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Software Configuration Guide—Release 15.0(2)SG
OL-23818-01
Chapter 18 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.
To configure PVRST+, perform this task:
The following example shows how to configure Rapid-PVST+:
Switch# config t
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# spanning-tree mode rapid-pvst
Switch(config)# int fa 6/4
Switch(config-if)# spanning-tree link-type point-to-point
Switch(config-if)# end
Switch(config)# end
Switch#
23:55:32:%SYS-5-CONFIG_I:Configured from console by console
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 rapid-PVST+.
Step 2 Switch(config)# interface interface/port Switches to interface configuration mode.
Step 3 Switch(config)#
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 rapid-PVST+ configuration.