process-pst

Function

The process-pst command enables a BFD session to modify the port state table or link state table upon detection of a fault.

The undo process-pst command disables a BFD session from modifying the port state table or link state table upon detection of a fault.

By default, a BFD session does not modify the port state table or link state table upon detection of a fault.

Format

process-pst

undo process-pst

Parameters

None

Views

BFD session view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
bfd	write

Usage Guidelines

Usage Scenario

In BFD-based link protection scenarios, you are advised to run the process-pst command to enable a BFD session to modify the port state table or link state table upon detection of a fault so that a fast link switchover can be performed.

Configuration Impact

After the process-pst command is run, the BFD session is associated with the port state table or link state table of the interface to which the BFD session is bound. After the BFD session detects a link down event, the system sets the port state table or link state table of the interface bound to the BFD session to down. Then, the system switches traffic to a working link accordingly.

Precautions

The process-pst command can be run in the view of a single-hop BFD session bound to an interface. If multiple BFD sessions are bound to the same physical interface, only one BFD session can modify the port state table or link state table after the process-pst command is run:

If an interface has only dynamic or static BFD sessions configured, the process-pst command run first takes effect.
If dynamic and static BFD sessions coexist on an interface, the process-pst command configured for the static BFD session takes effect.
If multiple BFD sessions are bound to the same logical interface (sub-interface or VBDIF interface), the process-pst command takes effect for one BFDv4 session and one BFDv6 session.
The process-pst command also takes effect for BFD sessions for LDP LSP, TE LSP, and TE tunnel.

Example

# Enable a BFD session to modify the PST.

<HUAWEI> system-view
[~HUAWEI] bfd
[*HUAWEI-bfd] quit
[*HUAWEI] bfd session bind peer-ip 10.10.20.2 interface GigabitEthernet 0/1/0
[*HUAWEI-bfd-session-session] process-pst