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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 20 Configuring STP Configuring Spanning-Tree Features
Beginning in privileged EXEC mode, follow these steps to configure the port priority of an interface.
This procedure is optional.
Note The show spanning-tree interface interface-id privileged EXEC command displays information only
if the port is in a link-up operative state. Otherwise, you can use the show running-config interface
privileged EXEC command to confirm the configuration.
To return to the default setting, use the no spanning-tree [vlan vlan-id] port-priority interface
configuration command. For information on how to configure load sharing on trunk ports by using
spanning-tree port priorities, see the “Configuring Trunk Ports for Load Sharing” section on page 15-22.
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 interface interface-id Specify an interface to configure, and enter interface
configuration mode.
Valid interfaces include physical ports and port-channel
logical interfaces (port-channel port-channel-number).
Step 3 spanning-tree port-priority priority Configure the port priority for an interface.
For priority, the range is 0 to 240, in increments of 16; the
default is 128. 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.
Step 4 spanning-tree vlan vlan-id port-priority priority Configure the port priority for a VLAN.
For vlan-id, 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.
For priority, the range is 0 to 240, in increments of 16;
the default is 128. 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.
Step 5 end Return to privileged EXEC mode.
Step 6 show spanning-tree interface interface-id
or
show spanning-tree vlan vlan-id
Verify your entries.
Step 7 copy running-config startup-config (Optional) Save your entries in the configuration file.