Configuring Manual VPN IPv6 FRR

Pre-configuration Tasks

Before configuring manual VPN IPv6 FRR, complete the following tasks:

• Configure a routing protocol on the switches for them to communicate.

• Establish a VPN.
• Configure different metrics to generate two routes of different costs.

  

  It is not recommended that the lsp-trigger command be configured on a P node if an LSP is created on the VPN backbone network. Instead, configure the P node to use default settings; otherwise, the VPN FRR switchback may fail.

Context

As networks develop, services, such as voice over IP (VoIP), online video, and finance services, pose increasingly stringent requirements for real-time transmission. Typically, primary and backup links are deployed on a network to ensure stable service transmission.

In the traditional forwarding mode, the switch selects the optimal route out of several routes destined for the same network and delivers the route to the FIB table to guide data forwarding. When the optimal route is faulty, the system waits until route convergence is completed, selects another optimal route, and then delivers the route to the FIB table. The service then can be recovered. This process leads to a long-time service interruption and cannot meet service requirements.

IP services on a VPN are sensitive to packet loss and latency. When the next hop of the primary route from a PE to a CE is unreachable after manual VPN IPv6 FRR is configured on the network, the system rapidly switches traffic to another PE-CE route, ensuring IP service continuity.

Perform the following configurations on the PE.

Only the S5720-EI, S5720-HI, S5720I-SI, S5720S-SI, S5720-SI, S5735-S, S5735S-S, S5735-S-I, S5730-HI, S5730S-EI, S5730-SI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-EI, S6720-HI, S6720S-EI, S6720S-SI, S6720-SI, S6730-H, S6730S-H, S6730-S, and S6730S-S support this function.

Procedure

1. Run system-view

   The system view is displayed.

2. Run route-policyroute-policy-name { permit | deny } node node

   A route policy is created and the route policy view is displayed.

3. (Optional) Run if-match

   The matching conditions are set to filter the routes to be backed up.

   Configure an if-match clause according to (Optional) Configuring an if-match Clause.

   If no matching condition is set, backup outbound interfaces and backup next hops will be set for all VPN IPv6 routes. As a result, backup information will be specified for some routes that do not need to be backed up. To correctly configure the backup relationship between routes, you are advised to configure matching conditions.

4. Run apply ipv6 backup-interfaceinterface-type interface-number

   The backup outbound interface is set.

5. Run apply ipv6 backup-nexthopipv6-address

   The backup next hop is set.

6. Run quit

   Return to the system view.

7. Run ip vpn-instancevpn-instance-name

   The VPN instance view is displayed.

8. Run ipv6-family

   The VPN instance IPv6 address family view is displayed.

9. Run ipv6 frr route-policyroute-policy-name

   Manual VPN IPv6 FRR is enabled.

Verifying the Configuration

Run the display ipv6 routing-table vpn-instancevpn-instance-name verbose command to check the backup next hop and backup outbound interface of a VPN IPv6 route.