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Catalyst 2928 Switch Software Configuration Guide
OL-23389-01
Chapter 17 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 Switch Priority
You can configure the switch priority and make it more likely that the 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.
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.
Command
Purpose