(Optional) Configuring FRR

In EVPN VPWS over MPLS multi-homing single-active scenarios, FRR needs to be configured to prevent traffic loss if the primary PE fails.

Usage Scenario

As shown in Figure 1, in the EVPN VPWS over MPLS multi-homing single-active scenario, a CE is dual-homed to PE1 and PE2 in active-active mode, and PE3 forwards traffic to PE1 and PE2 working in active/standby mode. When PE1 is the active device, the red path between CE1 and CE2 is the active path, and the blue path is the standby path. To prevent traffic loss if the active path fails, FRR needs to be configured.

In normal situations, downstream traffic of PE3 is sent to PE1. The local and remote FRR function for MAC routes is enabled on PE1 and PE2. If PE1 detects a fault on the link between itself and CE1, PE1 forwards traffic to PE2 and then to CE1. Remote FRR is enabled on PE3. When PE3 detects a fault between itself and PE1, PE3 rapidly switches traffic to PE2 and then sends traffic to CE1, preventing traffic loss.

Figure 1 EVPN VPWS over MPLS networking

Procedure

Configure the local and remote FRR function for MAC routes on PE1 and PE2.
1. Run system-view
  The system view is displayed.
2. Run evpn vpn-instance vpn-instance-name vpws
  The EVPN VPWS instance view.
3. Run local-remote frr enable
  The local and remote FRR function for MAC routes is enabled for the EVPN VPWS instance.
  
  In addition to enabling the local and remote FRR function for MAC routes in the EVPN VPWS instance view, you can run the local-remote vpws-frr enable command in the global EVPN configuration view to enable the local and remote FRR function for MAC routes.
4. Run commit
  The configuration is committed.
Configure remote FRR on PE3.
1. Run system-view
  The system view is displayed.
2. Run evpn vpn-instance vpn-instance-name vpws
  The EVPN VPWS instance view.
3. Run remote frr enable
  Remote FRR is enabled for the EVPN VPWS instance.
  
  In addition to enabling remote FRR in the EVPN VPWS instance view, you can run the remote vpws-frr enable command in the global EVPN configuration view to enable remote FRR globally. By default, if the remote frr command is not run in the EVPN VPWS instance view, the remote frr command configuration in the global view takes effect. If both the remote frr enable command and the remote frr command are run in the EVPN VPWS instance view, the later configuration takes effect.
4. Run commit
  The configuration is committed.