Segment Routing v6 Configuration Guide for Cisco 8000 Series Routers, Cisco IOS XR Releases

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Segment Routing v6 Configuration Guide for Cisco 8000 Series Routers, Cisco IOS XR Releases

IPv6 L3VPN services over SRv6 networks

Updated: September 8, 2026

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Explains how BGP signals service SIDs for IPv6 L3VPNs and provides the restrictions, configuration, and verification needed to transport VPN traffic across an SRv6 core.

IPv6 L3VPN is an SRv6 L3 service that

  • provides IPv6 Layer 3 Virtual Private Networks (VPNv6) over an SRv6 network

  • enables egress Provider Edge (PE) routers to signal an SRv6 SID with the BGP overlay service route, and

  • allows ingress PEs to encapsulate IPv4/IPv6 payloads in an outer IPv6 header, using the SRv6 service SID as the destination address.

Table 1. Feature History Table

Feature Name

Release Information

Feature Description

SRv6 Services: IPv6 L3VPN

 Release 25.4.1

Introduced in this release on: Fixed Systems (8010 [ASIC: A100])(select variants only*)

*This feature is supported on:

  • 8011-32Y8L2H2FH

  • 8011-12G12X4Y-A/D

SRv6 Services: IPv6 L3VPN

 Release 25.1.1

Introduced in this release on: Fixed Systems (8700 [ASIC: K100], 8010 [ASIC: A100])

This feature is now supported on:

  • 8712-MOD-M

  • 8011-4G24Y4H-I

SRv6 Services: IPv6 L3VPN

Release 7.8.1

With this feature, the egress PE can signal an SRv6 Service SID with the BGP overlay service route. The ingress PE encapsulates the IPv4/IPv6 payload in an outer IPv6 header where the destination address is the SRv6 Service SID provided by the egress PE. BGP messages between PEs carry SRv6 Service SIDs to interconnect PEs and form VPNs.

Restrictions of SRv6-based IPv6 L3VPN

SRv6 locator assignment and allocation guidelines

  • SRv6 locator can be assigned globally, for all VRFs, for an individual VRF, or per-prefix.

  • Per-VRF allocation mode is supported (uDT6 behavior)

  • Per-VRF-46 allocation mode is supported (uDT46 behavior)

Supported Network Capabilities

  • Dual-Stack L3VPN Services (IPv4, IPv6) are supported

  • Equal-Cost Multi-path (ECMP) and Unequal Cost Multipath (UCMP) are supported.

  • BGP (iBGP, eBGP), OSPF, Static are supported as PE-CE protocol.

  • BGP route leaking between BGP Global and L3VPN is supported.

  • MPLS L3VPN and SRv6 L3VPN interworking gateway is supported.

  • Per-CE allocation mode is not supported (uDX6 behavior)

Configure SRv6-based IPv6 L3VPN

To enable SRv6-based L3VPN in BGP, you must activate SRv6, specify the locator, and set the SID allocation mode. SRv6 locators can be assigned at the service, address-family, or global BGP level, with inheritance rules determining which locator is used for SID allocation.

SRv6 locators can be assigned at different levels inside the BGP routing process. BGP allocates SRv6 Service SIDs from configured locator spaces according to the following inheritance rules:

  1. Use the locator as defined under the service.

    If not defined under the specific service, then:

  2. Use the locator as defined under the corresponding address-family.

    If not defined under the corresponding address-family, then:

  3. Use the locator as defined globally under BGP.

Procedure

  1. Enable SRv6-based L3VPN by activating SRv6 under BGP.

    Specify the appropriate SRv6 locator, and configure the SID allocation mode according to your network requirements.

    • Use Case 1: Assign SRv6 locator globally.

