Which Statuses Does an MSTP Interface Have, and How Does the Interface Process Packets?
Forwarding: In the forwarding state, interfaces forward user traffic. Only the root interface and designated interface can be in the forwarding state.
Learning: This is a transitional status. In the learning state, switches set up media access control (MAC) address tables based on the received user traffic. A switch in the learning state, however, does not forward user traffic.
Discarding: In the discarding state, interfaces block packets, and do not learn MAC addresses.