From GitHub 4 hours ago:
We are working on the issue to solve the root cause of the communication failures (more on it later today on the forum).
Also, my gateway lost its WiFi connection over an hour ago, and could not recover without cycling its power, like others have seen as well. Some observations:
I think it had been running for about 20 hours. (Certainly not a full day; I took a picture at 9 PM last night, when it was not connected; at around 6 PM today it showed as “Last seen: 54 minutes ago”.)
It might have been in AP mode (LED 2 flashing slow and fast).
Plugging in a debug cable with GND, RX and TX somehow restarted the gateway.
So to get serial output of a running device maybe only connect GND and RX, to lower the chances of an accidental reset? (Same when not using TX.)
The unexpected reset of the gateway did not resolve this.
After the reset, it kept reporting things like:
INET: Trying to connect to WiFi router again (after 120 seconds)
INET: State change to 0
MON: SYS Stack size: 3959
MON: heap usage: 148KB (148KB), free: 191KB
INET: No Ethernet and WiFi link (after 10 seconds)
INET: State change to 1
The FRITZ!Box 7360 WiFi AP did not log any connection attempts.
Restarting the WiFi AP did not resolve this. All other devices (Sonos, Apple TV, Chromecast, laptop, tablet, telephone) reconnected just fine.
Attaching an ethernet cable did not resolve this. The connector’s LEDs were flashing, but I forgot to check if the router showed a connection.
Finally cycling power resolved it.
I was surprised to see there was no GitHub issue yet, so here goes: https://github.com/TheThingsProducts/gateway/issues/8
I forget to check which LEDs on the PCB were on.