What is MRSTP?

Zyxel_Melen

Background

RSTP has a limitation that the network topology can’t be multi-ring or the count of switch in the ring topology can’t over 16 switches. Otherwise, the spanning protocolcan’t converge and cause network issue.

For multiple ring topology, Zyxel provides MRSTP as a solution. It is a function that havethe benefit of RSTP with multiple STPs. The ports between different STPs will notflood BPDUs to each other.

Topology

The aggregator in this topology is XS3800-28.

Configuration

Aggregate switch

1. Please navigate to Menu >SWITCHING > Spanning Tree Protocol > Spanning Tree Setup. Choose MultipleRapid Spanning Tree(MRSTP) for spanning tree mode and click apply.
2. Please navigate to Menu >SWITCHING > Spanning Tree Protocol >MRSTP. Enable the tree on the topsection, and then enable to specific ports and fix to which tree.

Access switch

1. Enable RSTP on specific ports. (Zyxel switch default spanning tree mode is RSTP.)

Note

1. Every STP has its own attribute and bridge information independently on the MRSTP enabled switch.
2. On the MRSTP enabled switch, each port can belong to one STP only.