15-8
Software Configuration Guide—Release 15.0(2)SG
OL-23818-01
Chapter 15 Configuring Layer 2 Ethernet Interfaces
Configuring Ethernet Interfaces for Layer 2 Switching
This example shows how to verify the trunk configuration:
Switch# show interfaces fastethernet 5/8 trunk
Port Mode Encapsulation Status Native vlan
Fa5/8 desirable n-802.1q trunking 1
Port Vlans allowed on trunk
Fa5/8 1-1005
Port Vlans allowed and active in management domain
Fa5/8 1-6,10,20,50,100,152,200,300,303-305,349-351,400,500,521,524,570,801-8
02,850,917,999,1002-1005
Port Vlans in spanning tree forwarding state and not pruned
Fa5/8 1-6,10,20,50,100,152,200,300,303-305,349-351,400,500,521,524,570,801-8
02,850,917,999,1002-1005
Switch#
Configuring an Interface as a Layer 2 Access Port
Note If you assign an interface to a VLAN that does not exist, the interface is not operational until you create
the VLAN in the VLAN database (see the “Configuring VLANs in Global Configuration Mode” section
on page 13-6).
To configure an interface as a Layer 2 access port, perform this task:
Command Purpose
Step 1 Switch(config)# interface {fastethernet |
gigabitethernet | tengigabitethernet}
slot/port
Specifies the interface to configure.
Step 2 Switch(config-if)# shutdown (Optional) Shuts down the interface to prevent traffic flow un til
configuration is complete.
Step 3 Switch(config-if)# switchport Configures the interface for Layer 2 switching:
You must enter the switchport command once without any
keywords to configure the interface as a Layer 2 port before
you can enter additional switchport commands with
keywords.
Required only if you previously entered the no switchport
command for the interface.
Step 4 Switch(config-if)# switchport mode access Configures the interface as a Layer 2 access port.
Step 5 Switch(config-if)# switchport access vlan
vlan_num Places the interface in a VLAN.
Step 6 Switch(config-if)# no shutdown Activates the interface. (Required only if you had shut down the
interface.)
Step 7 Switch(config-if)# end Exits interface configuration mode.