Multiple Layer 2 rings- one VLAN

[Brett Martin]

Hello,

I have a situation where I have an existing Layer 2 RING setup with a spur connection to a server room. There is a root bridge configured in one of the locations of the ring.

We are expanding the network and an additional Layer 2 ring has been designed with a spur connection to the same server room. The architecture is basically 2 separate rings connected to a common server room.

I need some guidance on how to configure for optimal spanning tree (Rapid PVST+) such that one ring topology change does not impact the other.

Any suggestions on how to implement the best design. I am concerned about implementing BPDU filtering but it may be the only option?

What I forgot to mention is that each independent Layer 2 ring connects to the server room with 2 fiber interfaces each. Today RING 1 has one of these 2 connections to the server room blocking.

Thanks,

Brett 

[ematos001]

You have a single broadcast domain (Layer 2) . You should not use BPDU Filter since this will stop the Spanning tree. Just select your Main/Core as the Spanning Tree Root, and leave the rest to spanning tree.

If you have a topology like         a-b-c-d-e    and you set C as the root and each interlink has the same speed then link a to e will be blocked, but it will forward traffic as soon as any other links brakes.

Hope this help please include topology for more detailed response.