Im trying to configure a firewall with a linux box and two windows box on a network behind a linksys router. I want the linux box to control the packet flow in and out....is this possible? the linux box has only one eth card so i cant use masq and im a newbie to iptables. can someone help or at least point me in the right direction?

hi there

use shorewall
iptables based firewall
shorewall.net

quite simple working

regards

so you dont edit the files directly?? i thought there was just a configuration file that u edit.

is there a way to edit these files directly? I kinna wanted to learn how to script the iptables myself.

no i do not edit the iptables script directly
that will take altogether take some good time

instead shorewall generates
u can also edit that directly

for that have a look at the HOWTo's available for iptables firewall at tldp.org

regards

I'm not exactly sure how you can have the Linux box do the firewall for your whole network without using it as the router. You could use it as an IDS box and then at least you would know and there are some controls. For that I would reference http://www.internetsecurityguru.com/. It is specific to FC2 but you would get the idea. If you want some documentation on iptables, try http://www.netfilter.org. That should give you some places to start. If you want to take a leap of faith, you might try replacing the Linksys with a Linux box, using it as a router and running IDS. Then you would be able to play with the firewall, get alerts when someone is trying to get in and learn a whole bunch in the process. You would not need a big fancy box to do this with . Even an old 486 or equal would work. If you are using the Linksys to do PPPoe to connect to your ISP the nix box would do that just fine. Good luck and repost when you get a chance.

I too agree that ur linux box can be the FW of ur network if it is the router/interface to the internet for ur network

regards