Configuring a bypass tunnel on the PLR
To configure FRR, you must create an MPLS TE tunnel on the PLR, specify the bandwidth that the tunnel can protect, and bind the tunnel to the output interface of the primary CRLSP. This MPLS TE tunnel serves as the bypass tunnel of the primary CRLSP. When the link or node connected to the output interface fails, MPLS TE switches the traffic to the bypass tunnel to ensure uninterrupted traffic forwarding.
The bypass tunnel setup method is the same as a normal MPLS TE tunnel. This section describes only FRR-related configurations.
When configuring a bypass tunnel, follow these guidelines:
You cannot configure FRR for a bypass tunnel. A bypass tunnel cannot act as a primary CRLSP.
The protected interface cannot be the output interface of the bypass tunnel.
You can specify up to three bypass tunnels for a protected interface. If multiple bypass tunnels are specified, the one that can provide node protection is preferred.
To configure a bypass tunnel on the PLR:
Step | Command | Remarks |
|---|---|---|
1. Enter system view. | system-view | N/A |
2. Enter tunnel interface view of the bypass tunnel. | interface tunnel tunnel-number [ mode mpls-te ] | N/A |
3. Specify the destination address of the bypass tunnel. | destination ip-address | The bypass tunnel destination address is the LSR ID of the MP. |
4. Configure the bandwidth that the bypass tunnel can protect. | mpls te backup bandwidth bandwidth | By default, the bypass tunnel does not provide bandwidth protection. You must execute this command to configure the bandwidth that the bypass tunnel can protect. Otherwise, the primary CRLSP cannot be bound to the bypass tunnel successfully. |
5. Return to system view. | quit | N/A |
6. Enter interface view of the output interface of the primary CRLSP. | interface interface-type interface-number | N/A |
7. Specify a bypass tunnel for the protected interface (the current interface). | rsvp fast-reroute bypass-tunnel tunnel tunnel-number | By default, no bypass tunnel is specified for an interface. |