I have a qbittorrent container set up with the docker UI on my Synology NAS. The synology webstation (frontend for nginx, I think), allows my subdomain to point to the webUI. Turning the container off and on on the toggle of docker works but I get a 502 error after rebooting the NAS when I try to connect to the webUI, which forces me to manually stop and start the container again. It works after the manual restart.
I would show the logs but they all work as expected: both the reboot and the stopping show that the SIGTERM signal was captured and after the restart of the container, the normal logs are shown.
What could be going on?

502 means the proxy can’t reach the proxied application. That says, we use our own reverse proxy solution here (swag) so I’m not sure you will find much help here.

If you’d like some help swapping to swag, take a look at our guide