RSTP root on remote Meraki MS series switches

[SteveLandon]

I have a central main facility with numerous Meraki switches. The RSTP settings are correct and the core switch is root. Five other locations ae connected to this main via VPN . What switch should be the Root for the remote locations?

[rhbirkelund]

Spanning-Tree is a L2 feature. It is not extended over VPN. Each of the 5 locations will probably be their own RSTP root.

[KarstenI · Accepted solution]

@rhbirkelund has your setup covered with a 99,9% likelihood. But if you have ordered L2VPNs from your ISP and you share subnets between the HQ and the remote branches (which you really shouldn't unless you *really* know what you are doing) that your HQ likely should keep the root and all branch switches should have an inferior priority.

[SteveLandon]

You're right. Branch locations have their own root priority. I also found a problem in a branch location that had been ignored - now fixed. Thanks for your help. Steve

[SteveLandon]

We are using Sonicwall boxes for firewall/vpn. Nothing from ISP except fiber circuit. In some locations I have more than 1 access switch. I also have several old Cisco SG200 remotely that are going away soon. It looks like 1 of those SG200 have made itself rstp root. None of this was an issue until lately network congestion and slow down started for no obvious reason. I did find a small 8 port Meraki that had taken over as root and I fixed that last night. Improvement. I inherited this and now I'm cleaning it up a bit.  I'll try a fix on one of the remote locations tonight after hours.

[KarstenI]

well, with that every branch has it’s own spanning tree and there is no need to look at it across the branches. Yes, cleaning up is always a good idea.