[TriLUG] Postfix v QMail ?

[Aaron S. Joyner]

Craig Duncan wrote:

>Looking for some real world feedback on using these MTA's, whether one
>has an advantage over the other, scales better, etc.
>  
>
Let me start by saying that I have little experience with QMail, but
have a healthy respect for it's security track record, and my
familiarity ends with it's lack of a "sendmail" style interface (meaning
you can't call /usr/sbin/sendmail exactly the way so many programs expect).

Postfix, on the other hand, is an exceptionally good MTA.  I started
using it probably 3 years ago now, and haven't looked back once.  Prior
to that I'd used sendmail in home, research, ISP, and numerous other
environments since the mid 90s, and was quite comfortable with it.  I
was sort of "forced" to learn postfix at one point, and am so thrilled
that I was.  It has a laundry list of good features, but I'll just hit
the highlights real fast.  Individual daemons to handle individual tasks
- great security feature that has led to a very good security track
record, and also eases the understanding of some unusual
configurations.  Very easy configuration for both simple, and highly
esoteric uses - Postfix makes the easy things easy, and the hard things
easy.  :)  Easy and efficient integration (via Amavisd-new) with Spam
and Virus scanners, as well as easy drop in greylisting that requires
very little configuration to properly implement.  A very intelligent
spool setup which makes figuring out where your bottle necks are very
quick and easy.  I could go on and on...

In short, I've run mail systems that process (on average) upwards of 1.5
million messages per day through two postfix boxes, doing virus and spam
scanning, and having some breathing room, with just two postfix boxen
(the secondary box was comparatively idle).  I can't compare it's
scalability with QMail, but I can say that it's scalability is very good
- likely well beyond what will matter for most people's purposes.  :) 
As an added bonus, tuning postfix to work well in our environment was
actually quite easy.  Adjusting the number of daemons waiting for
connections, how fast those daemons are killed off after a burst of
traffic, etc is all very easy.  Integrating with unusual setups (think
things like Radius, MySQL, LDAP, etc as user repositories) is all very
convenient and easy as well.

Anyway, if you choose QMail and prefer it, let us know why!  :)  If not,
let us know what tipped you towards Postfix, and what you liked most
after you started using it.

Aaron S. Joyner