Changing The Vlan-Bridge Spanning-Tree Priority; Changing The Interface Priority - Cisco WS-C3560-48PS-S Software Configuration Manual

Configuring Fallback Bridging

Changing the VLAN-Bridge Spanning-Tree Priority

You can globally configure the VLAN-bridge spanning-tree priority of a switch when it ties with another
switch for the position as the root switch. You also can configure the likelihood that the switch will be
selected as the root switch.
Beginning in privileged EXEC mode, follow these steps to change the switch priority. This procedure is
optional.
Command
Step 1
configure terminal
Step 2
bridge bridge-group priority number
Step 3 end
Step 4 show running-config
Step 5
copy running-config startup-config
To return to the default setting, use the no bridge bridge-group priority global configuration command.
To change the priority on a port, use the bridge-group priority interface configuration command
(described in the next section).
This example shows how to set the switch priority to 100 for bridge group 10:
Switch(config)# bridge 10 priority 100

Changing the Interface Priority

You can change the priority for a port. When two switches tie for position as the root switch, you
configure a port priority to break the tie. The switch with the lowest interface value is elected.
Beginning in privileged EXEC mode, follow these steps to change the interface priority. This procedure
is optional.
Command
Step 1 configure terminal
Step 2
interface interface-id
Step 3
bridge-group bridge-group priority
number
Step 4
end
Catalyst 3560 Switch Software Configuration Guide
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Purpose
Enter global configuration mode.
Change the VLAN-bridge spanning-tree priority of the switch.
For bridge-group, specify the bridge group number. The range is 1
•
to 255.
For number, enter a number from 0 to 65535. The default is 32768.
•
The lower the number, the more likely the switch will be chosen as
the root.
Return to privileged EXEC mode.
Verify your entry.
(Optional) Save your entry in the configuration file.
Purpose
Enter global configuration mode.
Specify the interface to set the priority, and enter interface
configuration mode.
Change the priority of a port.
• For bridge-group, specify the bridge group number. The range is 1
to 255.
• For number, enter a number from 0 to 255 in increments of 4. The
lower the number, the more likely that the port on the switch will
be chosen as the root. The default is 128.
Return to privileged EXEC mode.
Chapter 34 Configuring Fallback Bridging
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