If multiple user networks are connected to the same interface of a PE, configure the interfaces of CEs to add specific VLAN IDs to BPDUs before sending them to the PE.
Run the stp bpdu vlan command on an interface of a CE to add a specified VLAN ID to BPDUs before sending them. Then, run the bpdu-tunnel stp vlan command on the interface of the PE that is connected to the CE to allow the BPDUs carrying the specified VLAN ID to be transparently transmitted over the carrier network.
In most cases, the stp bpdu vlan command is configured on the network-side interface of a CE.
Prerequisites
If the interface is a Layer 3 interface, it must have been switched to a Layer 2 interface using the portswitch command.
The interface has been added to a specified VLAN.
Example
# Configure
GE0/1/1 to add VLAN ID 100 to BPDUs before sending them.