i observe a limit of 127 interfaces which can be hooked into bat0 where do i find this limit, or does somebody can tell me more about this? Or, if it is a good idea to circumwent this at all? Or, if its even possible in actual protocoll structure.
background: Freifunk with tunneldigger and l2tp tunnel interfaces put a whole lot of l2tp-eth interfaces in a bridge and hook the bridge into batman, which make trouble and also doesnt feel like good practice. (i think to circumvent this limit)
Freifunk with wireguard and gretap also have a lot of gretap tunnel interfaces - but without bridging is limited to 127 interfaces (we also experiment with vxlan which is limited to v4 in bridge forwarding and by this not really an option - idea was to hook vxlan0 in bat0 , which may be similar to bridging l2tp-eth)
you can find the test here (in german) https://forum.freifunk.net/t/500-gretap-tunnel-interfaces-in-batman-einhaeng... or the wireguard in freifunk structures (batman network) here https://forum.freifunk.net/t/wireguard-0-0-20161230-mit-linux-3-18-kernel-un...
the error if you exceed the interface limit in dmesg :
|Error - can't write to file '/sys/class/net/gre127/batman_adv/mesh_iface': Cannot allocate memory|