June 2025
Beginner to intermediate
1180 pages
37h 48m
English
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26.7 SpamAssassin
Defense against spam is a battle against windmills that can probably never be won. In this section, I will show you how you can at least reduce the flood of spam by using the SpamAssassin program. SpamAssassin tries to decide whether an email contains spam or not based on various criteria. Reasons that lead to a spam classification include missing reverse DNS entries, obviously incorrect DNS details, or the origin of emails from known spammers—that is, from computers that have ended up on blacklists due to mass sending of spam.
SpamAssassin also takes the content of the email into account. The latter requires a relatively complex analysis, which causes a high CPU load on busy email servers. The results of the various spam ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.