Spanning-Tree Cost - Cisco Catalyst 3560-X Command Reference Manual

Chapter 2 Catalyst 3750-X and 3560-X Cisco IOS Commands

spanning-tree cost

Syntax Description
Defaults
Command Modes
Command History
Usage Guidelines
Examples
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Use the spanning-tree cost interface configuration command on the switch stack or on a standalone
switch to set the path cost for spanning-tree calculations. If a loop occurs, spanning tree considers the
path cost when selecting an interface to place in the forwarding state. Use the no form of this command
to return to the default setting.
spanning-tree [vlan vlan-id] cost cost
no spanning-tree [vlan vlan-id] cost
vlan vlan-id (Optional) VLAN range associated with a spanning-tree instance. You can specify
a single VLAN identified by VLAN ID number, a range of VLANs separated by a
hyphen, or a series of VLANs separated by a comma. The range is 1 to 4094.
cost Path cost. The range is 1 to 200000000, with higher values meaning higher costs.
The default path cost is computed from the interface bandwidth setting. These are the IEEE default path
cost values:
1000 Mb/s—4
•
• 100 Mb/s—19
10 Mb/s—100
•
Interface configuration
Release
12.2(53)SE2
When you configure the cost, higher values represent higher costs.
If you configure an interface with both the spanning-tree vlan vlan-id cost cost command and the
spanning-tree cost cost command, the spanning-tree vlan vlan-id cost cost command takes effect.
This example shows how to set the path cost to 250 on a port:
Switch(config)# interface gigabitethernet2/0/1
Switch(config-if)# spanning-tree cost 250
This example shows how to set a path cost to 300 for VLANs 10, 12 to 15, and 20:
Switch(config-if)# spanning-tree vlan 10,12-15,20 cost 300
You can verify your settings by entering the show spanning-tree interface interface-id privileged
EXEC command.
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Modification
This command was introduced.
Catalyst 3750-X and 3560-X Switch Command Reference
spanning-tree cost
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