Specifications

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Catalyst 2950 and Catalyst 2955 Switch Command Reference

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Chapter 2 Cisco IOS Commands

spanning-tree cost

Use the spanning-tree cost interface configuration command 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

Syntax Description

Defaults The default path cost is computed from the interface bandwidth setting. These are the IEEE default path

cost values:

• 10 Mbps—100

• 100 Mbps—19

• 155 Mbps—14

• 1000 Mbps—4

• 1 Gbps—4

• 10 Gbps—2

• Speeds greater than 10 Gbps—1

Command Modes Interface configuration

Command History

Usage Guidelines When you configure the cost, higher values represent higher costs.

You can set a cost on a VLAN that does not exist. The setting takes effect when the VLAN exists.

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.

vlan vlan-id (Optional) VLAN ID associated with a spanning-tree instance. The range is 1 to

4094 when the enhanced software image (EI) is installed and 1 to 1005 when the

standard software image (SI) is installed. Do not enter leading zeros.

cost Path cost can range from 1 to 200000000, with higher values meaning higher costs.

Release Modification

12.0(5.2)WC(1) This command was first introduced.

12.1(9)EA1 The range for the cost variable increased.