Cisco Catalyst 4500 Series Command Reference Guide

2-1012
Catalyst 4500 Series Switch Cisco IOS Command Reference—Release IOS XE 3.4.0SG and IOS 15.1(2)SG)
OL-27596 -01
Chapter 2 Cisco IOS Commands for the Catalyst 4500 Series Switches
spanning-tree port-priority
spanning-tree port-priority
To prioritize an interface when two bridges compete for position as the root bridge, use the
spanning-tree port-priority command. The priority you set resolves the conflict. To revert to the
default setting, use the no form of this command.
spanning-tree port-priority port_priority
no spanning-tree port-priority
Syntax Description
Defaults Port priority value is set to 128.
Command Modes Interface configuration mode
Command History
Examples This example shows how to increase the possibility that the spanning-tree instance 20 will be chosen as
the root-bridge on interface FastEthernet 2/1:
Switch(config-if)# spanning-tree port-priority 0
Switch(config-if)#
Related Commands
port_priority Port priority; valid values are from 0 to 240 in increments of 16.
Release Modification
12.1(8a)EW Support for this command was introduced on the Catalyst 4500 series switch.
Command Description
spanning-tree cost Calculates the path cost of STP on an interface.
spanning-tree portfast default Enables PortFast by default on all access ports.
spanning-tree portfast (interface
configuration mode)
Enables PortFast mode.
spanning-tree uplinkfast Enables the UplinkFast feature.
spanning-tree vlan Configures STP on a per-VLAN basis.
show spanning-tree Displays spanning-tree state information.

Cisco Catalyst 4500 Series Specifications

General

Series	Catalyst 4500 Series
Category	Switch
Layer Support	Layer 2, Layer 3
Form Factor	Modular chassis
Stackable	No
Chassis Slots	3, 6, 7, 10
Power Supply Options	AC, DC
Redundancy	Power supply, Supervisor engine
Network Management	Cisco IOS Software CLI, SNMP, Cisco Prime Infrastructure
Features	Security, QoS
Port Density	Up to 384 ports per chassis
Security Features	802.1X, ACLs, DHCP Snooping, Dynamic ARP Inspection, IP Source Guard
Supervisor Engine	8-E