Mailman Multidomain

[Ketil Kvifte]

I did spend a lot of time trying to get multiple domains kolab and multiple 
accounts mailman using the same domain names to work in December/January and 
when trying to figure out how to do it I looked around for clues. I had a lot 
of trouble configuring postfix so I did not get the error you are getting so I 
worked around it. 

I basically believe the pipe to command functionality in postfix does not work 
too well with multiple domains, which makes multiple domain mailman tricky. I 
think it's generally suggested in the postfix camp that we use master.cf 
instead if we want to use it for multiple domains, but please correct me if 
that is not postfix's official statement. It has been a long time since I did 
this so I don't remember where I got that information any more. Mailman2 is 
not made to work well with multiple domains, but mailman3 will be better in 
that regard as it support lmtp instead of relying on piping and generally 
handles multiple domains better. I have not tried mailman3 yet as it's still 
only preview and doesn't have any stable release, but the feature list does 
look good.

Debian-based distributions tend to recommend using mailman with the 
postfix2mailman.py script so I ended up using it. It uses the master.cf instead 
of pipe-to-command in aliases. I use CentOS which did not come with the script 
bundled so I copied it from an ubuntu install I had available. 
postfix2mailman.py is rather easy to setup and is generally used by forwarding 
all mailman email to a special domain where every mail is delivered to that 
script through /etc/postfix/transport and /etc/postfix/master.cf. There are a 
lot of guides how to configure it on the Internet. I am not sure if doing it 
this way is the good way, but it was the only way to make multi domain mailman 
work with multi domain postfix that I could figure out when working on it. 


Ketil