Michela via Mailman-users writes:
The log file, /opt/mailman/web/logs/uwsgi-error.log, contains the following stack trace, however. Note the bit toward the bottom: "ModuleNotFoundError: No module named 'settings'"
Given that you can run the applications from the command line as systemd services, this almost certainly localizes the problem to uwsgi itself. Note that uwsgi has been problematic lately. I don't recall the details. I think there's a preference for gunicorn as the SGI provider among the Mailman 3 developers (and it's what core uses internally to provide the REST interface) so uwsgi may not get "beta" testing in production from us.
Specifically, is this line
pythonpath = /etc/mailman3/present, correct, and not commented out in uswgi.ini?
My configuration files outside of the Mailman virtual environment are in /etc/mailman/:
Is it possible you have /etc/mailman/ instead of /etc/mailman3/ in uwsgi.ini as in the above quote? (I am pretty sure that's a typo in the post, but gotta check everything.) On the other hand, maybe we did a typo, and there should be no trailing slash on /etc/mailman3 in this statement. (Usually trailing slashes aren't a problem, applications mostly ignore them, but there is no trailing slash on any directory in my sys.path, so it's worth a try.)
If it's none of the above, I'm out of ideas. Maybe Mark or Abhilash has more experience.
Steve