bfd trigger if-down

Function

The bfd trigger if-down command associates the BFD session status with the bound interface status.

Using the undo bfd trigger if-down command cancels the association between the BFD session status and the bound interface status.

By default, a BFD session is not associated with the bound interface status.

Format

bfd trigger if-down

undo bfd trigger if-down

Parameters

None

Views

100GE-Trunk member Layer 2 interface view, 100GE-Trunk member interface view, Layer 2 100GE interface view, 100GE interface view, Layer 2 10GE interface view, 10GE interface view, 25GE-L2 view, 400GE-L2 view, 400GE interface view, 40GE-Trunk member Layer 2 interface view, 40GE-Trunk member interface view, Layer 2 40GE interface view, 40GE interface view, Layer 2 50GE interface view, 50GE interface view, Eth-Trunk member interface view, FlexE interface view, Layer 2 GE interface view, GE optical interface view, GE interface view, GE electrical interface view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
bfd	write

Usage Guidelines

Usage Scenario

After a fault on a physical interface is detected by BFD and rapidly removed, the BFD session goes Down, whereas the physical interface goes Up. This causes some traffic to fail to be switched and then discarded. To prevent packet loss, run the bfd trigger if-down command to trigger a transient interruption on the interface, which ensures that all traffic is rapidly switched.

Prerequisites

A static single-hop BFD session bound to the interface has been created.
The process-pst command has been configured to allow BFD sessions to modify the PST.

Configuration Impact

If BFD goes Down, the associated interface alternates between Up and Down.

Example

# Associate the BFD session status with the bound interface status.

<HUAWEI> system-view
[~HUAWEI] interface GigabitEthernet0/1/0
[*HUAWEI-GigabitEthernet0/1/0] bfd trigger if-down