Configuring a VSX switch as root for one or more RPVST instances

To configure the VSX switch as root for one or more RPVST instances, set the bridge identifier to the lowest value.

Every switch running an instance of RPVST has a bridge identifier, which is a unique identifier that helps distinguish the switch from all others. The switch with the lowest bridge identifier is elected as the root for the tree.

Procedure

For a single RPVST instance, enter for example:

switch(config)# spanning-tree vlan 1 priority 1

For multiple RPVST instances, enter a range for example:
```
switch(config)# spanning-tree vlan 1-100 priority 1
```