Span Tree Domains

The switch can be partitioned into multiple virtual bridges. Each virtual bridge can run an independent Spanning Tree instance. Each Spanning Tree instance is called a STPD. Each STPD has its own root bridge and active path. After an STPD is created, one or more VLANs can be assigned to it.

A physical port can belong to multiple STPDs. In addition, a VLAN can span multiple STPDs.

The key points to remember when configuring VLANs and STP are:

  • Each VLAN forms an independent broadcast domain.

  • STP blocks paths to create a loop-free environment.

  • Within any given STPD, all VLANs belonging to it use the same spanning tree.

For detailed information about configuring STP and various STP parameters on the switch, see Configuring STP on the Switch.