I recently purchased two Cisco Meraki routers. I had some old netgear non-managed switches that I thought was causing my looping problem, so I went out and bought what I thought at the time was a new managed switch. It turns out that it's considered non-managed, but it does get its own IP, and there's some configuration that can be done. I picked a Netgear GS108EV3 ProSafe Plus switch because it had loop detection. I enabled the loop detection, and plugged both Merakis into it, and could tell right away that it was doing the same thing as the other old switches where the lights would flash very quickly, and basically disrupts the whole network. I figured with this new switch that the loop detection was Spanning Tree Protocol, but that may or may not be the case. Not sure if I need a true managed switch for this or not. I've seen posts on the internet where people have used STP with a non-managed switches, so I think what I'm trying to do isn't out of the realm of possibility. Not sure what I'm doing wrong, so any help is greatly appreciated.