      This example shows how to configure the SRv6 locator name under BGP global:

      Node1(config)# router bgp 100
Node1(config-bgp)# segment-routing srv6
Node1(config-bgp-gbl-srv6)# locator Node1-locator
Node1(config-bgp-gbl-srv6)# exit
Node1(config-bgp)# address-family vpnv6 unicast
Node1(config-bgp-af)# exit
Node1(config-bgp)# neighbor 3001::12:1:1:4
Node1(config-bgp-nbr)# remote-as 100
Node1(config-bgp-nbr)# address-family vpnv6 unicast
Node1(config-bgp-nbr-af)# exit
Node1(config-bgp-nbr)# exit
Node1(config-bgp)# vrf vrf_cust6
Node1(config-bgp-vrf)# rd 100:6
Node1(config-bgp-vrf)# address-family ipv6 unicast
Node1(config-bgp-vrf-af)# commit
    • Use Case 2: Assign SRv6 locator for all VRFs.

      This example shows how to configure the SRv6 locator for all VRFs under VPNv6 Address Family, with per-VRF label allocation mode:

      Node1(config)# router bgp 100
Node1(config-bgp)# address-family vpnv6 unicast
Node1(config-bgp-af)# vrf all
Node1(config-bgp-af-vrfall)# segment-routing srv6
Node1(config-bgp-af-vrfall-srv6)# locator Node1-locator
Node1(config-bgp-af-vrfall-srv6)# alloc mode per-vrf
Node1(config-bgp-af-vrfall-srv6)# exit
Node1(config-bgp-af-vrfall)# exit
Node1(config-bgp-af)# exit
Node1(config-bgp)# neighbor 3001::12:1:1:4
Node1(config-bgp-nbr)# remote-as 100
Node1(config-bgp-nbr)# address-family vpnv6 unicast
Node1(config-bgp-nbr-af)# exit
Node1(config-bgp-nbr)# exit
Node1(config-bgp)# vrf vrf_cust6
Node1(config-bgp-vrf)# rd 100:6
Node1(config-bgp-vrf)# address-family ipv6 unicast
Node1(config-bgp-vrf-af)# commit

      This example shows how to configure the SRv6 locator for all VRFs under VPNv4/v6 address family, with per-VRF-46 label allocation mode:

      Node1(config)# router bgp 200
Node1(config-bgp)# address-family vpnv4 unicast
Node1(config-bgp-af)# vrf all
Node1(config-bgp-af-vrfall)# segment-routing srv6
Node1(config-bgp-af-vrfall-srv6)# locator Node1-locator
Node1(config-bgp-af-vrfall-srv6)# alloc mode per-vrf-46
Node1(config-bgp-af-vrfall-srv6)# exit
Node1(config-bgp-af-vrfall)# exit
Node1(config-bgp-af)# exit
Node1(config-bgp)# address-family vpnv6 unicast
Node1(config-bgp-af)# vrf all
Node1(config-bgp-af-vrfall)# segment-routing srv6
Node1(config-bgp-af-vrfall-srv6)# locator Node1-locator
Node1(config-bgp-af-vrfall-srv6)# alloc mode per-vrf-46
Node1(config-bgp-af-vrfall-srv6)# exit
Node1(config-bgp-af-vrfall)# exit
Node1(config-bgp-af)# exit
Node1(config-bgp)# neighbor 3001::12:1:1:4
Node1(config-bgp-nbr)# remote-as 100
Node1(config-bgp-nbr)# address-family vpnv6 unicast
Node1(config-bgp-nbr-af)# exit
Node1(config-bgp-nbr)# exit
Node1(config-bgp)# vrf vrf_cust6
Node1(config-bgp-vrf)# rd 100:6
Node1(config-bgp-vrf)# address-family ipv6 unicast
Node1(config-bgp-vrf-af)# commit
    • Use Case 3: Assign SRv6 locator for a specific VRF.

