ESM SLAAC Prefix Assignment via Local Address Server
This chapter provides information about ESM SLAAC prefix assignment via local address server.
Topics in this chapter include:
Applicability
The information and configuration in this chapter was based on SR OS Release 13.0.R1. The CLI in the current edition is SR OS Release 16.0.R7 based. Both Internet Protocol over Ethernet (IPoE) and Point-to-Point Protocol over Ethernet (PPPoE) are supported.
Overview
Triple Play Service Delivery Architecture (TPSDA) supports IPv6 address/prefix assignment through Dynamic Host Configuration Protocol (DHCP), Point-to-Point Protocol (PPP), and Stateless Address Auto-Configuration (SLAAC). This chapter provides configuration examples of SLAAC prefix assignment via the local address server.
The network topology shown in TPSDA Network Topology shows a TPSDA setup. The setup consists of a 7750 SR serving as a Broadband Network Gateway (BNG). The 7450 is used as a Layer 2 switch aggregating all subscriber traffic.
There are two methods available for subscriber SLAAC prefix assignment. The first method, not covered in this chapter, is to pre-define a static SLAAC prefix for each subscriber on the BNG, in a Local User Database (LUDB) or via a RADIUS AAA server. With such a configuration, the database would contain hundreds of thousands of /64 SLAAC prefixes, each with their associated host. Every time a subscriber moved to a new location (a new subnet), the allocation of a new prefix within the new subnet would be required, along with a manual update of the database.
The second method, covered in this chapter, is to simplify SLAAC prefix assignment. A local address server is configured to dynamically assign SLAAC prefixes to hosts. Only a SLAAC pool name is obtained from RADIUS or LUDB after a successful subscriber authentication. This pool name is then used to assign a SLAAC prefix to the subscriber, out of the named address pool.
Using a local pool for SLAAC prefix assignment provides the following advantages:
-
Reduces the configuration required on the RADIUS server, the local user database (LUDB), and the BNG to a few lines;
-
Removes the complexity of managing actual prefixes in a database;
-
Reduces configuration errors; for example, accidentally assigning the same prefix to two different subscribers.
The local address server already has tools, logs, and monitoring features for prefix management, such as prefix depletion and subnet migration. Service providers can rely on the local address server to assist in SLAAC prefix assignment.
Configuration
This guide assumes a basic knowledge of ESM.
Different Types of SLAAC Hosts
SLAAC is supported for both PPP and IP over Ethernet hosts. The local address server can be enabled for either or both host types on a group interface level.
PPP SLAAC Hosts
PPP IPv4 hosts rely on IPCP to retrieve an IPv4 address. However, IPv6CP does not assign IPv6 addresses or prefixes to the host. PPP hosts rely on router solicitations (RSs) or DHCPv6 to obtain IPv6 addresses/prefixes.
PPP SLAAC hosts creation requires three configuration steps.
Step 1. Following is a baseline PPP subscriber management configuration on the BNG.
# on BNG-1
configure
service
ies 1 customer 1 create
subscriber-interface "sub-int-1" create
ipv6
subscriber-prefixes
prefix 2001:db8::/32 wan-host
exit
exit
group-interface "group-int-1" create
ipv6
router-advertisements
prefix-options
autonomous
exit
no shutdown
exit
exit
sap 1/1/1:1 create
sub-sla-mgmt
def-sub-id use-sap-id
def-sub-profile "sub-profile-1"
def-sla-profile "sla-profile-1"
sub-ident-policy "sub-ident-policy-1"
multi-sub-sap 10
no shutdown
exit
exit
pppoe
no shutdown
exit
exit
exit
exit
Step 2. A DHCPv6 server is used as the local address server to assign SLAAC prefixes. It is possible to reuse the same pool for both DHCPv6 and SLAAC address/prefix assignment. For SLAAC hosts, the keyword wan-host is required.
# on BNG-1
configure
router
dhcp6
local-dhcp-server "dhcp6-server-1" create
use-pool-from-client
pool "pool-v6-1" create
prefix 2001:db8::/32 wan-host create
exit
exit
no shutdown
exit
exit
Step 3. On the PPP group interface, configure the local address server. Specify that the local address server is to be used for client application ppp-slaac. The server name must match the name configured for the DHCPv6 server (step 2). The DHCPv6 server is reused as the local address server.
