Setting the MTU for a Layer 3 aggregate interface

The MTU of an interface affects IP packets fragmentation and reassembly on the interface.
Prerequisites

You must be in the global configuration context: switch(config)#

Procedure
  1. Enter Layer 3 aggregate interface view by entering: 
    switch(config)# interface lag <ID>
  2. Set the MTU for the Layer 3 aggregate interface: 
    switch(config-lag-if)# ip mtu <size>

    See the Command-Line Interface Guide for your switch and software version for more information about the ip mtu <size> command.