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Spanning-Tree Commands 271
spanning-tree mst cost
The spanning-tree mst cost Interface Configuration mode command configures the path cost for
multiple spanning tree (MST) calculations. If a loop occurs, the spanning tree considers path cost
when selecting an interface to put in the forwarding state. To return to the default configuration,
use the
no form of this command.
Syntax
spanning-tree mst instance-id cost cost
no spanning-tree mst instance-id cost
• instance-ID — ID of the spanning -tree instance (Range: 1-15).
•
cost — The port path cost. (Range: 1 - 200,000,000)
Default Setting
Default path cost is determined by port speed and path cost method (long or short) as shown
below:
Command Modes
Interface Configuration (Ethernet, port-channel) mode
Default Configuration
There is no default configuration for this command.
Example
The following example configures the MSTP instance 1 path cost for Ethernet port e9 to 4.
spanning-tree mst configuration
The spanning-tree mst configuration Global Configuration mode command enables configuring
an MST region by entering the Multiple Spanning Tree (MST) mode.
Interface Long Short
Port-channel 20,000 4
Gigabit Ethernet (1000 Mbps) 20,000 4
Fast Ethernet (100 Mbps) 200,000 19
Ethernet (10 Mbps) 2,000,000 100
Console(config) # interface ethernet 1/e9
Console(config-if) # spanning-tree mst 1 cost 4