Join requests are never accepted

[imilne]

This took way too long to get to the bottom of, but we at least know now what’s wrong - basically, the MQTT forwarder on our gateways is not compatible with ChirpStack 4:

Help testing ChirpStack v4 (test releases)!

Let me start by saying I’m not sure who I should be bringing this report to (RAKWireless vs. here). I decided to start here because Chirpstack v4 docs indicate that the v3 gateway bridge should work with Chirpstack v4 in protobuf mode—Am I correct in understanding that backwards compatibility with protobuf formats is expected? Our problem: We have many RAK7289 gateways running the WisGateOS. I don’t believe–but don’t know for sure–that WisGate uses chirpstack-gateway-bridge internally; however,…