554 Spanning Tree Commands
Example
The following example configures the port priority of port 1/g1 to 144.
console(config)#interface ethernet 1/g1
console(config-if-1/g1)#spanning-tree mst 1 port-
priority 144
spanning-tree mst priority
Use the spanning-tree mst priority command in Global Configuration mode 
to set the switch priority for the specified spanning-tree instance. To return to 
the default setting, use the no form of this command.
Syntax
spanning-tree mst 
instance-id
 priority 
priority
no spanning-tree mst 
instance-id 
priority
•
instance-id — 
ID of the spanning-tree instance. (Range: 1-15)
•
priority — 
Sets the switch priority for the specified spanning-tree instance. 
This setting affects the likelihood that the switch is selected as the root 
switch. A lower value increases the probability that the switch is selected as 
the root switch. (Range: 0-61440)
Default Configuration
The default bridge priority for IEEE STP is 32768.
Command Mode 
Global Configuration mode
User Guidelines
The priority value must be a multiple of 4096.
The switch with the lowest priority is selected as the root of the spanning tree.
Example
The following example configures the spanning tree priority of instance 1 to 
4096.