      This example shows how to configure the SRv6 locator for an individual VRF, with per-VRF label allocation mode:

      Node1(config)# router bgp 100
Node1(config-bgp)# address-family vpnv6 unicast
Node1(config-bgp-af)# exit
Node1(config-bgp)# neighbor 3001::12:1:1:4
Node1(config-bgp-nbr)# remote-as 100
Node1(config-bgp-nbr)# address-family vpnv6 unicast
Node1(config-bgp-nbr-af)# exit
Node1(config-bgp-nbr)# exit
Node1(config-bgp)# vrf vrf_cust6
Node1(config-bgp-vrf)# rd 100:6
Node1(config-bgp-vrf)# address-family ipv6 unicast
Node1(config-bgp-vrf-af)# segment-routing srv6
Node1(config-bgp-vrf-af-srv6)# locator Node1-locator
Node1(config-bgp-vrf-af-srv6)# alloc mode per-vrf
Node1(config-bgp-vrf-af-srv6)# commit

      This example shows how to configure the SRv6 locator for an individual VRF, for both IPv4 and IPv6 address families, with per-VRF-46 label allocation mode:

      Node1(config)# router bgp 200
Node1(config-bgp)# address-family vpnv6 unicast
Node1(config-bgp-af)# exit
Node1(config-bgp)# neighbor 3001::12:1:1:4
Node1(config-bgp-nbr)# remote-as 100
Node1(config-bgp-nbr)# address-family vpnv6 unicast
Node1(config-bgp-nbr-af)# exit
Node1(config-bgp-nbr)# exit
Node1(config-bgp)# vrf vrf_cust6
Node1(config-bgp-vrf)# rd 100:6
Node1(config-bgp-vrf)# address-family ipv4 unicast
Node1(config-bgp-vrf-af)# segment-routing srv6
Node1(config-bgp-vrf-af-srv6)# locator Node1-locator
Node1(config-bgp-vrf-af-srv6)# alloc mode per-vrf-46
Node1(config-bgp-vrf-af-srv6)# exit
Node1(config-bgp-vrf-af)# exit
Node1(config-bgp-vrf)# address-family ipv6 unicast
Node1(config-bgp-vrf-af)# segment-routing srv6
Node1(config-bgp-vrf-af-srv6)# locator Node1-locator
Node1(config-bgp-vrf-af-srv6)# alloc mode per-vrf-46
Node1(config-bgp-vrf-af-srv6)# commit

      This example shows how to configure the SRv6 locator for an Individual VRF, with per-CE label allocation mode:

      Node1(config)# router bgp 100
Node1(config-bgp)# address-family vpnv6 unicast
Node1(config-bgp-af)# exit
Node1(config-bgp)# neighbor 3001::12:1:1:4
Node1(config-bgp-nbr)# remote-as 100
Node1(config-bgp-nbr)# address-family vpnv6 unicast
Node1(config-bgp-nbr-af)# exit
Node1(config-bgp-nbr)# exit
Node1(config-bgp)# vrf vrf_cust6
Node1(config-bgp-vrf)# rd 100:6
Node1(config-bgp-vrf)# address-family ipv6 unicast
Node1(config-bgp-vrf-af)# segment-routing srv6
Node1(config-bgp-vrf-af-srv6)# locator Node1-locator
Node1(config-bgp-vrf-af-srv6)# alloc mode per-ce
Node1(config-bgp-vrf-af-srv6)# commit

  2. Verify that the local and received SIDs have been correctly allocated under VPNv6 and specific VRF (vrf_cust6).

    Example:

    Node1# show bgp vpnv6 unicast local-sids 

BGP router identifier 10.1.1.1, local AS number 1
BGP generic scan interval 60 secs
Non-stop routing is enabled
BGP table state: Active
Table ID: 0x0   RD version: 0
BGP main routing table version 50
BGP NSR Initial initsync version 18 (Reached)
BGP NSR/ISSU Sync-Group versions 0/0
BGP scan interval 60 secs

