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Catalyst2950 and Catalyst2955 Switch Software Configuration Guide
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Chapter14 Configuring STP
Configuring Spanning-Tree Features
To return the interface to its default setting, use the no spanning-tree [vlan vlan-id] cost interface
configuration command. For information on how to configure load shari ng on t run k po rts by using
spanning-tree path costs, see the “Load Sharing Using STP” section on page 17-22.
Configuring the Switch Priority of a VLAN
You can configure the switch priority and make it more likely that the switch will be chosen as the root
switch.
Note Exercise care when using this command. For most situations, we recommend that you use the
spanning-tree vlan vlan-id root primary a nd the spanning-tree vlan vlan-id root secondary global
configuration commands to modify the switch priority.
Beginning in privileged EXEC mode, follow these steps to configure the switch priority of a VLA N. This
procedure is optional.
To return the switch to its default setting, use the no spanning-tree vlan vlan-id priority global
configuration command.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 spanning-tree vlan vlan-id priority priority Configure the switch priority of a VLAN.
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 1005 when the SI is installed and 1 to 4094
when the EI is installed.
For priority, the range is 0 to 61440 in increments of
4096; the default is 32768. The lower the number, the
more likely the switch will be chosen as the root switch.
Valid priority values are 4096, 8192, 12288, 16384,
20480, 24576, 28672, 32768, 36864, 40960, 45056,
49152, 53248, 57344, and 61440. All other values are
rejected.
Step3 end Return to privileged EXEC mode.
Step4 show spanning-tree vlan vlan-id Verify your entries.
Step5 copy running-config startup-config (Optional) Save your entries in the configuration file.