Alexander Inzinger-Zrock via Mailman-users writes:
What logs? Everything under /opt/mailman/mm/var/logs:
- bounce.log
- debug.log
- mailman.log
- plugins.log
- smtp.log
All empty.
As Odhiambo says, since Mailman 3 is apparently running, mailman.log should have entries describing startup activities. You also wrote that messages were delivered via "mailman inject", in which case there should be various lookups in mailman.log and delivery notices in smtp.log.
Did you set var_dir or layout in mailman.cfg? If not, you may have an alternate var_dir which is either the current directory when you start Mailman or possibly /var/tmp/mailman. That is also where "mailman aliases" will put the postfix aliases (in the "data" subdirectory).
It might be a good idea to post your whole mailman.cfg and mailman3.service files to figure where Mailman thinks it lives.
-- GNU Mailman consultant (installation, migration, customization) Sirus Open Source https://www.siriusopensource.com/ Software systems consulting in Europe, North America, and Japan