Status codes: s suppressed, d damped, h history, * valid, > best
              i - internal, r RIB-failure, S stale, N Nexthop-discard
Origin codes: i - IGP, e - EGP, ? - incomplete
   Network            Local Sid                                   Alloc mode   Locator
Route Distinguisher: 8:8
*>i3008::8:8:8:8/128  NO SRv6 Sid                                 -            -
* i                   NO SRv6 Sid                                 -            -
Route Distinguisher: 100:6 (default for vrf vrf_cust6)
*> 3001::1:1:1:1/128  fc00:0:1:40::                               per-vrf      locator1
*> 3001::2:2:2:2/128  fc00:8:1:40::                               per-vrf      locator2
*> 3001::3:3:3:3/128  fc00:9:1:40::                               per-vrf      locator4
*> 3001::4:4:4:4/128  fc00:9:1:41::                               per-ce       locator4
*> 3001::5:5:5:5/128  NO SRv6 Sid                                 -            -
*> 3001::12:1:1:5/128 NO SRv6 Sid                                 -            -
*>i3008::8:8:8:8/128  NO SRv6 Sid                                 -            -


    Node1# show bgp vpnv6 unicast received-sids  

BGP router identifier 10.1.1.1, local AS number 1
BGP generic scan interval 60 secs
Non-stop routing is enabled
BGP table state: Active
Table ID: 0x0   RD version: 0
BGP main routing table version 50
BGP NSR Initial initsync version 18 (Reached)
BGP NSR/ISSU Sync-Group versions 0/0
BGP scan interval 60 secs

Status codes: s suppressed, d damped, h history, * valid, > best
              i - internal, r RIB-failure, S stale, N Nexthop-discard
Origin codes: i - IGP, e - EGP, ? - incomplete
   Network            Next Hop                            Received Sid
Route Distinguisher: 8:8
*>i3008::8:8:8:8/128  10.1.1.2                            fc00:0:2:42::
* i                   2400:2020:42:2fff::1
                                                          fc00:0:2:42::
Route Distinguisher: 100:6 (default for vrf vrf_cust6)
*> 3001::1:1:1:1/128  11.1.1.2                            NO SRv6 Sid
*> 3001::2:2:2:2/128  11.1.1.2                            NO SRv6 Sid
*> 3001::3:3:3:3/128  11.1.1.2                            NO SRv6 Sid
*> 3001::5:5:5:5/128  11.1.1.2                            NO SRv6 Sid
*> 3001::12:1:1:5/128 13.2.2.2                            NO SRv6 Sid
*>i3008::8:8:8:8/128  10.1.1.2                            fc00:0:2:42::


    Node1# show bgp vrf vrf_cust6 local-sids 
BGP VRF vrf_cust6, state: Active
BGP Route Distinguisher: 10.1.1.1:0
VRF ID: 0x60000004
BGP router identifier 10.1.1.1, local AS number 1
Non-stop routing is enabled
BGP table state: Active
Table ID: 0xe0000013   RD version: 37
BGP main routing table version 37
BGP NSR Initial initsync version 18 (Reached)
BGP NSR/ISSU Sync-Group versions 0/0

Status codes: s suppressed, d damped, h history, * valid, > best
              i - internal, r RIB-failure, S stale, N Nexthop-discard
Origin codes: i - IGP, e - EGP, ? - incomplete
   Network            Local Sid                                   Alloc mode   Locator
Route Distinguisher: 8:8
*>i3008::8:8:8:8/128  NO SRv6 Sid                                 -            -
* i                   NO SRv6 Sid                                 -            -
Route Distinguisher: 100:6 (default for vrf vrf_cust6)
*> 3001::1:1:1:1/128  fc00:0:1:40::                               per-vrf      locator1
*> 3001::2:2:2:2/128  fc00:8:1:40::                               per-vrf      locator2
*> 3001::3:3:3:3/128  fc00:9:1:40::                               per-vrf      locator4
*> 3001::4:4:4:4/128  fc00:9:1:41::                               per-ce       locator4
*> 3001::5:5:5:5/128  NO SRv6 Sid                                 -            -
*> 3001::12:1:1:5/128 NO SRv6 Sid                                 -            -
*>i3008::8:8:8:8/128  NO SRv6 Sid                                 -            -


