This is the best book on the subject. Ralf is frequently on the postfix-members mailing list, and he's the kind of guy who's always open to learning new things about an area where he already has a lot of experience, as well as sharing as broadly as possible the experience that he has gained thus far.

Ironically, O'Reilly is the US distributor for No Starch Press, and their best-selling book on postfix is this one, not their own by Kyle Dent.

Look for a new edition to come out in 2008. ( )

Highly recommended, well written. If you have to tweak your companies postfix mail server, get this book, it will pay for itself many times over. ( )