Hello Mailman users,
I've been using Mailman2 for 10+ years and have recently upgraded to Debian Buster with Mailman3. I've tried to setup Mailman3 similarly but it fails to deliver emails sent through a list. I do receive all moderation notifications at the same time.
During startup /var/log/mailman3/mailman.log receives:
Cannot connect to SMTP server localhost on port 25
but I've made sure postfix is listening on *:25 for both IPv4 and IPv6.
When sending a message to a list the same file receives:
Nov 25 11:38:14 2022 (70371) ACCEPT: <MESSAGEID@HOST>
(message ID and host redacted) and nothing else happens: no more log messages, Postfix logs the email sent TO Mailman but doesn't log anything about emails sent BY Mailman.
If Mailman fails to send emails via Postfix I'd expect it to log error messages but it doesn't seem to do so.
I found this article stating the the SMTP error message might be misleading: https://blog.tfiu.de/mailman3-cannot-connect-to-smtp-server-localhost-on-por...
How to further debug this? What could be wrong with my Mailman3 instance and how to fix it?
Kind regards Daniel Böhmer