Spanning-Tree Port-Priority - Cisco Catalyst 2950 Command Reference Manual

Chapter 2 Catalyst 2950 and 2955 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.
Syntax Description
vlan vlan-id
priority
Defaults The default is 128.
Command Modes
Interface configuration
Command History Release
12.0(5.2)WC(1)
12.1(13)EA1
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 only on the range of VLANs specified by that command. On the VLANs
that are not specified by the spanning-tree vlan vlan-id port-priority priority command, the
spanning-tree port-priority priority command takes effect.
Examples
This example shows how to increase the likelihood that the specified port 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.
0L-10102-01
spanning-tree [vlan vlan-id] port-priority priority
no spanning-tree [vlan vlan-id] port-priority
(Optional) VLAN range associated with a spanning-tree instance. You can specify
a single VLAN identified by VLAN ID number, a range of VLANs separated by a
hyphen, or a series of VLANs separated by a comma. The range is 1 to 4094.
The range is 0 to 240 in increments of 16 (0, 16, 32, 48, 64, 80, 96, 112, 128, 144,
160, 176, 192, 208, 224, and 240). All other values are rejected. The lower the
number, the higher the priority.
Modification
This command was introduced.
The value for the priority variable was changed.
Catalyst 2950 and Catalyst 2955 Switch Command Reference
spanning-tree port-priority
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