dot1q vlan
To assign a VLAN ID to a subinterface (or to modify the VLAN ID that is currently assigned to a subinterface), use the dot1q vlan command in subinterface configuration mode. To remove the VLAN ID assigned to a subinterface, use the no form of this command.
dot1q vlan vlan-id
Syntax Description
vlan-id |
ID of the subinterface. Range is from 1 to 4094 (0 and 4095 are reserved). |
Command Default
No default behavior or values
Command Modes
Subinterface configuration
Command History
Release |
Modification |
---|---|
Release 7.0.12 |
This command was introduced. |
Usage Guidelines
The VLAN ID specifies where 802.1Q tagged packets are sent and received on a specified subinterface. An 802.1Q VLAN subinterface must have a configured VLAN ID to send and receive traffic; without a VLAN ID, the subinterface remains in the down state. All VLAN IDs must be unique among all subinterfaces configured on the same physical interface. To change a VLAN ID, the new VLAN must not already be in use on the same physical interface. To exchange VLAN IDs, you must remove the configuration information and reconfigure the ID for each device.
Note |
The subinterface does not pass traffic without an assigned VLAN ID. |
Note |
The dot1q vlan command is is replaced by the encapsulation dot1q command. It is still available for backward-compatibility, but only for Layer 3 interfaces. The encapsulation dot1q command must be used going forward. |
Task ID
Task ID |
Operations |
---|---|
vlan |
read, write |
Examples
This example shows how to configure the VLAN ID and IP address on a subinterface:
RP/0/RP0/CPU0:router# configure
RP/0/RP0/CPU0:router(config)# interface TenGigE 0/2/0/4.1
RP/0/RP0/CPU0:router(config-subif)# dot1q vlan 10
RP/0/RP0/CPU0:router(config-subif)# ipv4 addr 10.0.0.1/24
This example shows how to configure the VLAN IDs for both VLANS in a single Q-in-Q attachment circuit (AC). In this case, incoming traffic must match both of the VLAN IDs before it is accepted by the subinterface:
RP/0/RP0/CPU0:router# configure
RP/0/RP0/CPU0:router(config)# interface TenGigE 0/2/0/4.1
RP/0/RP0/CPU0:router(config-subif)# dot1q vlan 10 20
This example shows how to configure the VLAN IDs for a Q-in-any AC. In this case, all incoming traffic must have two VLAN tags, where the outer VLAN ID matches the configured value, while the inner VLAN ID can be any value.