(Optional) Configuring BFD for PW
After configuring PWs, configure BFD for PW to detect the faults of the primary PW to speed up fault detection and improve PW switching performance.
Context
If only signaling is used to detect PW faults, PWs are slow to become aware of faults. BFD for PW is often used to quickly detect PW faults.
Generally, BFD for PW only needs to be configured for the primary PW. When BFD for PW detects a fault on the primary PW, BFD for PW immediately triggers an active/standby PW switching.
Procedure
- Run system-view
The system view is displayed.
- Run bfd
BFD is enabled globally, and the BFD view is displayed.
- Run quit
Return to the system view.
- On the UPE or NPE configured with a VSI, run bfd cfg-name bind pw vsi vsi-name peer peer-address [ vc-id vc-id ] [ remote-peer remote-peer-address pw-ttl { auto-calculate | ttl-number } ]
BFD for PW is configured to detect VSI PW faults.
When configuring BFD for PW, be sure to configure the ignore-standby-state command on the SPE. If you do not configure the ignore-standby-state command, the secondary PW remains blocked and the BFD session cannot go Up. Similarly, if you do not configure the ignore-standby-state command, the primary PW stays in the backup state during a delayed traffic switchback and the BFD session cannot go Up.
- Run the following commands to configure BFD session discriminators:
Run discriminator local discr-value
A local discriminator is configured.
Run discriminator remote discr-value
A remote discriminator is configured.
The local discriminator on one end of the BFD session must be the same as the remote discriminator on the other end of the BFD session.
- Run commit
The configuration is committed.
If the status of a PW is Down, the BFD session can be established but cannot go Up.
You must configure or cancel BFD for PW on both ends of a PW. Otherwise, the PW status on both ends may be inconsistent.