unknown-frame

Function

The unknown-frame command specifies the processing mode for received unknown frames.

The unknown-frame command restores the default configuration.

By default, the system broadcasts unknown unicast and multicast frames.

Format

unknown-frame { unicast { broadcast | drop [ mac-learning ] } | multicast { broadcast | drop } }

undo unknown-frame { unicast | multicast } { drop }

Parameters

Parameter	Description	Value
unicast	Specifies the processing mode for received unknown unicast frames.	-
broadcast	Broadcasts the received unknown frames.	-
drop	Drops the received unknown frames.	-
mac-learning	Drops the received unknown unicast frames and learns their MAC addresses.	-
multicast	Specifies the processing mode for received unknown multicast frames.	-

Views

VSI-AUTO view, VSI-BVSI view, VSI-DEFAULT view, VSI-IVSI-BEVPNINTERWORK 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

If a VSI cannot find the entry that matches the destination address of the received frame in the MAC address table, the frame is considered an unknown frame.

After the unknown-frame command is run, unknown frames are divided into unknown unicast frames and unknown multicast frames for processing. The processing modes include drop and broadcast.

Sometimes, you are advised to set the processing mode to drop to avoid attacks or to save system resources and network bandwidth.

Precautions

The unknown-frame unicast drop command discards the received unknown unicast frames and disables MAC address learning.

Example

# Configure the VSI to drop the received unknown unicast frames.

<HUAWEI> system-view
[~HUAWEI] mpls
[*HUAWEI-mpls] quit
[*HUAWEI] mpls l2vpn
[*HUAWEI-l2vpn] quit
[*HUAWEI] vsi company1
[*HUAWEI-vsi-company1] unknown-frame unicast drop