# on a/BNG1
configure
service
ies 1
subscriber-interface "sub-int-1" create
group-interface "group-int-1" create
local-address-assignment
ipv6
client-application ppp-slaac ipoe-slaac
server "dhcp6-server-1"
exit
no shutdown
exit
exit
exit
exit
There are two options for supplying a SLAAC pool name for a PPP host: RADIUS and LUDB.
Option 1: During PPP authentication, RADIUS can return the SLAAC pool name attribute along with other subscriber attributes. Note: Remove the user-db configuration from pppoe when using RADIUS authentication. Add an authentication policy to the group interface to enable RADIUS authentication.
# on a/BNG1
configure
service
ies 1
subscriber-interface "sub-int-1" create
group-interface "group-int-1" create
authentication-policy "auth-policy-1"
exit
exit
exit
Then, add the attribute Alc-SLAAC-IPv6-Pool to the RADIUS user database. The following is an example from a freeradius clients file.
user_ppp_01 Auth-Type := CHAP, Cleartext-Password := password
Alc-SLA-Prof-Str = "sla-profile-1",
Alc-Subsc-ID-Str = "home-ppp-1",
Alc-Subsc-Prof-Str = "sub-profile-1",
Alc-SLAAC-IPv6-Pool = pool-v6-1,
Alc-PPP-Force-IPv6CP = 1
Option 2: During PPP authentication, an LUDB can return the SLAAC pool name attribute along with other subscriber attributes. Note: Remove the authentication policy from the group interface when using LUDB.
First, create an LUDB and add a user to the LUDB. This LUDB is configured with a default host for all PPPoE hosts and returns a default SLAAC pool name.
# on a/BNG1
configure
subscriber-mgmt
local-user-db "pppoe-ludb-lookup" create
ppp
match-list username
host "default" create
ipv6-slaac-prefix-pool "pool-v6-1"
no shutdown
exit
exit
no shutdown
exit
exit
exit
Then, refer to this LUDB from the group interface.
# on a/BNG1
configure
service
ies 1
subscriber-interface "sub-int-1" create
group-interface "group-int-1" create
pppoe
user-db "pppoe-ludb-lookup"
no shutdown
exit
exit
exit
exit
With the preceding configuration, this group interface supports SLAAC prefix assignment through the local address pool. The following is the result of a PPP host being assigned a SLAAC prefix by the local address server.
*A:BNG-1# show service active-subscribers hierarchy
===============================================================================
Active Subscribers Hierarchy
===============================================================================
-- 1/1/1:1 (sub-profile-1)
|
+-- sap:1/1/1:1 - sla:sla-profile-1
|
+-- PPP-session - mac:00:00:00:11:11:11 - sid:1 - svc:1
| circuit-id:circuit1
|
+-- 2001:db8::/64 - SLAAC
-------------------------------------------------------------------------------
Number of active subscribers : 1
Flags: (N) = the host or the managed route is in non-forwarding state
===============================================================================
*A:BNG-1#
In the show pppoe session, the IPv6 prefix is from the local address pool and the pool name is from authentication (RADIUS or LUDB).