    Node1# show bgp vrf vrf_cust6 received-sids 
BGP VRF vrf_cust6, state: Active
BGP Route Distinguisher: 100:6
VRF ID: 0x60000004
BGP router identifier 10.1.1.1, local AS number 1
Non-stop routing is enabled
BGP table state: Active
Table ID: 0xe0000013   RD version: 37
BGP main routing table version 37
BGP NSR Initial initsync version 18 (Reached)
BGP NSR/ISSU Sync-Group versions 0/0

Status codes: s suppressed, d damped, h history, * valid, > best
              i - internal, r RIB-failure, S stale, N Nexthop-discard
Origin codes: i - IGP, e - EGP, ? - incomplete
   Network            Next Hop                            Received Sid
Route Distinguisher: 100:6 (default for vrf vrf_cust6)
*> 3001::1:1:1:1/128  11.1.1.2                            NO SRv6 Sid
*> 3001::2:2:2:2/128  11.1.1.2                            NO SRv6 Sid
*> 3001::3:3:3:3/128  11.1.1.2                            NO SRv6 Sid
*> 3001::5:5:5:5/128  11.1.1.2                            NO SRv6 Sid
*> 3001::12:1:1:5/128 13.2.2.2                            NO SRv6 Sid
*>i3008::8:8:8:8/128  10.1.1.2                            fc00:0:2:42::

What to do next

Verify SRv6-based IPv6 L3VPN configuration

Verify SRv6-based IPv6 L3VPN configuration

This example involves a VPNv6 scenario where Node1 (Ingress PE) and Node4/Node5 (Egress PEs) are configured for SRv6-based L3VPN. The provided command sequence demonstrates how to verify SRv6 L3VPN configurations for a specific VRF, using per VRF label allocation mode.

Procedure

  1. Observe the uDT6 SID associated with the IPv6 L3VPN, where uDT6 behavior represents Endpoint with decapsulation and IPv6 table lookup.

    Example:

    Node1# show segment-routing srv6 sid
Fri Jan 29 19:31:53.293 UTC

*** Locator: 'Node1-locator' ***

SID                         Behavior          Context                           Owner               State  RW
--------------------------  ----------------  ------------------------------    ------------------  -----  --
cafe:0:1::                  uN (PSP/USD)      'default':1                       sidmgr              InUse  Y
cafe:0:1:e000::             uA (PSP/USD)      [Hu0/0/0/0, Link-Local]:0         isis-1              InUse  Y
cafe:0:1:e001::             uA (PSP/USD)      [Hu0/0/0/1, Link-Local]:0         isis-1              InUse  Y
cafe:0:1:e002::             uDT4              'vrf_cust1'                       bgp-100             InUse  Y
cafe:0:1:e003::             uDT4              'vrf_cust2'                       bgp-100             InUse  Y
cafe:0:1:e004::             uDT4              'vrf_cust3'                       bgp-100             InUse  Y
cafe:0:1:e005::             uDT4              'vrf_cust4'                       bgp-100             InUse  Y
cafe:0:1:e006::             uDT4              'vrf_cust5'                       bgp-100             InUse  Y
cafe:0:1:e007::             uA (PSP/USD)      [Hu0/0/0/0, Link-Local]:0:P       isis-1              InUse  Y
cafe:0:1:e008::             uA (PSP/USD)      [Hu0/0/0/1, Link-Local]:0:P       isis-1              InUse  Y
cafe:0:1:e009::             uDT6              'default'                         bgp-100             InUse  Y
cafe:0:1:e00a::             uDT6              'vrf_cust6'                       bgp-100             InUse  Y

