Thanks for the comments. I checked weewx.conf for all "loop" entries, no loop_on_init exists. So, by default, is it set to false? Shouldn't it be
generally
enabled for gw1000 driver?
I wonder, why weewx could not be started after exiting. To me, this indicates, that it was in fact still running in this status for more than 30 minutes. I could stop it, which took some seconds, and then start it again. At that stage the network was up and running, so everything worked well. As I reboot the Raspberry very rarely, next time I might have forgotten about this problem with the gw1000 and the Raspberry Pi after reboot. As the gw1000 itself is continuously running and sending the data without interruption to ecowitt, thus showing valid data on the WsView dashboard, I might not check, that weewx does not receive data then. I'm getting old....
If loop_on_init would also solve this issue, and additionally the problem of a temporarily missing network connection to gw1000, this would indeed overcome my solution with weewx.service, which only works at startup.
As the Raspberry Pi has to serve some other services (cups, home assistant, Unifi), I am not very happy with the idea to inspect weewx/gw1000 after repeated reboots. Especially, if I do not exactly know, which protocols have to be logged and evaluated. I could even assume, that at next time, the network might have started slightly faster, so this issue will not always be observable by chance. So, there should be a well defined environment for testing, which I currently don't have.
Meanwhile, before I forget about it, I will enable weewx.service modified with the Stanza mentioned above.
-Peter