loop-detect only-alarm

Function

The loop-detect only-alarm command configures an interface with loop detection enabled to report an alarm only if it detects a loop, without blocking itself.

The undo loop-detect only-alarm command restores the default configuration.

By default, an interface with loop detection enabled reports an alarm if it detects a loop and blocks itself.

Format

loop-detect only-alarm

undo loop-detect only-alarm

Parameters

None

Views

Eth-Trunk sub-interface view, Eth-Trunk interface view, GE sub-interface view, GE interface view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
vlan	write

Usage Guidelines

Usage Scenario

After a device interface detects a loop using the loop detection mechanism, you can run the loop-detect only-alarm command to configure the device interface to report an alarm only if a loop is detected, without blocking itself. This command helps users to flexibly select a processing mode after loop detection.

Prerequisites

L2VPN loop detection has been enabled globally using the loop-detection enable command, and loop detection has been enabled on an interface.

Configuration Impact

After the loop-detect only-alarm command is run on an interface, if the interface detects a loop, it reports an alarm only and does not block the loop interface. The command configuration has the following impacts:

If a loop is detected on an interface after the loop-detect only-alarm command is run on the interface, the interface reports an alarm only and does not block itself.
If the loop-detect only-alarm command is run on an interface on which a loop has been detected, blocking on the interface is disabled. In this case, if the undo loop-detect only-alarm command is run to restore the default configuration on the interface, block the interface again to prevent the loop.

Example

# Configure the interface with loop detection enabled to report an alarm only if a loop is detected, without blocking itself.

<HUAWEI> system-view
[~HUAWEI] loop-detection enable
[*HUAWEI] commit
[~HUAWEI] interface GigabitEthernet0/1/0.1
[*HUAWEI-GigabitEthernet0/1/0.1] loop-detect enable
[*HUAWEI-GigabitEthernet0/1/0.1] loop-detect only-alarm