            exit
            policy-statement "export DC routes and add SOO"
                entry 20
                    from
                        tag 21
                        family evpn
                    exit
                    action accept
                        community add "SOO-23"
                    exit
                exit
                default-action accept
                exit
            exit
            commit

DCGW PE-5 is NDF for "I-ES-45_2":

*A:PE-5# show service id 2 ethernet-segment 
No sap entries
No sdp entries
 
===============================================================================
VXLAN Ethernet-Segment Information
===============================================================================
VXLAN Instance        Eth-Seg                          Status
-------------------------------------------------------------------------------
1                     I-ES-45_2                        NDF
===============================================================================

On PE-5, the status of VXLAN instance 1 in VPLS 2 is mhStandby, as follows:

*A:PE-5# show service id 2 vxlan 
===============================================================================
VPLS VXLAN
===============================================================================
Vxlan Src Vtep IP: N/A
 
===============================================================================
Vxlan Instance 
===============================================================================
VXLAN Instance                VNI         AR          Oper-flags   VTEP
                                                                   security
-------------------------------------------------------------------------------
1                             21          none        mhStandby    disabled
2                             22          none        none         disabled
-------------------------------------------------------------------------------
Number of Entries : 2
-------------------------------------------------------------------------------
===============================================================================

The VXLAN destinations in VPLS 2 on PE-5 are the following:

*A:PE-5# show service id 2 vxlan destinations 
 
===============================================================================
Egress VTEP, VNI
===============================================================================
Instance    VTEP Address                            Egress VNI  EvpnStatic Num
 Mcast       Oper State                              L2 PBR     SupBcasDom MACs
-------------------------------------------------------------------------------
1           192.0.2.6                               21          static     0
 -           Up                                      No          No        
2           192.0.2.2                               22          evpn       1
 BUM         Up                                      No          No        
2           192.0.2.3                               22          evpn       1
 BUM         Up                                      No          No        
2           192.0.2.4                               22          evpn       1
 BUM         Up                                      No          No        
-------------------------------------------------------------------------------
Number of Egress VTEP, VNI : 4
-------------------------------------------------------------------------------
===============================================================================
 
===============================================================================
BGP EVPN-VXLAN Ethernet Segment Dest
===============================================================================
Instance  Eth SegId                       Num. Macs     Last Change
-------------------------------------------------------------------------------
2         00:23:23:23:23:23:23:00:00:02   1             09/07/2021 14:53:05
-------------------------------------------------------------------------------
Number of entries: 1
-------------------------------------------------------------------------------
===============================================================================
Note:

An anycast solution without I-ES can also be configured when an EVPN-VXLAN coexists with a static VXLAN.

Conclusion

Service providers can use I-ESs for better bandwidth utilization and redundancy in large DCs. EVPN all-active multi-homing I-ESs can be used in dual EVPN-VXLAN instance VPLS services. However, when a static VXLAN instance coexists with EVPN-VXLAN in the same VPLS, a single-active multi-homing I-ES (or an anycast solution without I-ES) is required to avoid blackholes.