  2. Verify the SRv6 based L3VPN configuration using the show bgp vpnv6 unicast commands on the Ingress PE.

    Example:

    Node1# show bgp vpnv6 unicast summary
Fri Jan 29 19:33:01.177 UTC
BGP router identifier 1.1.1.1, local AS number 100
BGP generic scan interval 60 secs
Non-stop routing is enabled
BGP table state: Active
Table ID: 0x0   RD version: 0
BGP main routing table version 6
BGP NSR Initial initsync version 4 (Reached)
BGP NSR/ISSU Sync-Group versions 0/0
BGP scan interval 60 secs

BGP is operating in STANDALONE mode.


Process       RcvTblVer   bRIB/RIB   LabelVer  ImportVer  SendTblVer  StandbyVer
Speaker               6          6          6          6           6           0

Neighbor        Spk    AS MsgRcvd MsgSent   TblVer  InQ OutQ  Up/Down  St/PfxRcd
cafe:0:4::4       0   100     122     123        6    0    0 00:20:05          1
cafe:0:5::5       0   100     111     111        0    0    0 00:49:46          1

Node1# show bgp vpnv6 unicast rd 100:6
Fri Jan 29 19:41:01.334 UTC
BGP router identifier 1.1.1.1, local AS number 100
BGP generic scan interval 60 secs
Non-stop routing is enabled
BGP table state: Active
Table ID: 0x0   RD version: 0
BGP main routing table version 8
BGP NSR Initial initsync version 4 (Reached)
BGP NSR/ISSU Sync-Group versions 0/0
BGP scan interval 60 secs

Status codes: s suppressed, d damped, h history, * valid, > best
              i - internal, r RIB-failure, S stale, N Nexthop-discard
Origin codes: i - IGP, e - EGP, ? - incomplete
   Network            Next Hop            Metric LocPrf Weight Path
Route Distinguisher: 100:6 (default for vrf vrf_cust6)
*> 3001::12:1:1:1/128 ::                       0         32768 ?
*>i3001::12:1:1:4/128 cafe:0:4::4              0    100      0 ?
*>i3001::12:1:1:5/128 cafe:0:5::5              0    100      0 ?

Processed 3 prefixes, 3 paths

    Node1# show bgp vpnv6 unicast rd 100:6 3001::12:1:1:4/128
Fri Jan 29 19:41:42.008 UTC
BGP routing table entry for 3001::12:1:1:4/128, Route Distinguisher: 100:6
Versions:
  Process           bRIB/RIB  SendTblVer
  Speaker                  6           6
Last Modified: Jan 29 19:29:35.858 for 00:12:06
Paths: (1 available, best #1)
  Not advertised to any peer
  Path #1: Received by speaker 0
  Not advertised to any peer
  Local, (received & used)
    cafe:0:4::4 (metric 30) from cafe:0:4::4 (1.1.1.4)
      Received Label 0xe00a00
      Origin incomplete, metric 0, localpref 100, valid, internal, best, group-best, import-candidate, imported
      Received Path ID 0, Local Path ID 1, version 6
      Extended community: RT:100:6
      PSID-Type:L3, SubTLV Count:1
       SubTLV:
        T:1(Sid information), Sid:cafe:0:4::, Behavior:62, SS-TLV Count:1
         SubSubTLV:
          T:1(Sid structure):
      Source AFI: VPNv6 Unicast, Source VRF: vrf_cust6, Source Route Distinguisher: 100:6

  3. Verify the BGP prefix information for VRF instances.

    Example:

    Node1# show bgp vrf vrf_cust6 ipv6 unicast
Fri Jan 29 19:42:05.675 UTC
BGP VRF vrf_cust6, state: Active
BGP Route Distinguisher: 100:6
VRF ID: 0x60000007
BGP router identifier 1.1.1.1, local AS number 100
Non-stop routing is enabled
BGP table state: Active
Table ID: 0xe0800016   RD version: 8
BGP main routing table version 8
BGP NSR Initial initsync version 4 (Reached)
BGP NSR/ISSU Sync-Group versions 0/0

