MST regions

All MSTP switches in a given region must be configured with the same VLANs, and each MSTP switch within the same region must have the same VLAN-to-instance assignments. In addition, a VLAN can belong to only one instance within any region. Within a region:
  • All of the VLANs belonging to a given instance compose a single, active spanning tree topology for that instance.

  • Each instance operates independently of other regions.

Between regions, there is a single, active spanning tree topology.