Linux Tutorials on the topic “postfix”


What is Postfix?

Postfix is a free software (IBM 1.0 License) mail transfer agent tool that was originally written in 1997 to server as an easier to use and more modern alternative to the widely used Sendmail, which is also open source. According to credible studies, Postfix is used by roughly one out of three mail servers on the internet. Postfix features a high-performance parallelized mail delivery engine that works on every Unix-like operating system such as BSD, GNU/Linux, OSX, HP-UX and Solaris. The fact that it is currently the default mail transfer agent in Ubuntu, NetBSD and Apple's OSX highlights its superior operation and design quality with a rich set of features.

Postfix can deliver hundreds or even thousands of mails in one instance thanks to its parallel session abilities, whereas Sendmail only makes one connection at a time. Moreover, Postfix basis its operation on a pipeline process methodology. This basically means that information for message delivery and/or error notifications are passed from one process to the next one, and when a process fails the action is retreated to the previous and is re-tried later. This approach makes Postfix a robust and reliable solution that can only really be undermined by hardware failures.

The software boasts sophisticated Junk mail control features such as postscreen zombie blocker, greylisting, content filters, concurrency limitation and address probing callout. The protocols that are supported by Postfix are RFC 6531-6533 Email Address Internationalization, configurable DNS reply and delivery status filtering, HAproxy, Nginx proxy, DSN status notifications, Cyrus and Dovecot, IPv6, TLS encryption and notification, MIME, ETRN on-demand relay, LMTP client, SASL authentication and QMQP server. The database lookup support includes DBM, Berkeley DB, MySQL, PostgreSQL, CDB, SQLite, Memcache, Sendmail-style socketmap and finally LMDB.

Postfix is also pretty much extensible as it can seamlessly work with other popular spam/virus filtering and message store access software tools. The most typically used extensions concern mail authentication with DMARC, DKIM and SPF, policy accessing control and deep content inspection before mail distribution.


HowtoForge and Postfix

HowtoForge's rich content database includes many useful guides on how to enhance the performance and security features of Postfix. You may find clever and easily applicable ways on how to improve your spam abuse protection mechanisms, how to use Dovecot with Postfix, how to handle virtual users and domains with the software and how to set it to lookup MySQL databases. There are many entry-level tutorials written for Ubuntu, Debian, Suse and CentOS users like how to authenticate against active directories and how to install and configure Mailman in Postfix, while there are also some more advanced ones that show how to build a fully featured mail server with Postfix on Gentoo, or how to “harden” Postfix for ISPConfig 3.

For whatever you may not find in the tutorials section, you can always visit our forums and ask for the advice of the expert and helpful community of web administrators. Thanks to the popularity and the large user base of Postfix, it is almost certain that you won't have to wait for to long for a helpful answer, no matter your issue.