Specifications

5-5
Cisco MWR 2941 Mobile Wireless Edge Router Release 3.5 Software Configuration Guide, Cisco IOS Release 15.1(3)MR
OL-26895-01
Chapter 5 Configuring Layer 2 Interfaces
Configuring Layer 2 Optional Interface Features
Configuring a Layer 2 Interface as a Layer 2 Trunk
Follow these steps to configure an interface as a Layer 2 trunk.
Command Purpose
Step 1
enable
Example:
Router> enable
Router#
Enter enable mode.
Step 2
configure terminal
Example:
Router# configure terminal
Router(config)#
Enter configuration mode.
Step 3
interface interface slot/port
Example:
Router(config)# interface
fastethernet 1/0
Enter configuration for the interface that you want to modify.
Step 4
shutdown
Example:
Router(config-if)# shutdown
Shut down the interface.
Step 5
switchport mode trunk
Example:
Router(config-if)# switchport mode
trunk
Use the switchport mode trunk command to configure the interface as a
Layer 2 trunk.
Note The encapsulation is always set to dot1q.
Step 6
switchport trunk native vlan vlan
Example:
Router(config-if)# switchport trunk
native vlan 1
If you are configuring an 802.1Q trunk, specify the native VLAN.
Otherwise, proceed to the Step 7.
Step 7
switchport trunk allowed vlan add
vlan
Example:
Router(config-if)# switchport trunk
allowed vlan add vlan1, vlan2, vlan3
Use the switchport trunk allowed vlan command to configure the list of
VLANs allowed on the trunk. The add, except, none, or remove
keywords specify the action to take for the specified VLANs.
Note All VLANs are allowed by default. You cannot remove any of the
default VLANs from a trunk.