*A:BNG-1# show service id 1 pppoe session detail
===============================================================================
PPPoE sessions for svc-id 1
===============================================================================
Sap Id Mac Address Sid Up Time Type
IP/L2TP-Id/Interface-Id MC-Stdby
-------------------------------------------------------------------------------
1/1/1:1 00:00:00:11:11:11 1 0d 00:02:29 local
02:00:00:FF:FE:11:11:11
LCP State : Opened
IPCP State : Closed
IPv6CP State : Opened
PPP MTU : 1492
PPP Auth-Protocol : CHAP
PPP User-Name : sub@domain
Subscriber-interface : sub-int-1
Group-interface : group-int-1
IP Origin : none
DNS Origin : none
NBNS Origin : none
Subscriber : "1/1/1:1"
Sub-Profile-String : ""
SLA-Profile-String : ""
SPI group ID : (Not Specified)
ANCP-String : ""
Int-Dest-Id : ""
App-Profile-String : ""
Category-Map-Name : ""
Acct-Session-Id : "0217FF0000000C5CB82FA7"
Sap-Session-Index : 1
IP Address : N/A
Primary DNS : N/A
Secondary DNS : N/A
Primary NBNS : N/A
Secondary NBNS : N/A
Address-Pool : N/A
IPv6 Prefix : 2001:db8::/64
IPv6 Prefix Origin : local-pool
IPv6 Prefix Pool : "pool-v6-1"
IPv6 Del.Pfx. : N/A
IPv6 Del.Pfx. Origin : none
IPv6 Del.Pfx. Pool : ""
IPv6 Address : N/A
IPv6 Address Origin : none
IPv6 Address Pool : ""
Primary IPv6 DNS : N/A
Secondary IPv6 DNS : N/A
Router adv. policy : N/A
Ignoring DF bit : false
Radius sub-if prefix : N/A
Circuit-Id : circuit1
Remote-Id :
Radius Session-TO : N/A
Radius Class :
Radius User-Name : sub@domain
Logical-Line-Id :
Service-Name :
-------------------------------------------------------------------------------
Number of sessions : 1
===============================================================================
*A:BNG-1#
ICMP6 debugging can be used to show the SLAAC address assignment process.
debug
router
ip
icmp6
exit
exit
43 2019/04/18 10:04:55.642 CEST MINOR: DEBUG #2001 Base TIP
"TIP: ICMP6_PKT
ICMP6 egressing on group-int-1 (Base):
fe80::17:ffff:fe00:0 -> ff02::1
Type: Router Advertisement (134)
Code: No Code (0)
Hop Limit : 64
Flags :
Retrans Time : 0
Def Life Time : 4500
Reachable Time: 0
Option : Prefix : 2001:db8::/64
Flags : On Link Autoconfig
Valid Life Time: 86400
Pref Life Time: 3600
"
IPoE SLAAC Hosts
IPoE offers two methods to create an SLAAC host:
-
Triggered by a successful IPv4 host creation
-
Triggered by an RS request
SLAAC Host Creation via IPv4 Host
A successful IPv4 host creation can subsequently trigger the creation of a SLAAC host; this is known as IPoE-linking. The SLAAC prefix for the host must be provided through either RADIUS or LUDB during the IPv4 host authentication.
IPoE SLAAC host creation through IPoE linking requires four steps.
Step 1. Following is a baseline IPoE subscriber management configuration on the BNG.
# on BNG-1
configure
service
ies 1 customer 1 create
description "BNG-1"
subscriber-interface "sub-int-1" create
address 10.255.255.253/8
ipv6
subscriber-prefixes
prefix 2001:db8::/32 wan-host
exit
exit
group-interface "group-int-1" create
dhcp
server 192.168.0.1
lease-populate 10
client-applications dhcp
gi-address 10.255.255.253
no shutdown
exit
ipv6
router-advertisements
prefix-options
autonomous
exit
no shutdown
exit
exit
sap 1/1/1:1 create
sub-sla-mgmt
def-sub-id use-sap-id
---snip---
multi-sub-sap 10
no shutdown
exit
exit
exit
exit
Step 2. Enable IPoE-linking to allow SLAAC host creation after a successful IPv4 host creation. Several options should be enabled for the SLAAC host to function. Gratuitous router advertisement will send unsolicited router advertisements with a SLAAC prefix for the host to use. The BNG uses the gratuitous router advertisement to let the subscriber know the assigned prefix to auto-configure. In this case, where prefixes are dynamically assigned, the subscriber will not know the prefix ahead of time, so the gratuitous router advertisement must be enabled. Shared-circuit-id will allow the SLAAC host to use the same circuit ID as the IPv4 host.
