To view detour and bypass path information

Purpose

Perform this procedure to view information regarding detour and bypass tunnel paths and their protected LSPs. Detour and bypass paths are typically configured for fast-reroute-enabled LSPs on NEs for service protection against NE or link failure. The RSVP protocol is used to detect an NE or link loss.

Note: This procedure only applies to Dynamic LSPs.

Detours are employed in One-to-One backup configurations. A separate backup LSP is established for each LSP that is backed up.

Bypass Tunnels are employed in Many-to-One backup configurations in which a single backup LSP is used to back up multiple original LSPs.

Whether a path is a detour or bypass path is determined by the Backup Type parameter value specified during LSP creation. The Backup Type parameter can be set only when the Fast Reroute parameter for the LSP is set to true.

Steps
 
1 

Choose Manage→MPLS→Dynamic LSPs. The Manage Dynamic LSPs form opens.

2 

Select the required Dynamic LSP and click Properties. The Dynamic LSP (Edit) form opens.

3 

Click on the RSVP Sessions tab. The detour or bypass originating, transiting, and terminating RSVP sessions associated with the LSP are listed. Type, site, next and previous hop, and other related information is available.

Note: The SRLG Disjoint FRR Properties and SRLG Not Strict FRR Properties indicators apply to primary LSP sessions only, and not to bypass LSP sessions.

4 

Select the desired RSVP session of type detour or bypass and click Properties. The Session (View) form opens.

5 

To view the Protected LSPs for the specific bypass or detour.

Use the following steps:

  1. Click on the Protected LSP Paths tab. All the protected LSPs for a specific bypass or detour tunnel are listed.

  2. Use the scroll bar at the bottom of the list frame to view the available information on the Protected LSPs.

6 

To view the Detour or Bypass Tunnel Paths for the detour or bypass tunnel.

Use the following steps:

  1. Click on the Detour/Bypass Tunnel Path tab. Information regarding the detour or bypass paths is displayed. Sufficient information is provided to permit tracing a path from its originating site, through its transit hops, and to its termination site.

  2. Use the scroll bar at the bottom of the list frame to view the available information on the paths.

7 

To view additional specific Detour or Bypass information, perform the following steps, as appropriate:

  1. For a selected detour session, click on the Detour tab. The Detour Session ID, Detour PLR ID, and Avoided Downstream Site ID are listed.

  2. For a selected bypass session, click on the Bypass Tunnel tab. The Bypass Tunnel’s current State is displayed.

    Note: For the NFM-P to accurately gather the information about the detour and bypass tunnel path (and the LSPs protected by a detour or a bypass tunnel), the NFM-P must be managing all routers participating in the LSP fast reroute. This is required by NFM-P for all SR and 7705 SAR network elements along the primary path of a fast reroute-enabled LSP.

8 

Close the forms.

End of steps