Allied Telesis AlliedWare Plus User Manual

C613-50100-01 REV C Command Reference for x930 Series 414
AlliedWare Plus™ Operating System - Version 5.4.6-1.x
INTERFACE COMMANDS
MTU
mtu
Overview Use this command to set the Maximum Transmission Unit (MTU) size for VLANs,
where MTU is the maximum packet size that VLANs can transmit. The MTU size
setting is applied to both IPv4 and IPv6 packet transmission.
Use the no variant of this command to remove a previously specified Maximum
Transmission Unit (MTU) size for VLANs, and restore the default MTU size (1500
bytes) for VLANs.
Syntax
mtu <68-1582>
no mtu
Default The default MTU size is 1500 bytes for VLAN interfaces.
Mode Interface Configuration for VLAN interfaces.
Usage If a device receives an IPv4 packet for Layer 3 switching to another VLAN with an
MTU size smaller than the packet size, and if the packet has the ‘don’t fragment’
bit set, then the device will send an ICMP ‘destination unreachable’ (3) packet
type and a ‘fragmentation needed and DF set’ (4) code back to the source. For
IPv6 packets bigger than the MTU size of the transmitting VLAN interface, an ICMP
‘packet too big’ (ICMP type 2 code 0) message is sent to the source.
MTU size can only be set for VLANs whose member ports are all non-trunked ports.
If a trunked port moves to another VLAN then the trunked port’s MTU size will not
be set to the VLAN’s MTU size, but will instead be set to the default MTU size of
1500 bytes.
Note that show interface output will only show MTU size for VLAN interfaces.
Examples To configure an MTU size of 1500 bytes on interface vlan2, use the commands:
awplus# configure terminal
awplus(config)# interface vlan2
awplus(config-if)# mtu 1500
To configure an MTU size of 1500 bytes on interfaces vlan2 to vlan4, use the
commands:
awplus# configure terminal
awplus(config)# interface vlan2-vlan4
awplus(config-if)# mtu 1500
To restore the MTU size to the default MTU size of 1500 bytes on vlan2, use the
commands
awplus# configure terminal
awplus(config)# interface vlan2
awplus(config-if)# no mtu

Allied Telesis AlliedWare Plus Specifications

General

Brand	Allied Telesis
Model	AlliedWare Plus
Category	Switch
Language	English