Configuring The Root Switch - Cisco Catalyst 2960 series Configuration Manual

Command or Action
Step 2
configure terminal
Example:
Switch# configure terminal
Step 3 no spanning-tree vlan vlan-id
Example:
Switch(config)# no spanning-tree vlan 300
Step 4 end
Example:
Switch(config)# end
Related Topics
Supported Spanning-Tree Instances, on page 221
Default Spanning-Tree Configuration, on page 223

Configuring the Root Switch

To configure a switch as the root for the specified VLAN, use the spanning-tree vlan vlan-id root global
configuration command to modify the switch priority from the default value (32768) to a significantly lower
value. When you enter this command, the software checks the switch priority of the root switches for each
VLAN. Because of the extended system ID support, the switch sets its own priority for the specified VLAN
to 24576 if this value will cause this switch to become the root for the specified VLAN.
Use the diameter keyword to specify the Layer 2 network diameter (that is, the maximum number of switch
hops between any two end stations in the Layer 2 network). When you specify the network diameter, the
switch automatically sets an optimal hello time, forward-delay time, and maximum-age time for a network
of that diameter, which can significantly reduce the convergence time. You can use the hello keyword to
override the automatically calculated hello time.
This procedure is optional.
SUMMARY STEPS
1. enable
2. configure terminal
3. spanning-tree vlan vlan-id root primary [diameter net-diameter
4. end
Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)
How to Configure Spanning-Tree Features
Purpose
Enters the global configuration mode.
For vlan-id, the range is 1 to 4094.
Returns to privileged EXEC mode.
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