Cisco Cisco IOS Software Release 12.4(15)T

Cisco 1800 series routers, including models 1801, 1802, 1803, 1811, 1812, 1841

Cisco 2600 series routers, including models 2610XM, 2611XM, 2620XM, 2621XM, 2650XM, 
2651XM, 2691

Cisco 2800 series routers, including models 2801, 2811, 2821, 2851

Cisco 3600 series routers, including models 3620, 3640, 3640A, 3660

Cisco 3700 series routers, including models 3725, 3745

Cisco 3800 series routers, including models 3825, 3845

The reduced MAC address feature is required to support 4000 VLANs. Cisco IOS Release 12.1(14)E1 and 
later releases support chassis with 64 or 1024 MAC addresses. For chassis with 64 MAC addresses, Spanning 
Tree Protocol (STP) uses the extended system ID (which is the VLAN ID) plus a MAC address to make the 
bridge ID unique for each VLAN. (Without the reduced MAC address support, 4096 VLANs would require 
4096 MAC addresses on the switch.)

If you configure extended VLANs, you must also enable the spanning-tree extended system-ID feature.

The legacy vlan database mode does not support extended VLAN configuration.

See the vlan (config-VLAN submode) command for information on the commands that are available 
under config-VLAN submode.

This example shows how to add a new VLAN and enter config-VLAN submode: 

Router (config)# vlan 2

Router (config-vlan)# 

This example shows how to add a range of new VLANs and enter config-VLAN submode: 

Router (config)# vlan 2,5,10-12,20,25,4000

Router (config-vlan)# 

This example shows how to delete a VLAN:

Router (config)# no vlan 2

Router (config)# 

Configures a specific VLAN.