Configuring a User-VLAN Sub-interface on a BRAS's User-Side Interface
When VLAN users access an IP core network through a BRAS, the IP core network cannot identify users' VLAN tags. In this situation, configure a user-VLAN sub-interface on the BRAS to remove the VLAN tags carried in the user VLAN packets.
Context
Usage Scenario
If a Layer 2 network connects to an IP core network through a BRAS, it is recommended that you configure a dot1q or QinQ VLAN tag termination sub-interface on the BRAS to remove the VLAN tags before sending user VLAN packets to the IP core network.
If a Layer 3 network connects to an IP core network through a BRAS, it is recommended that you configure a dot1q or QinQ VLAN tag termination sub-interface on the BRAS to remove the VLAN tags before sending user VLAN packets to the IP core network.
Pre-configuration Tasks
Before configuring a user-VLAN sub-interface on a BRAS's user-side interface, correctly plan the user VLANs to allow the user packets that the sub-interface receives to carry one or two VLAN tags.
Procedure
- Run system-view
The system view is displayed.
- Run interface interface-type interface-number.subinterface-number
The view of a BRAS's user-side Ethernet sub-interface is displayed.
- (Optional) Run qinq-vlan pe-vlan description description
A description is configured for the outer VLAN tag carried in double-tagged packets received by the sub-interface.
When users send double-tagged VLAN packets to go online in batches through a BRAS, with the outer VLAN tag representing services and the inner VLAN tag representing users, to learn only the users' service information, configure a description for the outer VLAN tag carried in double-tagged packets received by the BRAS's user-side sub-interface.
- Run user-vlan { start-vlan-id [ end-vlan-id ] | [ cevlan ] } qinq { start-pe-vlan [ end-pe-vlan ] | [ pevlan ] }
The Ethernet sub-interface is configured as a user-VLAN sub-interfaced, and the user-VLAN view is displayed.
- (Optional) Run vlan vlan-id [ qinq pe-vlan ] description description
A description is configured for the user VLAN.
In VS mode, this command is supported only by the admin VS.
To learn not only online service information but also user information, configure a user VLAN description.
Verifying the Configuration
Run the display sub-interface interface-type interface-number pevlan pevlan [ cevlan cevlan ] command to check information about user-VLAN sub-interfaces.
In VS mode, this command is supported only by the admin VS.