We are looking at replacing sendmail and I am just having a bit of a play with postfix.
I setup postfix and mailman on a test server and managed to get a basic setup to go.
One of the things I did notice is that when I send an email to one of my lists it appears
as mailman@it012345.mydomain.com. I would like it to appear as mailman@lists.mydomain.com

My hostname on the server is set to lists.mydomain.com and I have set it to the same in
my postfix main.cf file and mailman’s mm_cfg.py file

In the DNS the machine has a hostname of it012345.mydomain.com and its alias is called lists.mydomain.com.
Changing this the other way around could fix but that goes against our policy.
Is there a way I can achieve this through postfix?