mtu (VSI view)

Function

The mtu command sets the MTU of a VSI.

The undo mtu command restores the default configuration.

By default, the MTU of a VSI is 1500 bytes.

Format

mtu mtu

undo mtu

Parameters

Parameter	Description	Value
mtu	Specifies the MTU of a VSI.	The value is an integer ranging from 328 to 65535, in bytes. The default MTU (1500 bytes) is recommended in most cases.

Parameter

Description

Value

mtu

Specifies the MTU of a VSI.

The value is an integer ranging from 328 to 65535, in bytes. The default MTU (1500 bytes) is recommended in most cases.

Views

VSI-AUTO view, VSI-BD 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

The MTU set in the VSI view is just used for the negotiation between the two ends of a PW. You only need to ensure that the MTUs of the VSIs in the same VPLS are consistent. The MTU of a VSI is irrespective of the MTU of the outbound interface.

If the MTU of the VSI on the local end is different from that of the same VSI on the remote end, you must change them to be consistent.

During network expansion, if a PE is added to the current network and the MTU of the VSI on the PE is different from that of the VSI on the remote end, the PW cannot be set up between the two ends. Then, you must change them to be consistent. In this situation, you are advised to modify the MTU of the newly added PE.

Configuration Impact

he MTU set in the VSI view is just used for the negotiation between the two ends of a PW and does not affect the size of packets.

For the PW that has been set up after successful negotiation, if you modify the MTU of the VSI on either PW end, a PW negotiation is triggered. Exercise caution when modifying the MTU.

Precautions

If the MTUs of the same VSI on two PEs are different, the two PEs cannot establish a connection.

Different from the MTU set in the interface view, the MTU set in the VSI view takes effect immediately and you do not need to run the reset command.

Example

# Set the MTU of the VSI named company1.

<HUAWEI> system-view
[~HUAWEI] mpls
[*HUAWEI-mpls] quit
[*HUAWEI] mpls l2vpn
[*HUAWEI-l2vpn] quit
[*HUAWEI] vsi company1
[*HUAWEI-vsi-company1] mtu 1600