I've spent more time than I care to admit trying to configure Mailman. And I almost have it all working now, but I just can't seem to get my Mailman/Postfix combo to receive emails.
When I try to send emails to lists I'm rebuffed with undelivered notices with:
<testlist(a)lists.fiftyshadesof.green>: Host or domain name not found. Name service error for name=lists type=AAAA: Host not found
<testlist(a)lists.fiftyshadesof.green>: Host or domain name not found. Name service error for name=lists.fiftyshadesof.green type=MX: Host not found, try again
This to me appears to be an issue with my DNS settings, but I can't work this out either. I have an A record for lists.fiftyshadesof.green pointing at my server, and an MX record pointing at that:
lists.fiftyshadesof.green. 0 IN MX 0 lists.fiftyshadesof.green.
lists.fiftyshadesof.green. 0 IN A 18.104.22.168
I have driven myself mad with this and would very much appreciate any advice anyone can offer.