Users Guide

Table Of Contents
mtu
Sets the link maximum transmission unit (MTU) frame size for an Ethernet L2 or L3 interface.
Syntax
mtu value
Parameters value Enter the maximum frame size in bytes, from 1280 to 65535. Maximum frame size for an
S3000-ON is 12000, and S4000-ON is 9216.
Default 1532 bytes
Command Mode INTERFACE
Usage
Information
To return to the default MTU value, use the no mtu command. If an IP packet includes a L2 header, the
IP MTU must be at least 32 bytes smaller than the L2 MTU.
Port-channels
All members must have the same link MTU value and the same IP MTU value.
The port channel link MTU and IP MTU must be less than or equal to the link MTU and IP MTU
values you configure on the channel members. For example, if the members have a link MTU of
2100 and an IP MTU 2000, the port channels MTU values cannot be higher than 2100 for link MTU
or 2000 bytes for IP MTU.
VLANS
All members of a VLAN must have the same MTU value.
Tagged members must have a link MTU 4 bytes higher than untagged members to account for the
packet tag.
Ensure that the MTU of VLAN members is greater than or equal to the VLAN MTU. OS10 selects
the lowest MTU value configured on the VLAN or VLAN members to be the VLAN MTU.
For example, the VLAN contains tagged members with Link MTU of 1522 and IP MTU of 1500 and
untagged members with Link MTU of 1518 and IP MTU of 1500. The VLANs Link MTU cannot be
higher than 1518 bytes and its IP MTU cannot be higher than 1500 bytes.
Example
OS10(conf-if-eth1/1/7)# mtu 3000
Supported
Releases
10.2.0E or later
negotiation
Configures a negotiation mode on an interface.
Syntax
negotiation {auto | on | off}
Parameters
auto Sets the negotiation mode to the default setting. The default setting depends on the media that
you use.
on Forces interface negotiation.
off Disables interface negotiation.
Defaults Auto
Command Mode INTERFACE CONFIGURATION
Usage
Information
Use the show interfaces command to view the interface negotiation status.
Both sides of the link must have auto-negotiation enabled or disabled for the link to come up.
Use either the negotiation auto command or the no negotiation command to reset the
negotiation mode to its default setting.
Example
OS10(conf-if-eth1/1/50)# negotiation off
OS10(conf-if-eth1/1/50)# show configuration
Interfaces 297