Command Line Interface
4-234
4
• Each spanning-tree instance is associated with a unique set of VLAN IDs.
• This command is used by the multiple spanning-tree algorithm to determine
the best path between devices. Therefore, lower values should be assigned
to interfaces attached to faster media, and higher values assigned to
interfaces with slower media.
• Use the no spanning-tree mst cost command to specify auto-configuration
mode.
• Path cost takes precedence over interface priority.
Example
Related Commands
spanning-tree mst port-priority (4-234)
spanning-tree mst port-priority
This command configures the interface priority on a spanning instance in the
Multiple Spanning Tree. Use the no form to restore the default.
Syntax
spanning-tree mst instance_id port-priority priority
no spanning-tree mst instance_id port-priority
• instance_id - Instance identifier of the spanning tree.
(Range: 0-4094, no leading zeroes)
• priority - Priority for an interface. (Range: 0-240 in steps of 16)
Default Setting
128
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
• This command defines the priority for the use of an interface in the multiple
spanning-tree. If the path cost for all interfaces on a switch are the same, the
interface with the highest priority (that is, lowest value) will be configured as
an active link in the spanning tree.
• Where more than one interface is assigned the highest priority, the interface
with lowest numeric identifier will be enabled.
Example
Related Commands
Console(config)#interface ethernet ethernet 1/5
Console(config-if)#spanning-tree mst 1 cost 50
Console(config-if)#
Console(config)#interface ethernet ethernet 1/5
Console(config-if)#spanning-tree mst 1 port-priority 0
Console(config-if)#