Adding PWs to a PW Protection Group

Procedure

1. Run system-view

   The system view is displayed.

2. Run vsi vsi-name static

   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

   The PW redundancy mode of the current PW protection group is specified.

   

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

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

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

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

   A revertive switching policy is configured.

   The default revertive switching policy is delayed switchback and the delay is 30s. Only a PW protection group with the master/slave PW redundancy mode allows you to modify the revertive switching policy using the reroute command.

   • 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 affects traffic switchback after the primary PW recovers.

8. (Optional) Run stream-dual-receiving

   The function of the secondary PW to receive and forward traffic from the peer is enabled.

   By default, the secondary PW does not receive traffic from the peer.

   When the network is unstable or a faulty occurs on the device, traffic may switch between the primary and secondary PW. In this case, you need to run the stream-dual-receiving command to enable the secondary PW to receive and forward traffic from the peer. This reduces number of packets lost during switching, but may incur routing loops.

9. (Optional) Run holdoff holdoff-time

   A switching delay is configured for the PW protection group.

   By default, no switching delay is configured for a PW protection group with the PW redundancy mode as master/slave. If a fault occurs on the primary PW, traffic immediately switches from the primary PW 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 avoid such situations, 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, no matter whether delayed switching is configured. It is recommended that you determine whether to use BFD or delayed switching based on your actual network 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.