Status codes: s suppressed, d damped, h history, * valid, > best
              i - internal, r RIB-failure, S stale, N Nexthop-discard
Origin codes: i - IGP, e - EGP, ? - incomplete
   Network            Next Hop            Metric LocPrf Weight Path
Route Distinguisher: 100:6 (default for vrf vrf_cust6)
*> 3001::12:1:1:1/128 ::                       0         32768 ?
*>i3001::12:1:1:4/128 cafe:0:4::4              0    100      0 ?
*>i3001::12:1:1:5/128 cafe:0:5::5              0    100      0 ?

Processed 3 prefixes, 3 paths

Node1# show bgp vrf vrf_cust6 ipv6 unicast 3001::12:1:1:4/128

BGP routing table entry for 3001::12:1:1:4/128, Route Distinguisher: 100:6
Versions:
  Process           bRIB/RIB  SendTblVer
  Speaker                 17          17
Last Modified: Jan 15 16:50:44.032 for 01:48:21
Paths: (1 available, best #1)
  Not advertised to any peer
  Path #1: Received by speaker 0
  Not advertised to any peer
  Local, (received & used)
    cafe:0:4::4 (metric 30) from cafe:0:4::4 (1.1.1.4)
      Received Label 0xe00a00
      Origin incomplete, metric 0, localpref 100, valid, internal, best, group-best, import-candidate, imported
      Received Path ID 0, Local Path ID 1, version 17
      Extended community: RT:100:6
      PSID-Type:L3, SubTLV Count:1
       SubTLV:
        T:1(Sid information), Sid:cafe:0:4::, Behavior:62, SS-TLV Count:1
         SubSubTLV:
          T:1(Sid structure):
      Source AFI: VPNv6 Unicast, Source VRF: vrf_cust6, Source Route Distinguisher: 100:6

  4. Verify the current routes in the Routing Information Base (RIB).

    Example:

    Node1# show route vrf vrf_cust6 ipv6 unicast
Fri Jan 29 19:43:28.067 UTC

Codes: C - connected, S - static, R - RIP, B - BGP, (>) - Diversion path
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
       i - ISIS, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, su - IS-IS summary null, * - candidate default
       U - per-user static route, o - ODR, L - local, G  - DAGR, l - LISP
       A - access/subscriber, a - Application route
       M - mobile route, r - RPL, t - Traffic Engineering, (!) - FRR Backup path

Gateway of last resort is not set

L    3001::12:1:1:1/128 is directly connected,
      01:01:23, Loopback105
B    3001::12:1:1:4/128
      [200/0] via cafe:0:4::4 (nexthop in vrf default), 00:13:52
B    3001::12:1:1:5/128
      [200/0] via cafe:0:5::5 (nexthop in vrf default), 00:05:53

Node1# show route vrf vrf_cust6 ipv6 unicast 3001::12:1:1:4/128
Fri Jan 29 19:43:55.645 UTC

Routing entry for 3001::12:1:1:4/128
  Known via "bgp 100", distance 200, metric 0, type internal
  Installed Jan 29 19:29:35.696 for 00:14:20
  Routing Descriptor Blocks
    cafe:0:4::4, from cafe:0:4::4
      Nexthop in Vrf: "default", Table: "default", IPv6 Unicast, Table Id: 0xe0800000
      Route metric is 0
  No advertising protos.

