STP Interface Settings

The STP Interface Settings page enables you to configure STP on a per-port basis, and to view the information learned by the protocol, such as the designated bridge.

The defined configuration entered is valid for all flavors of the STP protocol.

To configure STP on an interface, follow these steps:

Procedure

Step 1

Click Spanning Tree > STP Interface Settings.

Step 2

Select an interface and click Edit.

Step 3

Enter the parameters

Interface

Select the Port or LAG on which Spanning Tree is configured.

Edge Port

Enables or disables Fast Link on the port. If Fast Link mode is enabled on a port, the port is automatically set to Forwarding state when the port link is up. Fast Link optimizes the STP protocol convergence. The options are:

  • Enable—Enables Fast Link immediately

  • Disable—Disables Fast Link

BDU Guard

If enabled, the interface will shut down when a BPDU message is received.

BDU Filter

If enabled, the interface will not send and receive BPDU messages.

Path Cost

Set the port contribution to the root path cost or use the default cost generated by the system.

Priority

Set the priority value of the port. The priority value influences the port choice when a bridge has two ports connected in a loop. The priority is a value 0–240, and must bea multiple of 16.

Port State

Displays the current STP state of a port.

  • Disabled—STP is currently disabled on the port. The port forwards traffic while learning MAC addresses.

  • Blocking—The port is currently blocked, and can’t forward traffic (except for BPDU data) or learn MAC addresses.

  • Learning—The port is in Learning mode. The port can’t forward traffic, but it can learn new MAC addresses.

  • Forwarding—The port is in Forwarding mode. The port can forward traffic and learn new MAC addresses.

Designated Bridge ID

Displays the bridge priority and the MAC address of the designated bridge.

Designated Port ID

Displays the priority and interface of the selected port.

Designated Cost

Displays the cost of the port participating in the STP topology. Ports with a lower cost are less likely to be blocked if STP detects loops.
Step 4

Click Apply. The interface settings are written to the Running Configuration file.