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Cisco ME 3400 Ethernet Access Switch Software Configuration Guide
OL-9639-06
Chapter 15 Configuring MSTP
Configuring MSTP Features
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 NNIs or ENIs with spanning
tree enabled, VLANs, and NNI or ENI port channels. The
VLAN ID range is 1 to 4094. The port-channel range is 1 to 48.
Note If a physical interface is a UNI, before attempting to
configure MST port priority, you must enter the
port-type nni interface configuration command or
configure the port as an ENI and enable spanning tree on
the port. See “Enabling Spanning Tree on an ENI”
section on page 14-13.
If the interface is a VLAN, only ports with spanning tree
enabled in the VLAN will run spanning tree.
If the interface is a port channel, all members of the port
channel must be NNIs or ENIs with spanning tree
enabled.
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.