Spanning-Tree Cost - Cisco Catalyst 2950 Command Reference Manual

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.
Syntax Description
vlan vlan-id
cost
Defaults
The default path cost is computed from the interface bandwidth setting. These are the IEEE default path
cost values:
•
•
•
•
•
•
•
Command Modes Interface configuration
Command History Release
12.0(5.2)WC(1)
12.1(9)EA1
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.
Examples This example shows how to set a path cost of 250 on an interface (an access port):
Switch(config)# interface fastethernet0/4
Switch(config-if)# spanning-tree cost 250
78-11381-05
spanning-tree [vlan vlan-id] cost cost
no spanning-tree [vlan vlan-id] cost
(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.
Path cost can range from 1 to 200000000, with higher values meaning higher costs.
10 Mbps—100
100 Mbps—19
155 Mbps—14
1000 Mbps—4
1 Gbps—4
10 Gbps—2
Speeds greater than 10 Gbps—1
Modification
This command was first introduced.
The range for the cost variable increased.
Catalyst 2950 Desktop Switch Command Reference
spanning-tree cost
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