ip frr (VPN instance view)

Usage Scenario

With the development of the network, services such as audio, online video, and finance have more requirements for real time. Generally, active/standby links are deployed on the network to ensure service stability.

However, under traditional forwarding modes, when multiple routes to the same destination exist, the system selects the optimal route, which is delivered to FIB table to direct data forwarding. When the optimal link is faulty, the system waits for the completion of route convergence, then selects another optimal route, and then deliver the route to the FIB table. Then the service is recovered. This process leads to a long-time service interruption and cannot meet service requirements.

Using the ip frr command, you can enable IP FRR of the private network. IP FRR can specify a backup next hop and a backup interface and set backup forwarding information for IPv4 routes. When the active link is faulty, the system can switch the traffic immediately to the backup link. This process is irrelevant to route convergence and therefore services are interrupted for short time.

Pre-configuration Tasks

You are advised to use the route-policy command to create Route-Policy at first, in which the apply backup-interface command and the apply backup-nexthop command are used to set a backup outbound interface and a backup next hop for IPv4 route of the private network.

The ip frr command should be used with the apply backup-interface command and the apply backup-nexthop command.

• To configure IP FRR for a private network, you need to run the route-policy command to create Route-Policy first. Then set a backup outbound interface and next hop for IPv4 routes of the private network using the apply backup-interface and apply backup-nexthop commands.
• To configure IP+VPN hybrid FRR, you need to run the route-policy command to create Route-Policy first. Then set a backup next hop for IPv4 routes of the private network using the apply backup-nexthop command.

The differences between the IP FRR configuration and IP+VPN hybrid FRR configuration is as follows:

• If the backup next hop and the backup outgoing interface are specified at the same time, the configurations are for IP FRR.

• If only the backup next hop is specified, the configurations are for IP+VPN hybrid FRR. Based on the backup next hop, a matched VPNv4 route from another PE is found. Then a hybrid FRR entry is formed according to the fields of Token, BackupToken, and Label in the route.

• It is invalid to only specify the backup outgoing interface.

Precautions

Only one policy can be used at one time. New configuration will replace the previous one if another policy is configured. Configuration in the system view and that in the VPN instance view will not interfere each other.