Configuring MPLS L3VPN FRR
You can use the following methods to configure MPLS L3VPN FRR:
Method 1—Execute the pic command in BGP-VPN IPv4 unicast address family view. The device calculates a backup next hop for each BGP route in the VPN instance if there are two or more unequal-cost routes to reach the destination.
Method 2—Execute the fast-reroute route-policy command in BGP-VPN IPv4 unicast address family view to use a routing policy. In the routing policy, specify a backup next hop by using the apply fast-reroute backup-nexthop command. The backup next hop calculated by the device must be the same as the specified backup next hop. Otherwise, the device does not generate a backup next hop for the primary route. You can also configure if-match clauses in the routing policy to identify the routes protected by FRR.
If both methods are configured, Method 2 takes precedence over Method 1.
To configure MPLS L3VPN FRR:
Step | Command | Remarks |
|---|---|---|
1. Enter system view. | system-view | N/A |
2. Enable MPLS BFD. | mpls bfd enable | The mpls bfd enable command applies to VPNv4 route backup for a VPNv4 route and IPv4 route backup for a VPNv4 route. For more information about this command, see MPLS Command Reference. |
3. Configure the source IP address for BFD echo packets. | bfd echo-source-ip ip-address | The bfd echo-source-ip command is required when echo-mode BFD is used to detect primary route connectivity in VPNv4 route backup for an IPv4 route. For more information about this command, see High Availability Command Reference. |
4. Use BFD to test the connectivity of an LSP or MPLS TE tunnel. |
| By default, BFD is not configured to test the connectivity of the LSP or MPLS TE tunnel. This step is required for VPNv4 route backup for a VPNv4 route and IPv4 route backup for a VPNv4 route. Use either command depending on the public tunnel type. For more information about the commands in this step, see MPLS Command Reference. |
5. Create a routing policy and enter routing policy view. | route-policy route-policy-name permit node node-number | By default, no routing policies exist. This step is required to enable MPLS L3VPN FRR in Method 2. For more information about this command, see Layer 3—IP Routing Command Reference. |
6. Set the backup next hop for FRR. | apply fast-reroute backup-nexthop ip-address | By default, no backup next hop address is set for FRR. This step is required to enable MPLS L3VPN FRR in Method 2. For more information about this command, see Layer 3—IP Routing Command Reference. |
7. Return to system view. | quit | N/A |
8. Enter BGP instance view. | bgp as-number [ instance instance-name ] | N/A |
9. (Optional.) Use echo-mode BFD to detect the connectivity to the next hop of the primary route. | primary-path-detect bfd echo | By default, ARP is used to detect the connectivity to the next hop. Use this command if necessary in VPNv4 route backup an IPv4 route. For more information about this command, see Layer 3—IP Routing Command Reference. |
10. Enter BGP-VPN instance view. | ip vpn-instance vpn-instance-name | N/A |
11. Enter BGP-VPN IPv4 unicast address family view. | address-family ipv4 [ unicast ] | N/A |
12. Enable MPLS L3VPN FRR. |
| By default, MPLS L3VPN FRR is disabled. Method 1 might result in routing loops. Use it with caution. By default, no routing policy is used. The apply fast-reroute backup-nexthop command can take effect in the routing policy that is being used. Other apply commands do not take effect. For more information about the command, see Layer 3—IP Routing Command Reference. |