Cisco Catalyst 3750 Metro - Spanning-Tree Port-Priority

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Catalyst 3750 Metro Switch Command Reference
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Chapter 2 Catalyst 3750 Metro Switch Cisco IOS Commands
spanning-tree port-priority
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 select 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 ports assigned to it. The setting takes effect when you
assign the port 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 specified port will be put in the forwarding
state if a loop occurs:
Switch(config)# interface fastethernet1/0/2
Switch(config-if)# spanning-tree vlan 20 port-priority 0
This example shows how to set the port-priority value on VLANs 20 to 25:
Switch(config-if)# spanning-tree vlan 20-25 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 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.
priority Number from 0 to 240, in increments of 16. Valid values are 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.
Release Modification
12.1(14)AX This command was introduced.