ipv6 mtu

Function

The ipv6 mtu command sets the MTU on the interface for sending IPv6 packets.

The undo ipv6 mtu command restores the default MTU of IPv6 packets on an interface.

By default, the MTU of IPv6 packets on an interface is 1500 bytes.

For the S5732-H, S6720-HI, S6730-S, S6730S-S, S6730S-H, and S6730-H, this command does not take effect on the IPv6 packets matching ND entries. That is, the MTU of IPv6 packets matching ND entries on the devices is always 1500 bytes.

Format

ipv6 mtu mtu

undo ipv6 mtu

Parameters

Parameter	Description	Value
mtu	Specifies the MTU value.	For GE interfaces, GE sub-interfaces, XGE interfaces, XGE sub-interfaces, MultiGE interfaces, MultiGE sub-interfaces, 25GE interfaces, 25GE sub-interfaces, tunnel interfaces, and VLANIF interfaces, the value is an integer that ranges from 1280 to 9600, in bytes. For other interfaces, the value is an integer that ranges from 1280 to 1500, in bytes. The default value is 1500.

Parameter

Description

Value

mtu

Specifies the MTU value.

For GE interfaces, GE sub-interfaces, XGE interfaces, XGE sub-interfaces, MultiGE interfaces, MultiGE sub-interfaces, 25GE interfaces, 25GE sub-interfaces, tunnel interfaces, and VLANIF interfaces, the value is an integer that ranges from 1280 to 9600, in bytes.
For other interfaces, the value is an integer that ranges from 1280 to 1500, in bytes.

The default value is 1500.

Views

Interface view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

If the traffic processing capability of a link connecting the source and destination ends changes, you can use this command to set the MTU of IPv6 packets on an interface. If the packet length is larger than the IPv6 MTU of the interface, the system fragments the packet based on the configured MTU value before forwarding the packet.

Prerequisites

The IPv6 function has been enabled on the interface using the ipv6 enable command in the interface view.

Precautions

The directly-connected interfaces must be configured with the same IPv6 MTU values.

Example

# Set the MTU of IPv6 packets on VLANIF2 to 1280 bytes.

<HUAWEI> system-view 
[HUAWEI] ipv6
[HUAWEI] interface vlanif 2 
[HUAWEI-Vlanif2] ipv6 enable 
[HUAWEI-Vlanif2] ipv6 mtu 1280

# Set the MTU of IPv6 packets on GE0/0/1 to 1280 bytes.

<HUAWEI> system-view
[HUAWEI] ipv6
[HUAWEI] interface gigabitethernet 0/0/1
[HUAWEI-GigabitEthernet0/0/1] undo portswitch
[HUAWEI-GigabitEthernet0/0/1] ipv6 enable
[HUAWEI-GigabitEthernet0/0/1] ipv6 mtu 1280