Displaying Vlans; Configuring Vlan Trunks; Trunking Overview - Cisco Catalyst 2950 Software Configuration Manual

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 information. To
view normal-range VLANs in the 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.
Table 16-3
Table 16-3
Command
show
show current [vlan-id]
show interfaces [vlan
vlan-id]
show running-config vlan Privileged EXEC
show vlan [id vlan-id]
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 describe how VLAN trunks function on the switch:
•
•
•

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. Fast Ethernet and Gigabit 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 IEEE 802.1Q, the industry-standard trunking encapsulation.
Figure 16-2
Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
16-14
lists the commands for monitoring VLANs.
VLAN Monitoring Commands
Command Mode
VLAN configuration
VLAN configuration
Privileged EXEC
Privileged EXEC
Trunking Overview, page 16-14
IEEE 802.1Q Configuration Considerations, page 16-16
Default Layer 2 Ethernet Interface VLAN Configuration, page 16-17
shows a network of switches that are connected by IEEE 802.1Q trunks.
Chapter 16
Purpose
Display status of VLANs in the VLAN database.
Display status of all or the specified VLAN in the
VLAN database.
Display characteristics for all interfaces or for
the specified VLAN configured on the switch.
Display all or a range of VLANs on the switch.
Display parameters for all VLANs or the
specified VLAN on the switch.
Configuring VLANs
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