# on BNG-1
configure
service
ies 1
subscriber-interface "sub-int-1"
group-interface "group-int-1"
ipoe-linking
shared-circuit-id
gratuitous-rtr-adv
no shutdown
exit
Step 3. As with PPP hosts, the DHCPv6 server is reused as the local address server for SLAAC prefix assignment. It is possible to reuse the same pool for both DHCPv6 and SLAAC subscribers. For SLAAC hosts, the keyword wan-host is required. In this case, an IPv4 host must be created first to trigger the creation of the IPv6 SLAAC host. The following example uses the local DHCPv4 server for IPv4 address assignment, but it is possible to use other methods for IPv4 address assignment, such as through LUDB and RADIUS proxy.
configure
router
dhcp
local-dhcp-server "dhcp-server-1" create
use-gi-address scope pool
pool "pool-v4-1" create
subnet 10.0.0.0/8 create
options
subnet-mask 255.0.0.0
default-router 10.255.255.253
exit
address-range 10.0.0.10 10.0.0.254
exit
exit
no shutdown
exit
exit
dhcp6
local-dhcp-server "dhcp6-server-1" create
use-pool-from-client
pool "pool-v6-1" create
prefix 2001:db8::/32 wan-host create
exit
exit
no shutdown
exit
exit
exit
exit
Step 4. On the group interface, configure the local address server. Specify that the local address-server is to be used for client application ipoe-slaac. The server name must match the name configured for the DHCPv6 server (Step 3). The local address server reuses the local DHCPv6 server.
configure
service
ies 1
subscriber-interface "sub-int-1" create
group-interface "group-int-1" create
local-address-assignment
ipv6
client-application ipoe-slaac
server "dhcp6-server-1"
exit
no shutdown
exit
There are two options for supplying a SLAAC pool name for the DHCPv4 host: RADIUS and LUDB.
Option 1: During authentication, RADIUS can return the SLAAC pool name attribute along with other subscriber attributes. Note: Remove the user-db configuration from the DHCP and IPOE-session context when using RADIUS authentication. First, add an authentication policy to the group interface to allow RADIUS authentication.
# on a/BNG1
configure
service
ies 1
subscriber-interface "sub-int-1" create
group-interface "group-int-1" create
authentication-policy "auth-policy-1"
exit
exit
exit
Then, add the attribute Alc-SLAAC-IPv6-Pool to the subscriber host RADIUS user database. The following is an example using the client file on freeradius.
00:00:10:10:12:13 Cleartext-Password := password
Alc-SLA-Prof-Str = "sla-profile-1",
Alc-Subsc-ID-Str = "home-ipoe-1",
Alc-Subsc-Prof-Str = "sub-profile-1",
Alc-SLAAC-IPv6-Pool = pool-v6-1
Option 2: During authentication, LUDB can return the SLAAC pool name attribute along with other subscriber attributes. Note: Remove the authentication policy from the group interface when using LUDB.
First, create an LUDB and add a user in the LUDB. This LUDB is configured with a default host for all DHCPv4 hosts and returns a default SLAAC pool name.
# on a/BNG1
configure
subscriber-mgmt
local-user-db "ipoe-ludb-lookup" create
ipoe
match-list sap-id
host "default" create
ipv6-slaac-prefix-pool "pool-v6-1"
no shutdown
exit
exit
no shutdown
exit
exit
exit
Then, refer to this LUDB from the group interface. The LUDB can be referred to in two places.
Nokia recommends that IPoE subscribers use an IPoE session. In this case, the LUDB is referenced from the group interface ipoe-session context.
# on a/BNG1
configure
service
ies 1
subscriber-interface "sub-int-1" create
group-interface "group-int-1" create
ipoe-session
user-db "ipoe-ludb-lookup"
no shutdown
exit
exit
exit
exit
For operators that do not use IPoE sessions (not recommended), the LUDB is referenced from the group interface dhcp context.
# on a/BNG1
configure
service
ies 1
subscriber-interface "sub-int-1" create
group-interface "group-int-1" create
dhcp
user-db "ipoe-ludb-lookup"
no shutdown
exit
exit
exit
exit
With the preceding configuration, the local address server on the group interface is ready to assign SLAAC prefixes. Start a DHCPv4 session to the group interface SAP.
