Configure Switch as Root Switch

C

To manually configure a switch to be the root switch, you need to lower the priority number of the switch so that it becomes the least-cost path to the root bridge. The priority number is a value that is assigned to each switch to determine which switch becomes the root bridge in the spanning tree topology.

The default priority value for a switch is 32768, and this value is used to calculate the root bridge. The switch with the lowest priority value becomes the root bridge. If you want to manually configure a switch to be the root bridge, you need to lower its priority value so that it becomes the switch with the lowest priority value.

To configure a switch to be the root bridge, follow these steps:

1. Log in to the switch and enter privileged EXEC mode by typing enable.
2. Enter global configuration mode by typing configure terminal.
3. Lower the priority value of the switch by typing spanning-tree vlan <vlan-id> root primary.
4. Exit configuration mode by typing end.

Note: The vlan-id is the VLAN ID of the VLAN you want to configure the switch for. If you want to configure the switch for all VLANs, you can omit the vlan-id parameter.

The root primary command sets the priority value of the switch to 24576, which is lower than the default value of 32768. This makes the switch the root bridge for the VLAN or VLANs that you have specified. You can use the show spanning-tree command to verify that the switch is the root bridge.

In summary, to manually configure a switch to be the root bridge, you need to lower its priority value using the spanning-tree vlan <vlan-id> root primary command.