Cisco Systems 312 Switch User Manual


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Cisco Catalyst Switch Module 3110 and 3012 for IBM BladeCenter Software Configuration Guide
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Chapter 18 Configuring MSTP
Configuring MSTP Features
Note If your switch is a member of a switch stack, you must use the spanning-tree mst [instance-id] cost cost
interface configuration command instead of the spanning-tree mst [instance-id] port-priority priority
interface configuration command to select a port to put in the forwarding state. Assign lower cost values
to ports that you want selected first and higher cost values to ports that you want selected last. For more
information, see the “Configuring Path Cost” section on page 18-21.
Beginning in privileged EXEC mode, follow these steps to configure the MSTP port priority of an
interface. This procedure is optional.
Note The show spanning-tree mst interface interface-id privileged EXEC command displays information
only if the port is in a link-up operative state. Otherwise, you can use the show running-config interface
privileged EXEC command to confirm the configuration.
To return the interface to its default setting, use the no spanning-tree mst instance-id port-priority
interface configuration command.
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 ports and port-channel
logical interfaces. The port-channel range is 1 to 48.
Step 3
spanning-tree mst instance-id port-priority priority Configure the port priority.
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 priority, the range is 0 to 240 in increments of 16.
The default is 128. The lower the number, the higher
the priority.
The priority values are 0, 16, 32, 48, 64, 80, 96, 112,
128, 144, 160, 176, 192, 208, 224, and 240. All other
values are rejected.
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.