mac-withdraw propagate enable

Function

The mac-withdraw propagate enable command enables a PE to forward a received MAC Withdraw message to its peers.

The undo mac-withdraw propagate enable command disables a PE from forwarding a received MAC Withdraw message to its peers.

By default, a PE does not forward a received MAC Withdraw message.

Format

mac-withdraw propagate enable

undo mac-withdraw propagate enable

Parameters

None

Views

VSI-AUTO view, VSI-BD view, VSI-BVSI view, VSI-DEFAULT view, VSI-IVSI-P2P view, VSI-STATIC view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
l2vpn	write

Usage Guidelines

Usage Scenario

On an LDP or BGP AD VPLSnetwork, after a local PE receives a MAC Withdraw message, the local PE needs to forward the MAC Withdraw message to its peers. Otherwise, its peers cannot detect network topology changes or learn new MAC addresses in a timely manner. As a result, traffic loss caused by invalid MAC addresses will occur. To enable a PE to forward a received MAC Withdraw message to its peers, run the mac-withdraw propagate enable command.

Precautions

After you run the mac-withdraw propagate enable command on a PE, the PE forwards a received MAC Withdraw message to its peers according to the split horizon principle:
The MAC Withdraw message received from a UPE will be forwarded to NPEs and other UPEs.
The MAC Withdraw message received from an NPE will be forwarded to UPEs, but will not be forwarded to other NPEs.
The mac-withdraw propagate enable command applies to MAC Withdraw messages carrying either the FEC 128 TLV or the FEC 129 TLV. The upe-upe mac-withdraw enable, upe-npe mac-withdraw enable, and npe-upe mac-withdraw enable commands apply only to MAC Withdraw messages carrying the FEC 128 TLV. The mac-withdraw propagate enable command cannot be used with the upe-upe mac-withdraw enable, upe-npe mac-withdraw enable, or npe-upe mac-withdraw enable command in the same VSI.

Example

# Configure vsi100 on a PE to forward a received MAC Withdraw message to its peers.

<HUAWEI> system-view
[~HUAWEI] mpls
[*HUAWEI-mpls] quit
[*HUAWEI] mpls l2vpn
[*HUAWEI-l2vpn] quit
[*HUAWEI] vsi vsi100
[*HUAWEI-vsi-vsi100] mac-withdraw propagate enable