*A:BNG-1# show service active-subscribers hierarchy
===============================================================================
Active Subscribers Hierarchy
===============================================================================
-- 1/1/1:1 (sub-profile-1)
|
+-- sap:1/1/1:1 - sla:sla-profile-1
|
+-- IPOE-session - mac:00:00:00:22:22:22 - svc:1
|
|-- 10.0.0.10 - DHCP
|
+-- 2001:db8::/64 - SLAAC
-------------------------------------------------------------------------------
Number of active subscribers : 1
Flags: (N) = the host or the managed route is in non-forwarding state
===============================================================================
*A:BNG-1#
In the show ipoe session, the IPv6 prefix origin is from the local address pool and the pool name is from authentication (RADIUS or LUDB).
*A:BNG-1# show service id 1 ipoe session detail
===============================================================================
IPoE sessions for service 1
===============================================================================
SAP : 1/1/1:1
Mac Address : 00:00:00:22:22:22
Circuit-Id : 11
Remote-Id : AA
Session Key : sap-mac
MC-Standby : No
Subscriber-interface : sub-int-1
Group-interface : group-int-1
Termination Type : local
Up Time : 0d 00:07:55
Session Time Left : N/A
Last Auth Time : 04/18/2019 10:45:43
Min Auth Intvl (left) : infinite (N/A)
Persistence Key : N/A
Subscriber : "1/1/1:1"
Sub-Profile-String : ""
SLA-Profile-String : ""
SPI group ID : (Not Specified)
ANCP-String : ""
Int-Dest-Id : ""
App-Profile-String : ""
Category-Map-Name : ""
Acct-Session-Id : "0217FF000000215CB83937"
Sap-Session-Index : 1
IP Address : 10.0.0.10/8
IP Origin : DHCP
Primary DNS : N/A
Secondary DNS : N/A
Primary NBNS : N/A
Secondary NBNS : N/A
Address-Pool : N/A
IPv6 Prefix : 2001:db8::/64
IPv6 Prefix Origin : LclPool
IPv6 Prefix Pool : "pool-v6-1"
IPv6 Del.Pfx. : N/A
IPv6 Del.Pfx. Origin : None
IPv6 Del.Pfx. Pool : ""
IPv6 Address : N/A
IPv6 Address Origin : None
IPv6 Address Pool : ""
Primary IPv6 DNS : N/A
Secondary IPv6 DNS : N/A
Router adv. policy : N/A
Radius sub-if prefix : N/A
Radius Session-TO : N/A
Radius Class :
Radius User-Name :
GTP IMSI :
GTP APN : (Not Specified)
-------------------------------------------------------------------------------
Number of sessions : 1
===============================================================================
*A:BNG-1#
ICMP6 debugging can be used to show the SLAAC address assignment process.
debug
router
ip
icmp6
exit
exit
exit
63 2019/04/18 10:45:44.212 CEST MINOR: DEBUG #2001 Base TIP
"TIP: ICMP6_PKT
ICMP6 egressing on group-int-1 (Base):
fe80::17:ffff:fe00:0 -> ff02::1
Type: Router Advertisement (134)
Code: No Code (0)
Hop Limit : 64
Flags :
Retrans Time : 0
Def Life Time : 4500
Reachable Time: 0
Option : Src Link Layer Addr 02:17:01:01:00:01
Option : Prefix : 2001:db8::/64
Flags : On Link Autoconfig
Valid Life Time: 86400
Pref Life Time: 3600
"
SLAAC Host Creation via RS Trigger
An IPv6 SLAAC host can be created through a host router originated solicit message, which removes the dependency of a SLAAC host on successful DHCPv4 host creation.
SLAAC hosts creation via RS trigger requires four configuration steps.
Step 1. The following is a baseline IPoE subscriber management configuration on the BNG.
