Classnotes | UNIX02 | RecentChanges | Preferences Postfix is a MTA (mail transportation agent) and is responsable for the delivery of mail on your system. It is an alternative to the widely used Sendmail MTA and is intended to provide the same functionality and similar interfaces.
Why not Sendmail?
Sendmail is perhaps the most commonly used MTA among UNIX systems. It is even the default MTA installed by Red Hat. However, Sendmail has many shortcomings.
It's very inefficient and requires a lot of system recourses to run.
It can be very insecure (rather, it can be very difficult to configure "correctly" to reduce security concerns).
It is very hard to configure.
Postfix is a "drop-in" replacement for Sendmail. It is much easier to configure and maintain, and is much more efficient.
Learning the intricacies of Sendmail is beyond the scope of this course. Postfix will provide you and introduction to the concepts behind a good MTA, and if you do have a need to learn Sendmail later what you will learn here will provide a good foundation.