Postfix is a widely used mail transport agent (MTA) used on many popular Unix/Linux systems. Nowadays, networks are overwhelmed by SPAM mail, fortunately, there is a way to filter them with software such as spamassassin.

1. Getting Started

By now, you should have a running SMTP server running postfix. There is a couple of package we need to install: spamassassin and its client spamc

$sudo apt-get install spamassassin spamc

spamassassin package includes a daemon which can be called by user programs such as procmail... but can also be integrated into a Mail Transport Agent such as postfix.

2. Using Spamassassin As A Standalone Daemon

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