Configuring Forwarding Adjacency

The forwarding adjacency is configured on the ingress of a CR-LSP. The forwarding adjacency allows a route of a CR-LSP to be advertised to neighbors so that these neighbors can use this CR-LSP to transmit traffic.

Context

A routing protocol performs bidirectional detection on a link. The forwarding adjacency needs to be enabled on both ends of a tunnel. The forwarding adjacency allows a node to advertise a CR-LSP route to other nodes. Another tunnel for transferring data packets in the reverse direction must be configured.

Procedure

Run system-view
The system view is displayed.
Run interface tunnel tunnel-number
The view of an MPLS TE tunnel interface is displayed.
Run mpls te igp advertise [ hold-time interval | include-ipv6-isis ] ^*
The forwarding adjacency is configured.

If IPv6 IS-IS is used, the include-ipv6-isis parameter must be configured.
Run mpls te igp metric { absolute | relative } value
The IGP metric value of the MPLS TE tunnel is set.

A proper IGP metric value helps correctly advertise and use a CR-LSP route. The metric value of a CR-LSP must be less than the metric value of an unwanted IGP route.

If relative is configured and IS-IS is used as an IGP, this step cannot modify the IS-IS metric value. To change the IS-IS metric value, configure absolute in this step.
You can select either of the following modes to enable the forwarding adjacency.
- For IS-IS, run isis enable [ process-id ]
  
  IS-IS is enabled on the tunnel interface.
- For OSPF, run the following commands in sequence.
  1. Run the ospf enable [ process-id ] area { area-id | areaidipv4 } command to enable OSPF on the tunnel interface.
  2. Run the quit command to return to the system view.
  3. Run the ospf [ process-id ] command to enter the OSPF view.
  4. Run the enable traffic-adjustment advertise command to enable the forwarding adjacency.
Run commit
The configuration is committed.