Adding PWs to a PW Protection Group

Procedure

1. Run system-view

   The system view is displayed.

2. Run vsi vsi-name

   The view of the created VSI is displayed.

3. Run pwsignal ldp

   The VSI-LDP view is displayed.

4. Run protect-group group-name

   A PW protection group is created, and the PW protection group view is displayed.

5. Run protect-mode pw-redundancy { master | independent }

   The PW redundancy mode is configured for the current PW protection group.

   In HVPLS scenarios, the PW redundancy mode of the PW protection group can only be master. In VPLS accessing VLL scenarios, a bypass PW must be configured between NPEs if the PW redundancy mode of the PW protection group is master.

   

   The PW redundancy mode of the PW protection group must have been configured before you perform the following configurations.

6. Run peer peer-address [ negotiation-vc-id vc-id ] preference preference-value

   A PW is added to the PW protection group, and the priority of the PW is specified. The smaller the value, the higher the priority. Between the two PWs added to a PW protection group, the one with a higher priority functions as the primary PW.

7. (Optional) Run stream-dual-receiving

   Both the primary and secondary PWs are configured to receive packets.

   

   This command helps prevent packet loss during traffic switchbacks, but may incur routing loops.

8. (Optional) Run holdoff holdoffTime

   A switching delay is configured for the PW protection group.

   If a fault occurs on the primary PW, traffic immediately switches to the secondary PW. If the working path flaps or an error occurs in the detection mechanism, traffic frequently switches between the working and protection paths. To prevent this problem, configure a switching delay.

   

   On a VPLS network that uses BFD for fault detection, traffic immediately switches from the primary PW to the secondary PW after BFD detects a fault on the primary PW, irrespective of whether delayed switching is configured. It is recommended that you determine whether to use BFD or delayed switching based on your requirements.

   After you configure a switching delay, traffic forwarded during the delay period will be interrupted if the primary PW fails to recover before the delay period expires.

9. (Optional) Run reroute { delay delay-time | immediately | never }

   A revertive switching policy is configured.

   The reroute command can be used only for a PW protection group with the master/slave PW redundancy mode.

   • delay delay-time: indicates delayed switchback, meaning that traffic is switched back to the primary PW after a delay.
   • immediately: indicates immediate switchback.
   • never: indicates non-switchback, meaning that traffic is not switched back to the primary PW after the primary PW recovers. Traffic is switched back only after the backup PW fails.

   The revertive switching policy for a PW protection group in independent PW redundancy mode can only be immediate switchback and cannot be changed.

   The revertive switching policy affects traffic switchback after the primary PW recovers.

10. Run commit

    The configuration is committed.