Procedure
1. Enter system view. system-view
2. Enter BGP instance view. bgp as-number [ instance instance-name ]
3. Enter BGP-VPN instance view. ip vpn-instance vpn-instance-name
4. Enter BGP-VPN IPv4 unicast address family view or BGP-VPN IPv6 unicast address family view.
Enter BGP-VPN IPv4 unicast address family view. address-family ipv4 [ unicast ]
Enter BGP-VPN IPv6 unicast address family view. address-family ipv6 [ unicast ]
5. Configure the route recursion mode. segment-routing ipv6 { best-effort | traffic-engineer | traffic-engineer best-effort }
By default, a PE searches the IPv6 routing table based on the next hop of a matching route to forward traffic.
Specifying a source address for the outer IPv6 header of SRv6-encapsulated packets
Restrictions and guidelines
To ensure correct traffic forwarding in an IP L3VPN over SRv6 network, you must specify a source address for the outer IPv6 header of SRv6-encapsulated packets.
You cannot specify a loopback address, link-local address, multicast address, or unspecified address as the source IPv6 address. You must specify an IPv6 address of the local device as the source IPv6 address, and make sure the IPv6 address has been advertised by a routing protocol. As a best practice, specify a loopback interface address of the local device as the source IPv6 address.
Procedure
1. Enter system view. system-view
2. Enter SRv6 view. segment-routing ipv6
3. Specify a source address for the outer IPv6 header of SRv6-encapsulated packets.
encapsulation source-address ipv6-address [ ip-ttl ttl-value ]
By default, no source address is specified for the outer IPv6 header of SRv6-encapsulated packets.
Configuring IP L3VPN over SRv6 FRR
About this task
IP L3VPN over SRv6 FRR enables the device to calculate backup routes for all routes of a VPN instance to reduce the traffic interruption caused by link or device failures on the backbone. If the device learns two unequal-cost routes destined for the same network from different peers, the
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optimal route is backed up by the other route. When the optimal route becomes unavailable, the device uses the backup route to forward traffic. At the same time, the device calculates a new optimal route and then uses it to direct traffic forwarding.
Restrictions and guidelines
This feature might cause routing loops in certain conditions. Make sure you are fully aware of this feature when you use it on a live network.
Procedure
1. Enter system view. system-view
2. Configure static BFD.
bfd static session-name [ peer-ipv6 ipv6-address [ vpn-instance vpn-instance-name ] source-ipv6 ipv6-address [ discriminator local
local-value remote remote-value ] [ track-interface interface-type interface-number ] ]
3. Return to system view. quit
4. Enter BGP instance view.
bgp as-number [ instance instance-name ]
5. Configure BGP FRR to use BFD to detect next hop connectivity for the primary route. primary-path-detect bfd echo
By default, BGP FRR uses ARP to detect the connectivity to the next hop of the primary route.
For more information about this command, see BGP commands in Layer 3—IP Routing
Command Reference .
6. Enter BGP-VPN IPv4 unicast address family view, BGP VPNv4 address family view, BGP-VPN
IPv6 unicast address family view, or BGP VPNv6 address family view.
Execute the following commands in sequence to enter BGP-VPN IPv4 unicast address family view:
ip vpn-instance vpn-instance-name
address-family ipv4 [ unicast ]
Enter BGP VPNv4 address family view. address-family vpnv4
Execute the following commands in sequence to enter BGP-VPN IPv6 unicast address family view:
ip vpn-instance vpn-instance-name address-family ipv6 [ unicast ]
Enter BGP VPNv6 address family view. address-family vpnv6
7. Enable FRR for the address family. pic
By default, FRR is disabled for a BGP address family.
For more information about this command, see BGP commands in Layer 3—IP Routing
Command Reference .
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