# on BNG-1
configure
service
ies 1
description "BNG-1"
subscriber-interface "sub-int-1" create
ipv6
subscriber-prefixes
prefix 2001:db8::/32 pd wan-host
exit
exit
group-interface "group-int-1" create
ipv6
router-advertisements
prefix-options
autonomous
exit
no shutdown
exit
exit
sap 1/1/1:1 create
sub-sla-mgmt
def-sub-id use-sap-id
def-sub-profile "sub-profile-1"
def-sla-profile "sla-profile-1"
sub-ident-policy "sub-ident-policy-1"
multi-sub-sap 10
no shutdown
exit
exit
exit
exit
exit
Step 2. Enable the group interface to process router solicit messages. There are a few options available for router solicit triggered hosts. The inactivity timer will remove the host if the global unique address of the host is not learned through Neighbor Solicitation (NS), Router Solicitation (RS), or Duplicate Address Detection (DAD) messages within the time specified. The min-auth-interval is the interval that a subscriber must wait before the next router-solicit messages is used for re-authentication. Re-authentication can occur if the first RS was lost, or the BNG/RADIUS system was queued up with requests.
# on a/BNG1
configure
service
ies 1
subscriber-interface "sub-int-1" create
group-interface "group-int-1" create
ipv6
router-solicit
inactivity-timer min 5
min-auth-interval min 5
user-db "ipoe-ludb-lookup"
no shutdown
exit
Step 3. A DHCPv6 server is used as the local address server for SLAAC prefix assignment. It is possible to reuse the same pool for both DHCPv6 and SLAAC subscribers. For SLAAC hosts, the keyword wan-host is required.
# on BNG-1
configure
router
dhcp6
local-dhcp-server "dhcp6-server-1" create
use-pool-from-client
pool "pool-v6-1" create
prefix 2001:db8::/32 wan-host create
exit
exit
no shutdown
exit
exit
Step 4. On the group interface, configure the local address server. Specify that the local address server is to be used for client application ipoe-slaac. The server name must match the name configured for the DHCPv6 server. The local address server reuses the local DHCPv6 server.
# on BNG-1
configure
service
ies 1 customer 1 create
subscriber-interface "sub-int-1" create
group-interface "group-int-1" create
local-address-assignment
ipv6
client-application ppp-slaac ipoe-slaac
server "dhcp6-server-1"
exit
no shutdown
exit
exit
There are two options for supplying the SLAAC pool name for the DHCPv4 host: RADIUS and LUDB.
Option 1: During authentication, RADIUS can return the SLAAC pool name attribute along with other subscriber attributes. Note: Remove the user-db configuration from the router-solicit and ipoe-session when using RADIUS authentication. First, add an authentication policy to the group interface to allow RADIUS authentication.
# on a/BNG1
configure
service
ies 1
subscriber-interface "sub-int-1" create
group-interface "group-int-1" create
authentication-policy "auth-policy-1"
exit
Then, add the attribute Alc-SLAAC-IPv6-Pool to the subscriber host RADIUS user database.
00:00:10:10:12:13 Cleartext-Password := password
Alc-SLA-Prof-Str = "sla-profile-1",
Alc-Subsc-ID-Str = "home-ipoe-1",
Alc-Subsc-Prof-Str = "sub-profile-1",
Alc-SLAAC-IPv6-Pool = pool-v6-1,
Option 2: During authentication, LUDB can return the SLAAC pool name attribute along with other subscriber attributes. Note: Remove the authentication policy from the group interface when using LUDB.
First, create an LUDB and add a user in the LUDB. The LUDB configures a default host for all SLAAC hosts and returns a default SLAAC pool name.
# on BNG-1
configure
subscriber-mgmt
local-user-db "ipoe-ludb-lookup" create
ipoe
match-list sap-id
host "default" create
ipv6-slaac-prefix-pool "pool-v6-1"
no shutdown
exit
exit
no shutdown
exit
exit
exit
Then, refer to this LUDB from the group interface. The LUDB can be referred to in two places.
Nokia recommends that IPoE subscribers use an IPoE session. In this case, the LUDB is referenced from the group interface ipoe-session context.
# on BNG-1
configure
service
ies 1
subscriber-interface "sub-int-1" create
group-interface "group-int-1" create
ipoe-session
user-db "ipoe-ludb-lookup"
no shutdown
exit
exit
exit
exit
For operators that do not enable IPoE sessions on the BNG (not recommended), the LUDB can be referred to from the group interface in the router-solicit context.
# on a/BNG1
configure
service
ies 1
subscriber-interface "sub-int-1" create
group-interface "group-int-1" create
ipv6
router-solicit
user-db "ipoe-ludb-lookup"
no shutdown
exit
exit
exit
exit
exit
With the preceding configuration, the group interface is ready to assign SLAAC prefixes from the local address pool. Let the host trigger a router solicit packet.
