Cisco WS-SUP32-GE-3B Software Configuration Guide - Page 268

Configuring MST Chapter 17 Configuring STP and MST Step 3 Step 4 Step 5 Step 6 Command Router(config-if)# spanning-tree mst instance_id cost cost Router(config-if)# end Router# show spanning-tree mst interface interface_id or Router# show spanning-tree mst instance_id Router# copy running-config startup-config Purpose Configures the cost. If a loop occurs, MST uses the path cost when selecting an interface to place into the forwarding state. A lower path cost represents higher-speed transmission. • For instance_id, you can specify a single instance, a range of instances separated by a hyphen, or a series of instances separated by a comma. The range is 0 to 4094. • For cost, the range is 1 to 200000000; the default value is derived from the media speed of the interface. Returns to privileged EXEC mode. Verifies your entries. (Optional) Saves your entries in the configuration file. Note The show spanning-tree mst interface interface_id privileged EXEC command displays information only for ports that are in a link-up operative state. Otherwise, you can use the show running-config privileged EXEC command to confirm the configuration. To return the interface to its default setting, use the no spanning-tree mst instance_id cost interface configuration command. Configuring the Switch Priority You can configure the switch priority so that it is more likely that a switch is chosen as the root bridge. Note Exercise care when using this command. For most situations, we recommend that you use the spanning-tree mst instance_id root primary and the spanning-tree mst instance_id root secondary global configuration commands to modify the switch priority. 17-44 Catalyst Supervisor Engine 32 PISA Cisco IOS Software Configuration Guide, Release 12.2ZY OL-11439-03