Here in upstate New York, USA, I'm having difficulty with 2 meshes, each with 4 nodes, both meshes running BATMAN_IV. All nodes are TP-Link Archer C7 or A7 routers running the latest OpenWRT trunk. All nodes are stationary.  The radio environment is pretty quiet, I think.  There is only one gateway in each mesh.  Nothing ever changes.  (A map of the layout can be found at rosepark dot us hash map.)

Nevertheless, each mesh stops working at least once or twice per day.  If I reboot the gateway node of the one that stops working, the mesh starts working again.  In order to keep the meshes running, sort of, they now run a script I wrote that reboots them when they stop being able to ping each other.  It is not a very satisfactory solution.  If I could see what's going on, I might see how to make the meshes more stable, but I can't find any debug messages.

I compiled batctl-full and the kernel module with all options, including all debug options.  Here's a portion of a "make menuconfig" screen:

<*> kmod-batman-adv......................................... B.A.T.M.A.N. Adv [*]   B.A.T.M.A.N. V protocol [*]   Bridge Loop Avoidance [*]   Distributed ARP Table [*]   Network Coding [*]   Multicast optimisation [*]   batman-adv debugfs entries [*]   B.A.T.M.A.N. debugging [*]   batman-adv sysfs entries [*]   B.A.T.M.A.N. tracing support

I run "batctl ll all" followed by "batctl ll" and I see:

@rpc152:/tmp/log# batctl ll [ ] all debug output disabled (none) [x] messages related to routing / flooding / broadcasting (batman) [x] messages related to route added / changed / deleted (routes) [x] messages related to translation table operations (tt) [x] messages related to bridge loop avoidance (bla) [x] messages related to arp snooping and distributed arp table (dat) [x] messages related to network coding (nc) [x] messages related to multicast (mcast) [x] messages related to throughput meter (tp)

But the only debug-related log messages I see are:

@rpc152:/tmp/log# echo "$(dmesg)" | grep batman [   18.672978] batman_adv: B.A.T.M.A.N. advanced 2019.5-openwrt-0 (compatibility version 15) loaded [   42.067698] batman_adv: bat0: Adding interface: mesh0 [   42.073065] batman_adv: bat0: The MTU of interface mesh0 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would \ solve the problem. [   42.098069] batman_adv: bat0: Interface activated: mesh0 [174193.938445] batman_adv: [Deprecated]: batctl (pid 22747) Use of debugfs file "nc_nodes".

@rpc152:/tmp/log# echo "$(logread)" | grep batman Thu Feb  6 15:21:13 2020 kern.warn kernel: [174193.938445] batman_adv: [Deprecated]: batctl (pid 22747) Use of debugfs file "nc_nodes". @rpc152:/tmp/log#

What have I missed?

Thanks.

Steve Newcomb