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Cisco ME 3400 EthernetAccess Switch SoftwareConfiguration Guide
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Chapter11 Configuring VLANs
Displaying VLANs
Displaying VLANs
Use the show vlan privileged EXEC command to display a list of all VLANs on the switch, including
extended-range VLANs. The display includes VLAN status, ports, and configuration inform ation .
Table11-3 lists other privileged EXEC commands for monitoring VLANs.
For more details about the show command options and explanations of output fields, see the command
reference for this release.
Configuring VLAN Trunks
These sections contain this conceptual information:
Trunking Overview, page 11-14
Default Layer 2 Ethernet Interface VLAN Configuration, page 11-16
Configuring an Ethernet Interface as a Trunk Port, page 11-16
Configuring Trunk Ports for Load Sharing, page 11-19

Trunking Overview

A trunk is a point-to-point link between one or more Ethernet switch interfaces and another networking device
such as a router or a switch. Ethernet trunks carry the traffic of multiple VLANs over a single link, and you
can extend the VLANs across an entire network. The switch supports the IEEE 802.1Q industry-standard
trunking encapsulation.
You can configure a trunk on a single Ethernet interface or on an EtherChannel bundl e. For m ore
information about EtherChannels, see Chapter 31, “Configuring EtherChannels.”
Ethernet interfaces support different trunking modes (see Tab le 11- 4). You can set an interface as
trunking or nontrunking.
If you do not intend to trunk across links, use the switchport mode access interface configuration
command to disable trunking.
Table11-3 VLAN Monitoring Commands
Command Purpose
show interfaces [vlan vlan-id] Display characteristics for all interfaces or for the specified
VLAN configured on the switch.
show vlan [id vlan-id] Display parameters for all VLANs or the specified VLAN on the
switch.
show vlan [vlan-name] uni-vlan
type Display UNI isolated or UNI community VLANs by VLAN
name.
show vlan uni-vlan Display UNI community VLANs and associated ports on the
switch.
show vlan uni-vlan type Display UNI isolated and UNI community VLANs on the switch
by VLAN ID.