Is this mesh configuration invalid?

I want to setup a mesh and started with two devices (wireless routers). Both running a recent Snapshot of OpenWRT. The current structure is shown in this diagram.

OpenWRT Mesh

There is a 802.11s mesh setup on each router for 2.4ghz (MESH) and 5ghz (MESH_5G). Additionally there are also corresponding APs configured on each device (WIFI and WIFI_5G). Also the networks are bridged so the LAN interface is configured as a bridge of the ethernet ports, MESH, MESH_5G, WIFI and WIFI_5G (IGMP snooping is enabled).

Everything works fine as long as there is only one of the mesh networks active. But if there is a connection of between AP1 and AP2 with MESH and also MESH_5G packets are lost and the network basically becomes inaccessible.

Is this configuration producing something like a circular reference within the network? If so, is it possible to prevent this of happening?

Yes it's invalid. You will have a bridge loop. Choose only one 802.11s link. If you want both up for resilience then enable STP on br-lan at both sides- then only one link will be active at any time.

What routers are you using? In principle your setup should work, of course, but there can be bugs in various implementations. Also, batman does more reliable routing than raw 802.11s in many firmware versions.
A good option is to buy a pre-configured setup like this one, rather than reinvent the wheel..

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To be more precise, 802.11s autoconfigures a layer 2 bridge network, similar to a virtual unmanaged switch.
Batman does exactly the same but adds on top its own layer 3 (IP) routing that can handle, cable interlinks amongst other things, over and above the basic layer 2 bridging.

My guess is Batman would have the same problems with this bridged setup.

Sounds interesting!

Thank you!

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