O'Reilly logo

Troubleshooting Linux® Firewalls by Michael Shinn, Scott Shinn

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Chapter 6. netfilter and iptables Overview

The first thing to get out of the way is that netfilter and iptables are not the same thing. They are largely written by the same group of developers, but they are very different parts of a whole. netfilter comprises the kernel level code that Linux can use to conduct packet filtering, state management, NAT, packet mangling, QOS, and other neat tricks. iptables is the userland tool that can manipulate these kernel hooks to do these things for you. It’s important to point this out because there are other userland tools that use netfilter as well and that also can accomplish some pretty neat tricks.

How netfilter Works

With this bit out of the way, we can move on with the discussion of how netfilter works. ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required