June 2025
Beginner to intermediate
1180 pages
37h 48m
English
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29 Firewalls
The title for this chapter is a bit striking—simply because everyone associates something different with the term firewall. In fact, this chapter is not only about filters for network packets, but also about network basics and about other techniques for securing them. You will first get to know some fundamental tools to analyze the current status of the network—for instance, to find open ports. A section on the TCP wrapper library shows you how to restrict access to some network services using simple rules. I will then introduce you to firewall configuration tools and the nft command of the new nftables firewall system.
29.1 Network Fundamentals and Analysis
Before you can secure your computer, you need to get an idea of how ...
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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.