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Catalyst 2960 Switch SoftwareConfiguration Guide
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Chapter15 Configuring STP
Configuring Spanning-Tree Features
Beginning in privileged EXEC mode, follow these steps to configure the cost of an interface. This
procedure is optional.
Note The show spanning-tree interface interface-id privileged EXEC command displays information only
for ports that are in a link-up operative state. Otherwise, you can use the show running-config privileged
EXEC command to confirm the configuration.
To return to the default setting, use the no spanning-tree [vlan vlan-id] cost interface configuration
command. For information on how to configure load sharing on trunk ports by using spanni ng-tree path
costs, see the “Configuring Trunk Ports for Load Sharing” section on page 12-20.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Specify an interface to configure, and enter interface
configuration mode. Valid interfaces include physical ports and
port-channel logical interfaces (port-channel
port-channel-number).
Step3 spanning-tree cost cost Configure the cost for an interface.
If a loop occurs, spanning tree uses the path cost when selecting
an interface to place into the forwarding state. A lower path cost
represents higher-speed transmission.
For cost, the range is 1 to 200000000; the default value is derived
from the media speed of the interface.
Step4 spanning-tree vlan vlan-id cost cost Configure the cost for a VLAN.
If a loop occurs, spanning tree uses the path cost when selecting
an interface to place into the forwarding state. A lower path cost
represents higher-speed transmission.
For vlan-id, 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.
For cost, the range is 1 to 200000000; the default value is
derived from the media speed of the interface.
Step5 end Return to privileged EXEC mode.
Step6 show spanning-tree interface interface-id
or
show spanning-tree vlan vlan-id
Verify your entries.
Step7 copy running-config startup-config (Optional) Save your entries in the configuration file.