19-23
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
OL-4266-08
Chapter 19 Configuring Standard-Compliant IEEE MST
Configuring MST
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 router 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.
Step 3
Router(config-if)#
spanning-tree mst
instance_id
cost
cost
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.
Step 4
Router(config-if)#
end
Returns to privileged EXEC mode.
Step 5
Router#
show spanning-tree
mst
interface
interface_id
or
Router#
show spanning-tree mst
instance_id
Verifies your entries.
Step 6
Router#
copy running-config startup-config
(Optional) Saves your entries in the configuration file.
1.
type
=
ethernet
,
fastethernet
,
gigabitethernet
, or
tengigabitethernet
Command
Purpose