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Catalyst 2940 Switch Software Configuration Guide
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Chapter13 Configuring VLANs Displaying VLANs
Displaying VLANs
Use the show vlan privileged EXEC command to display a list of all VLANs on the switch. The display
includes VLAN status, ports, and configuration information. To view normal-range VLAN s in t he
VLAN database (1 to 1005,) use the show VLAN configuration command (accessed by entering the vlan
database privileged EXEC command). For a list of the VLAN IDs on the switch, use the show
running-config vlan privileged EXEC command, optionally entering a VLAN ID range.
Table13-3 lists the commands for monitoring VLANs.
For more details about the show command options and explanations of output fields, refer to the
command reference for this release.
Configuring VLAN Trunks
These sections describe how VLAN trunks function on the switch:
•Trunking Overview, page 13-11
•802.1Q Configuration Considerations, page 13-13
•Default Layer 2 Ethernet Interface VLAN Configuration, page 13-13

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 s wi t ch . Fast Ethernet and Gigabit Ethernet trunks carry the traffi c of mu l t i pl e VL A N s
over a single link, and you can extend the VLANs across an entire network.
Table13-3 VLAN Monitoring Commands
Command Command Mode Purpose
show VLAN configuration Display status of VLANs in the VLAN database.
show current [vlan-id] VLAN configuration Display status of all or the specified VLAN in the
VLAN database.
show interfaces [vlan
vlan-id]Privileged EXEC Display characteristics for all interfaces or for
the specified VLAN configured on the switch.
show running-config vlan Privileged EXEC Display all or a range of VLANs on the switch.
show vlan [id vlan-id] Privileged EXEC Display parameters for all VLANs or the
specified VLAN on the switch.