By a snowy evening, I just finished reading Postfix, the definitive guide, by Kyle D. Dent.

I have two regrets about that book:

  1. I haven't read it earlier.
  2. I don't own it.

This book answers most questions you have about Postfix, how to use it and how to configure it.

I first installed Postfix in 1999 to start replacing the old Sendmail on the FreeBSD boxes we were using as SMTP gateway to feed incoming mail to the e-mail system that was choosen. It is way easier to use than Sendmail as you don't have to learn the turing complete syntax of, and it fits the bill for 99% of the use cases (I still don't see the 1% missing).