isis bfd block

Function

The isis bfd block command prevents an IS-IS interface from dynamically establishing a BFD session.

The undo isis bfd block command restores the default setting.

By default, an interface can dynamically establish a BFD session.

Only the S5720-EI, S5720-HI, S5730-HI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-EI, S6720-HI, S6720S-EI, S6730-H, S6730S-H, S6730-S, and S6730S-S support this command.

Format

isis bfd block

undo isis bfd block

Parameters

None

Views

Interface view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

BFD can provide millisecond-level fault detection, help IS-IS rapidly detect the faults that occur on neighboring devices or links, and instruct IS-IS to recalculate routes for correct packet forwarding. If the network contains unstable links that do not require high reliability and BFD has been enabled, a link cannot transmit data normally when it flaps. You can use the isis bfd block command to prevent specified interfaces from dynamically establishing BFD sessions.

Prerequisites

IS-IS has been enabled on the interface using the isis enable command.

Precautions

If the isis bfd block, isis bfd enable, and isis bfd static commands are executed, only the last command takes effect.

Example

# Prevent VLANIF100 from dynamically establishing a BFD session.

<HUAWEI> system-view
[HUAWEI] isis
[HUAWEI-isis-1] network-entity 01.0000.0000.0001.00
[HUAWEI-isis-1] quit
[HUAWEI] interface vlanif 100
[HUAWEI-Vlanif100] isis enable 1
[HUAWEI-Vlanif100] isis bfd block

# Prevent GE0/0/1 from dynamically establishing a BFD session.

<HUAWEI> system-view
[HUAWEI] isis
[HUAWEI-isis-1] network-entity 01.0000.0000.0001.00
[HUAWEI-isis-1] quit
[HUAWEI] interface gigabitethernet 0/0/1
[HUAWEI-GigabitEthernet0/0/1] undo portswitch
[HUAWEI-GigabitEthernet0/0/1] isis enable 1
[HUAWEI-GigabitEthernet0/0/1] isis bfd block