Multiple Spanning Tree Protocol (MSTP)

Without spanning tree, having more than one active path between a pair of nodes causes loops in the network, which can result in duplication of messages, leading to a “broadcast storm” that can bring down the network. MSTP ensures that only one active path exists between any two nodes in a spanning tree instance. A spanning tree instance comprises a unique set of VLANs, and belongs to a specific spanning tree region. A region can comprise multiple spanning tree instances (each with a different set of VLANs), and allows one active path among regions in a network.

You must have identical MSTP configurations on the primary and secondary VSX switches.


Spanning-tree guards and filters are not allowed for configuration on the ISL.