Need to build a new mail server

[Jeffrey Goldberg]

On May 30, 2008, at 10:39 AM, DAve wrote:

> That so much time and effort is spent telling everyone how bad qmail  
> is still amazes me.

Is it still the case that qmail does not reject mail during SMTP  
transaction, but instead will do an "accept and then later bounce"?

If this is still true, then I don't care if qmail turns out to be a  
great way to manage your mail server.  It is a terrible network citizen.

Anyway, here are my personal prejudices about MTAs:

Sendmail:  There was a time when I would set things up for clients  
with sendmail because if I got hit by a bus, there were more people  
around with sendmail skills then exim skills.  Also there was a time  
when only sendmail did milters.  (And of course there was a time when  
there was only sendmail).  But my feeling about sendmail has always  
been that it was designed backwards in that things that should have  
been hard coded (parsing 822 addresses) were done in the configuration  
file and things that should have been configurable (throttling  
intervals) were hard coded.

For someone with a simple set-up using FreeBSD, sendmail may be the  
best choice still because it is already there.  Likewise for someone  
who wants to have their MTA to factor numbers or solve the towers of  
hanoi, sendmail is for them.

exim: If I were setting up a large complicated installation for say an  
ISP or a mail hosting system, exim is what I would use.  I've heard  
people say that they didn't understand the configuration file, but I  
don't see what the problem is.  It is straight forward and direct.   
You just need to remember that in some sections of the configuration  
file, the order of directives matter.  exim also has this built-in  
procmail replacement (exim filters) in its mail delivery.  Of course,  
sieve has largely replaced the need for this.

postfix: This would be my first recommendation to someone starting  
from the beginning for most sites.  If there is no legacy need for  
sendmail, and we are not talking about very large and complex  
arrangements requiring exim, then postfix solid, reasonably flexible,  
easy to set up and probably now has a user base to rival sendmail.

I have never managed a qmail, Lotus Notes or MS Exchange system.  But  
my MTAs have had to interact with them.  I feel that they should never  
be allowed to face the Internet.  They are just too loose in their  
interpretations of standards and conventions.

-j