stp bpdu-filter default

Usage Scenario

On a network running a spanning tree protocol, if the stp edged-port enable command is used to configure a port as an edge port, the port will not participate in the spanning tree calculation. This speeds up network convergence and improves network stability. This port, however, will still send BPDUs. This may cause BPDUs to be sent to other networks. As a result, these networks flap.

The stp bpdu-filter enable command can be used on the port to address this problem. After the stp bpdu-filter enable command is used on the port, the port will become a BPDU filter port, and will not process BPDUs.

Running the stp bpdu-filter enable command in the interface view configures only the current edge port as a BPDU filter port. If multiple BPDU filter ports are required on a device, the stp bpdu-filter default command can be used in the system view to configure all edge ports as BPDU filter ports. Then run the stp bpdu-filter disable command in the interface view to change the interfaces that do not need to be configured as BPDU filter interfaces into non-BPDU filter interfaces.

Precautions

After the stp bpdu-filter default command is run, a port that has been configured with the undo stp bpdu-filter command will become a BPDU filter port. After the stp bpdu-filter disable command is run, the port that has been configured with the undo stp bpdu-filter command, however, will still serve as a non-BPDU filter port.

After the stp bpdu-filter default and stp edged-port default commands are run in the system view, none of the ports on the device will initiate any BPDUs or initiate a negotiation with the remote device, and all the ports are in the forwarding state. This may lead to a loop and cause a broadcast storm. Exercise caution when using the stp bpdu-filter default and stp edged-port default commands in the system view.