*A:BNG-1# show service active-subscribers hierarchy
===============================================================================
Active Subscribers Hierarchy
===============================================================================
-- 1/1/1:1 (sub-profile-1)
|
+-- sap:1/1/1:1 - sla:sla-profile-1
|
+-- IPOE-session - mac:00:00:00:33:33:33 - svc:1
|
+-- 2001:db8::/64 - SLAAC
-------------------------------------------------------------------------------
Number of active subscribers : 1
Flags: (N) = the host or the managed route is in non-forwarding state
===============================================================================
*A:BNG-1#
In the show ipoe session, the IPv6 prefix is from the local address pool and the pool name is from authentication (RADIUS or LUDB).
*A:BNG-1# show service id 1 ipoe session detail
===============================================================================
IPoE sessions for service 1
===============================================================================
SAP : 1/1/1:1
Mac Address : 00:00:00:33:33:33
Circuit-Id :
Remote-Id :
Session Key : sap-mac
MC-Standby : No
Subscriber-interface : sub-int-1
Group-interface : group-int-1
Termination Type : local
Up Time : 0d 00:02:21
Session Time Left : N/A
Last Auth Time : 04/18/2019 11:07:52
Min Auth Intvl (left) : infinite (N/A)
Persistence Key : N/A
Subscriber : "1/1/1:1"
Sub-Profile-String : ""
SLA-Profile-String : ""
SPI group ID : (Not Specified)
ANCP-String : ""
Int-Dest-Id : ""
App-Profile-String : ""
Category-Map-Name : ""
Acct-Session-Id : "0217FF000000255CB83E67"
Sap-Session-Index : 1
IP Address : N/A
IP Origin : None
Primary DNS : N/A
Secondary DNS : N/A
Primary NBNS : N/A
Secondary NBNS : N/A
Address-Pool : N/A
IPv6 Prefix : 2001:db8::/64
IPv6 Prefix Origin : LclPool
IPv6 Prefix Pool : "pool-v6-1"
IPv6 Del.Pfx. : N/A
IPv6 Del.Pfx. Origin : None
IPv6 Del.Pfx. Pool : ""
IPv6 Address : N/A
IPv6 Address Origin : None
IPv6 Address Pool : ""
Primary IPv6 DNS : N/A
Secondary IPv6 DNS : N/A
Router adv. policy : N/A
Radius sub-if prefix : N/A
Radius Session-TO : N/A
Radius Class :
Radius User-Name :
GTP IMSI :
GTP APN : (Not Specified)
-------------------------------------------------------------------------------
Number of sessions : 1
===============================================================================
*A:BNG-1#
ICMP6 debugging can be used to show the SLAAC address assignment process.
debug
router
ip
icmp6
exit
exit
exit
71 2019/04/18 11:07:52.372 CEST MINOR: DEBUG #2001 Base TIP
"TIP: ICMP6_PKT
ICMP6 egressing on group-int-1 (Base):
fe80::17:ffff:fe00:0 -> ff02::1
Type: Router Advertisement (134)
Code: No Code (0)
Hop Limit : 64
Flags :
Retrans Time : 0
Def Life Time : 4500
Reachable Time: 0
Option : Src Link Layer Addr 02:17:01:01:00:01
Option : Prefix : 2001:db8::/64
Flags : On Link Autoconfig
Valid Life Time: 86400
Pref Life Time: 3600
"
Conclusion
7750 SR TPSDA offers a variety of address assignment options such as PPP, DHCPv4, DHCPv6, and SLAAC. These options allow service providers to pick the address assignment scheme that best fits their networks. SLAAC address assignment is an essential IPv6 address assignment protocol. Having to assign a static prefix per subscriber host in advance could be a challenge for operators. This chapter provides a complete configuration example of using the local address server to assign prefixes dynamically to IPoE and PPPoE subscriber hosts. This efficient way to assign SLAAC prefixes to subscribers enables operators to achieve a faster time to market for new IPv6 services.