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Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 23 Configuring STP and MST
Configuring STP
Disabling Spanning Tree Protocol
To disable spanning tree on a per-VLAN basis, perform this task:
This example shows how to disable spanning tree on VLAN 200:
Switch# configure terminal
Switch(config)# no spanning-tree vlan 200
Switch(config)# end
Switch#
This example shows how to verify the configuration:
Switch# show spanning-tree vlan 200
Spanning tree instance for VLAN 200 does not exist.
Switch#
Enabling Per-VLAN Rapid Spanning Tree
Per-VLAN Rapid Spanning Tree (PVRST+) uses the existing PVST+ framework for configuration
purposes and for interaction with other features. It also supports some of the PVST+ extensions.
Note Beginning in Cisco IOS XE Release 3.8.0E and Cisco IOS Release 15.2(4)E, Per-VLAN Rapid Spanning
Tree (PVRST+) is the default STP mode on Cisco Catalyst 4500 series, Cisco Catalyst 4900M, Cisco
Catalyst 4948E and Cisco Catalyst 4948F switches.
To enable PVRST+, perform this task:
:
The following example shows how to configure PVRST+:
Switch# config t
Enter configuration commands, one per line. End with CNTL/Z.
Command Purpose
Step 1
Switch(config)# no spanning-tree vlan vlan_ID
Disables spanning tree on a per-VLAN basis.
Step 2
Switch(config)# end
Exits configuration mode.
Step 3
Switch# show spanning-tree vlan vlan_ID
Verifies that spanning tree is disabled.
Command Purpose
Step 1
Switch(config)# [no] spantree mode rapid-pvst
Enables PVRST+.
Step 2
Switch(config)# interface interface/port
Switches to interface configuration mode.
Step 3
Switch(config-if)#
spanning-tree link-type point-to-point
Sets the link-type to point-to-point mode for the port.
Step 4
Switch(config-if)# exit
Exits interface mode.
Step 5
Switch(config)# exit
Exits configuration mode.
Step 6
Switch(config-if)# clear spantree
detected-protocols mod/port
Detects any legacy bridges on the port
Step 7
Switch# show spanning-tree summary totals
Verifies the PVRST+ configuration.