vpls mac-withdraw loop-detect enable

Function

The vpls mac-withdraw loop-detect enable command enables MAC withdraw loop detection.

The undo vpls mac-withdraw loop-detect enable command disables MAC withdraw loop detection.

By default, MAC withdraw loop detection is disabled.

Format

vpls mac-withdraw loop-detect enable

undo vpls mac-withdraw loop-detect enable

Parameters

None

Views

MPLS-L2VPN view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
l2vpn	write

Usage Guidelines

Usage Scenario

On a dual-homing VPLS or HVPLS network, MAC withdraw messages can be forwarded between hub and spoke PWs and between spoke PWs. Incorrect configurations may cause a MAC withdraw message loop, which results in traffic loss. If the loop involves a large number of MAC withdraw messages, denial of service (DoS) attacks may occur. To resolve these problems, run the vpls mac-withdraw loop-detect enable command to enable MAC withdraw loop detection. After you enable MAC withdraw loop detection, a PE immediately discards MAC withdraw messages when it detects a MAC withdraw message loop.

Prerequisites

MPLS L2VPN has been enabled using the mpls l2vpn command.

Example

# Enable MAC withdraw loop detection.

<HUAWEI> system-view
[~HUAWEI] mpls
[*HUAWEI-mpls] quit
[*HUAWEI] mpls l2vpn
[*HUAWEI-l2vpn] vpls mac-withdraw loop-detect enable