Configuring IS-IS SR-MPLS TE and Topology Reporting

Before an SR-MPLS TE tunnel is established, IS-IS SR-MPLS TE and topology reporting must be enabled.

Context

Before an SR-MPLS TE tunnel is established, a forwarder must allocate labels, collect network topology information, and report that information to a controller so that the controller can use the information to compute a path and generate the corresponding label stack. SR-MPLS TE labels can be allocated by the controller or the extended IS-IS protocol on forwarders. Network topology information (including IS-IS-allocated labels) is collected by IS-IS and reported to the controller through BGP-LS.

Procedure

Configure IS-IS SR-MPLS TE.
Perform the following steps on each node of the SR-MPLS TE tunnel to be established:
1. Run system-view
  The system view is displayed.
2. Run isis [ process-id ]
  The IS-IS view is displayed.
3. Run cost-style { compatible [ relax-spf-limit ] | wide | wide-compatible }
  The IS-IS wide metric function is enabled.
4. Run traffic-eng [ level-1 | level-2 | level-1-2 ]
  IS-IS TE is enabled.
  
  If no IS-IS level is specified, the node is a Level-1-2 device that can generate two TEDBs for communicating with Level-1 and Level-2 devices.
5. Run segment-routing mpls
  SR-MPLS is enabled for IS-IS.
  
  After SR is enabled on nodes, an IGP automatically generates an adjacency label. To disable dynamic adjacency label generation, run the segment-routing auto-adj-sid disable command.
6. Run commit
  The configuration is committed.
7. Run quit
  Return to the system view.
Configure topology reporting to the controller.
Perform the following steps on one or more nodes of the SR-MPLS TE tunnel:

A forwarder can report network-wide topology information to the controller after they establish a BGP-LS peer relationship. The following steps can be configured on one or multiple nodes, depending on the network scale.
1. Run isis [ process-id ]
  The IS-IS view is displayed.
2. Run bgp-ls enable [ level-1 | level-2 | level-1-2 ]
  IS-IS is enabled to advertise network topology information to BGP-LS.
  
  To configure IS-IS to advertise the topology information of Level-1 areas and filter out the route prefixes leaked from Level-2 areas to Level-1 areas, run the bgp-ls enable level-1 level-2-leaking-route-ignore command.
3. Run quit
  Return to the system view.
4. Configure the BGP-LS route advertisement capability.
  1. Run bgp { as-number-plain | as-number-dot }
    
    BGP is enabled, and the BGP view is displayed.
  2. Run peer ipv4-address as-number as-number-plain
    
    A BGP peer is created.
  3. Run link-state-family unicast
    
    BGP-LS is enabled, and the BGP-LS view is displayed.
  4. Run peer { group-name | ipv4-address } enable
    
    The device is enabled to exchange BGP-LS routing information with a specified peer or peer group.
5. Run commit
  The configuration is committed.