Specifications

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Cisco MWR 2941 Mobile Wireless Edge Router Release 3.5 Software Configuration Guide, Cisco IOS Release 15.1(3)MR
OL-26895-01
Chapter 10 Configuring MSTP
Configuring MSTP Features
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 Device Priority
You can configure the device priority and make it more likely that a switch will be chosen as the root
switch.
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.
Beginning in privileged EXEC mode, follow these steps to configure the switch priority. This procedure
is optional.
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
interface interface-id Specify an interface to configure, and enter interface
configuration mode. Valid interfaces include physical NNIs or
ENIs with spanning tree enabled, VLANs, and NNIs. The VLAN
ID range is 1 to 4094. The port-channel range is 1 to 48.
Note If the interface is a VLAN, only ports with spanning tree
enabled in the VLAN will run spanning tree.
Step 3
spanning-tree mst instance-id cost cost Configure the cost.
If a loop occurs, the MSTP 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.
Step 4
end Return to privileged EXEC mode.
Step 5
show spanning-tree mst interface interface-id
or
show spanning-tree mst instance-id
Verify your entries.
Step 6
copy running-config startup-config (Optional) Save your entries in the configuration file.