Sascha Rissel writes:
I wonder a bit how deep I have to dive into these individual configuration files. Is there some minimal config for a standard Ubuntu/Debian system?
I think that if you follow the "venv" process as described in <https://docs.mailman3.org/en/latest/install/virtualenv.html?>, it covers everything you must configure. There are about a dozen places that you must check in mailman.cfg, such as the location of your MTA and its port (for the simplest installations, host=127.0.0.1, port=25 will do), mailman's LMTP port (usually the default of 8024 will do), and the credentials for accessing the REST interface (restadmin and restpass: change these!!) Pretty sure there are others. There are quite a few decisions that need to be made in mailman-web settings.py, including setting the REST credentials to the ones you chose in mailman.cfg, and setting up your database (sqlite3 is great for quick experiments or tiny installations with 10 posts/year ;-). And I don't think there are any MTAs or webservers that are plug and play with Mailman: you have to configure the MTA to forward mailman list addresses to Mailman's LMTP port, and usually there's nontrivial configuration of the namespaces that are to be forwarded to Mailman/Django and those that are served directly (such as CSS style files) by the webserver. Django also has its own access credentials that must be coordinated with mailman.cfg I think.
So "minimal" is still pretty complex.
While I would be *extremely* cautious about using any *values* for parameters that are specified in Brian Carpenter's HOWTO <https://wiki.list.org/DOC/Howto_Install_Mailman3_On_Debian10> (this is the one that Odhiambo suggested, and it's a really valuable resource), I'm pretty sure it accurately covers all the steps you need to take in configuration. You may find it easier to read than our manual. Going through that and checking your venv configuration against the steps in the HOWTO would be a good way to confirm that you've got a good configuration.