Configuring a layer 2 interface

Procedure
  1. Change to the interface configuration context for the interface with the command interface.
  2. By default, interfaces are layer 3. To create a layer 2 interface, disable routing with the command no routing.
  3. Set the interface MTU (maximum transmission unit) with the command mtu.
  4. Review interface configuration settings with the command show interface.

Example

switch(config)# interface 1/1/1
switch(config-if)# no routing
switch(config-if)# mtu 1900