Not sure if this should be here or in security but any how... I am a 'n00b' to Debian and Linux in general, I have got X windows running and various other programs with in Xwindows, but I want to know how to set up a firewall so I can close open ports and other things on my machine since I have a cable connection which leaves my machine vunarable to hackers.

Thanks people

You will need to learn how to use iptables.
For documentation and tutorials
Netfilter / iptables
http://www.netfilter.org/

However, if you want a GUI tool (which interacts with iptables), try one of the following:
http://firestarter.sourceforge.net/
http://www.shorewall.net/
http://www.ipcop.org/
http://www.fwbuilder.org/

If you dont want to learn about iptables, firestarter has a nice graphical interface to set up an iptables based firewall.

http://firestarter.sourceforge.net/

To install it just type; apt-get update
apt-get install firestarter

I just get the following message when I login to Firestarted "Child terminated with 1 status". Is there no window to configure it or anything?

-thanks.

I'm not sure if this has anything to do with Firestarter collapsing, but bear in mind that your kernel may not support iptables. If you're using kernel 2.2, you'll need to use ipchains instead.

OR, for the ultimate learning experience, you can learn to compile your own kernel.

Download the kernel source for 2.4.22 and put the .tar.gz file in /usr/local/src.
Unpack using tar -zxvf [filename]

cd linux-2.4.22

make menuconfig
(here, you configure all of the options you want in your kernel)
exit and save when done

make dep
make-kpkg clean
make-kpkg --revision=my.1.0 kernel_image
cd ../
dpkg -i kernel-image-2.4.22_my.1.0_i386.deb


If you boot up and get a panic, your probably forgot to include some drivers. You will need debian CD to boot up into the install, mount your drive, and get a root prompt. Then use dpkg -e to remove the old kernel and then reboot.