How to configure VLAN on Cisco

Technology: Enterprise Switching
Area: VLAN
Vendor: Cisco
Software: 12.X , 15.X
Platform: Catalyst Switches

A VLAN is a group of end stations in a switched network that is logically segmented by function, team, or application, regardless of the physical locations of the users. VLANs have the same attributes as physical LANs, but you can group end stations even if they are not physically connected to the same switch.

VLANs are numbered from 1 to 4094 (extended range). All configured ports belong to the default VLAN when you first bring up the switch. The default VLAN (VLAN1) uses only default values, and you cannot create, delete, or suspend activity in the default VLAN.

You can create a VLAN by assigning a number to it; you can delete VLANs as well as move them from the active operational state to the suspended operational state. If you attempt to create a VLAN with an existing VLAN ID, the switch goes into the VLAN sub-mode but does not create the same VLAN again.

To create a VLAN:


switch#configure terminal
switch(config)# vlan 15
switch(config-vlan)# name accounting

The name in the above configuration is optional but helps the administrator to keep the config clean

To assign an Ethernet interface to a VLAN 15:

switch#configure terminal
switch(config)# interface FastEthernet 0/1
switch(config-if)# switchport access vlan 15

To verify VLANs you just created, issue:

switch#show vlan