Node1# show route vrf vrf_cust6 ipv6 unicast 3001::12:1:1:4/128 detail
Fri Jan 29 19:44:17.914 UTC

Routing entry for 3001::12:1:1:4/128
  Known via "bgp 100", distance 200, metric 0, type internal
  Installed Jan 29 19:29:35.696 for 00:14:42
  Routing Descriptor Blocks
    cafe:0:4::4, from cafe:0:4::4
      Nexthop in Vrf: "default", Table: "default", IPv6 Unicast, Table Id: 0xe0800000
      Route metric is 0
      Label: None
      Tunnel ID: None
      Binding Label: None
      Extended communities count: 0
      Source RD attributes: 0x0000:100:6
      NHID:0x0(Ref:0)
      SRv6 Headend: H.Encaps.Red [f3216], SID-list {cafe:0:4:e00a::}
  Route version is 0x1 (1)
  No local label
  IP Precedence: Not Set
  QoS Group ID: Not Set
  Flow-tag: Not Set
  Fwd-class: Not Set
  Route Priority: RIB_PRIORITY_RECURSIVE (12) SVD Type RIB_SVD_TYPE_REMOTE
  Download Priority 3, Download Version 3
  No advertising protos.

  5. Verify the current IPv6 Cisco Express Forwarding (CEF) table.

    Example:

    Node1# show cef vrf vrf_cust6 ipv6
Fri Jan 29 19:44:56.888 UTC

::/0
  drop       default handler
3001::12:1:1:1/128
  receive    Loopback105
3001::12:1:1:4/128
  recursive    cafe:0:4::/128
3001::12:1:1:5/128
  recursive    cafe:0:5::/128
fe80::/10
  receive
ff02::/16
  receive
ff02::2/128
  receive
ff02::1:ff00:0/104
  receive
ff05::/16
  receive
ff12::/16
  receive

Node1# show cef vrf vrf_cust6 ipv6 3001::12:1:1:4/128
Fri Jan 29 19:45:23.607 UTC
3001::12:1:1:4/128, version 3, SRv6 Headend, internal 0x5000001 0x30 (ptr 0x78f2e0e0) [1], 0x0 (0x0), 0x0 (0x888a3ac8)
 Updated Jan 29 19:29:35.700
 Prefix Len 128, traffic index 0, precedence n/a, priority 3
   via cafe:0:4::/128, 7 dependencies, recursive [flags 0x6000]
    path-idx 0 NHID 0x0 [0x78cd2a14 0x0]
    next hop VRF - 'default', table - 0xe0800000
    next hop cafe:0:4::/128 via cafe:0:4::/48
    SRv6 H.Encaps.Red SID-list {cafe:0:4:e00a::}

Node1# show cef vrf vrf_cust6 ipv6 3001::12:1:1:4/128 detail
Fri Jan 29 19:45:55.847 UTC
3001::12:1:1:4/128, version 3, SRv6 Headend, internal 0x5000001 0x30 (ptr 0x78f2e0e0) [1], 0x0 (0x0), 0x0 (0x888a3ac8)
 Updated Jan 29 19:29:35.700
 Prefix Len 128, traffic index 0, precedence n/a, priority 3
  gateway array (0x78afe238) reference count 1, flags 0x2010, source rib (7), 0 backups
                [1 type 3 flags 0x48441 (0x78ba9a60) ext 0x0 (0x0)]
  LW-LDI[type=0, refc=0, ptr=0x0, sh-ldi=0x0]
  gateway array update type-time 1 Jan 29 19:29:35.699
 LDI Update time Jan 29 19:29:35.701

  Level 1 - Load distribution: 0
  [0] via cafe:0:4::/128, recursive

   via cafe:0:4::/128, 7 dependencies, recursive [flags 0x6000]
    path-idx 0 NHID 0x0 [0x78cd2a14 0x0]
    next hop VRF - 'default', table - 0xe0800000
    next hop cafe:0:4::/128 via cafe:0:4::/48
    SRv6 H.Encaps.Red SID-list {cafe:0:4:e00a::}

    Load distribution: 0 1 (refcount 1)

    Hash  OK  Interface                 Address
    0     Y   HundredGigE0/0/0/0        remote
    1     Y   HundredGigE0/0/0/1        remote