Command Line Interface

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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
spanning-tree mst cost (4-211)

spanning-tree protocol-migration

This command re-checks the appropriate BPDU format to send on the selected
interface.
Syntax
spanning-tree protocol-migration interface
interface
ethernet unit/port
-unit - Stack unit. (Range: 1)
-port - Port number. (Range: 1-26/50)
port-channel channel-id (Range: 1-32)
Command Mode
Privileged Exec
Console(config)#interface ethernet ethernet 1/5
Console(config-if)#spanning-tree mst 1 port-priority 0
Console(config-if)#