Specifications

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Catalyst 2950 and Catalyst 2955 Switch Command Reference

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Chapter 2 Cisco IOS Commands

spanning-tree port-priority

Use the spanning-tree port-priority interface configuration command to configure an interface

priority. If a loop occurs, spanning tree can determine which interface to put in the forwarding state. Use

the no form of this command to return to the default setting.

spanning-tree [vlan vlan-id] port-priority priority

no spanning-tree [vlan vlan-id] port-priority

Syntax Description

Defaults The default is 128.

Command Modes Interface configuration

Command History

Usage Guidelines If the variable vlan-id is omitted, the command applies to the spanning-tree instance associated with

VLAN 1.

You can set the priority on a VLAN that has no interfaces assigned to it. The setting takes effect when

you assign the interface to the VLAN.

If you configure an interface with both the spanning-tree vlan vlan-id port-priority priority command

and the spanning-tree port-priority priority command, the spanning-tree vlan vlan-id port-priority

priority command takes effect.

Examples This example shows how to increase the likelihood that the Fast Ethernet interface 0/2 will be put in the

forwarding state if a loop occurs:

Switch(config)# interface fastethernet0/2

Switch(config-if)# spanning-tree vlan 20 port-priority 0

You can verify your settings by entering the show spanning-tree interface interface-id privileged

EXEC command.

vlan vlan-id (Optional) VLAN ID associated with a spanning-tree instance. The range is 1 to

4094 when the enhanced software image (EI) is installed and 1 to 1005 when the

standard software image (SI) is installed. Do not enter leading zeros.

priority Number from 0 to 255. The lower the number, the higher the priority.

Release Modification

12.0(5.2)WC(1) This command was first introduced.