Cisco 7604

19-18
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
OL-4266-08
Chapter 19 Configuring Standard-Compliant IEEE MST
Configuring MST
To return to defaults, do the following:
• To return to the default MST region configuration, use the no spanning-tree mst configuration
global configuration command.
• To return to the default VLAN-to-instance map, use the no instance instance_id [vlan vlan_range]
MST configuration command.
• To return to the default name, use the no name MST configuration command.
• To return to the default revision number, use the no revision MST configuration command.
• To reenable PVST+, use the no spanning-tree mode or the spanning-tree mode pvst global
configuration command.
This example shows how to enter MST configuration mode, map VLANs 10 to 20 to MST instance 1,
name the region region1, set the configuration revision to 1, display the pending configuration, apply the
changes, and return to global configuration mode:
Router(config)# spanning-tree mst configuration
Router(config-mst)# instance 1 vlan 10-20
Router(config-mst)# name region1
Router(config-mst)# revision 1
Router(config-mst)# show pending
Pending MST configuration
Name [region1]
Revision 1
Instances configured 2
Instance Vlans Mapped
-------- ---------------------
0 1-9,21-4094
1 10-20
-------------------------------
Router(config-mst)# exit
Router(config)#
Step 8
Router(config)# spanning-tree mode mst
Enables MST and RSTP.
Caution Changing the spanning tree mode can disrupt
traffic because all spanning tree instances are
stopped for the previous mode and restarted in
the new mode.
You cannot run both MST and PVST+ or both MST and
rapid PVST+ at the same time.
Step 9
Router(config)# end
Returns to privileged EXEC mode.
Step 10
Router# show running-config
Verifies your entries.
Step 11
Router# copy running-config startup-config
(Optional) Saves your entries in the configuration file.
Command Purpose