O'Reilly logo

Ubuntu Hacks by Bill Childers, Kyle Rankin, Jonathan Oxer

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

Hack #69. Protect Your Network with a Firewall

Protect your network with a firewall managed from your Ubuntu desktop.

Linux has an excellent kernel-based network packet-management system called iptables that can be configured either directly from the command line or through a variety of GUI administration interfaces. One of the most powerful firewall-management interfaces is called Firewall Builder, a system designed to separate policy from implementation and allow you to concentrate on what you want your firewall to do, rather than how you want it to do it.

The Firewall Builder interface presents hosts, routers, firewalls, networks, and protocols as objects, and allows you to drag and drop those objects to define your firewall policy. Firewall Builder then compiles your policy into the actual rules needed to enforce it, with multiple policy compilers available to suit different types of firewall. You can define your policy using Firewall Builder running on an Ubuntu desktop and then have it compiled for a firewall running iptables on Linux, ipfilter on BSD, or any of about half a dozen other firewall technologies. The policy can be defined exactly the same way, regardless of the technology deployed on the target firewall. And because Firewall Builder can support multiple firewalls simultaneously, you can use it as a central management console to configure a variety of firewalls and individual hosts throughout your network, all from a single, unified interface.

You can run Firewall ...

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