Thanks to David and everybody else that have replied to my problem. I have proceeded to uninstall the debian mailman3 packages and then endeavored to install everything with venv. I have implemented all of David's configuration suggestions which were very helpful. Now, mailman3 (core) appears to be working properly in that I can start/stop/restart/status the service. Also, the command "mailman info" from the venv prompt yields output which appears to be correct and the same as in the venv instructions. However, I have not been able to get mailman3-web working.
All of my configuration files may be viewed here:
https://dickens.com/etc-mailman3/
The above files are basically a mirror of the contents of my /etc/mailman3 directory except that I have obfuscated sensitive info such as keys, passwords and email addresses.
Executing the mailman3-web service script with the command "systemctl start mailman3-web" starts everything without errors, however, the command "systemctl status mailman3-web" then generates the following output with errors:
● mailman3-web.service - GNU Mailman Web UI Loaded: loaded (/etc/mailman3/mailman3-web.service; enabled; vendor preset: enabled) Active: failed (Result: exit-code) since Tue 2022-01-25 17:10:30 EST; 6s ago Process: 1718478 ExecStart=/opt/mailman/venv/bin/uwsgi --ini /etc/mailman3/uwsgi.ini (code=exited, status=1/FAILURE) Main PID: 1718478 (code=exited, status=1/FAILURE) CPU: 12ms
Jan 25 17:10:29 slc.mailhub4u.com systemd[1]: Started GNU Mailman Web UI. Jan 25 17:10:30 slc.mailhub4u.com uwsgi[1718478]: [uWSGI] getting INI configuration from /etc/mailman3/uwsgi.ini Jan 25 17:10:30 slc.mailhub4u.com systemd[1]: mailman3-web.service: Main process exited, code=exited, status=1/FAILURE Jan 25 17:10:30 slc.mailhub4u.com systemd[1]: mailman3-web.service: Failed with result 'exit-code'.
Also, /var/log/syslog and "journalctl | grep mailman3-web" contain these two lines of errors:
Jan 25 14:00:46 slc systemd[1]: mailman3-web.service: Main process exited, code=exited, status=1/FAILURE Jan 25 14:00:46 slc systemd[1]: mailman3-web.service: Failed with result 'exit-code'.
Also, other commands in the venv instructions do not work such as "mailman-web migrate" which produces volumes of error dialog starting with:
Traceback (most recent call last): File "/opt/mailman/venv/lib/python3.9/site-packages/django/template/utils.py", line 66, in __getitem__ return self._engines[alias] KeyError: 'django'
Then these two lines are then followed by over 50 lines of django and python error messages.
I have not been able to find any hints or suggestions as to what I am doing wrong in my server's logs. FWIW, I have been working in the Unix/Linux command line environment for over 35 years and I have extensive LAMP, EXIM and Mailman2 experience. However, I have not ever worked with Django. I am usually able to resolve issues like this quickly, however, I am at a total loss as to what to do now with this mailman3 installation. I suspect that my unfamiliarity with Django may be my achilles heel.
So, I am hoping that somebody here will soon be able to offer suggestions that might help me get everything working properly. I have several organization's mailings lists on this server and I need to get this fixed ASAP especially since my mailman installation has been down now for almost 3 weeks. As you might imagine, this is causing me alot of grief with my mailman3 users. So, please let me know any suggestions that you folks may have to get my mailman3 installation working again.
Many Thanks,
Gordon