Firewall help

[boilerhouse]

Hi all
I have been running Kubuntu Breezy with KDE 3.5 with Firestarter and connecting to the internet through a Belkin ADSL modem with built in wireless router (firewall protection inbuilt) for a couple of weeks now. I have had no problems with connections, and Firestarter has run smoothly.
I recently added the following to the /etc/apt/sources.list :-

deb ftp://ftp.nerim.net/debian-marillat/ sarge main
deb ftp://ftp.nerim.net/debian-marillat/ etch main

and installed java then installed as explained on another post in this forum. Then installed Azureus, everything loaded fine.
I made changes to Belkin for the ports 6881 and then also for Firestarter, then ran the connection test from Azureus, the test stated it failed. Ever since then Firestarter wont allow connections out, I have deleted Azureus and Firestarter.
Deleting Firestarter and then re-installing after removing all Firestarter bits from the folders did not sort the problem.
My first question is, if I have already a firewall built into the Belkin do I also need to run a software firewall also? Another question is has anyone else had the same problem occur?
Any help on this matter would be gratefully appreciated!
Stephen

[RenegadeAbe]

Re: Firewall help

My first question is, if I have already a firewall built into the Belkin do I also need to run a software firewall also?

Heres my 2 cents on the subject:
In most all computer related functions any hardware implementation will far outweigh any implementation of a software counterpart.
hardware RAM will always be better than Virtual RAM
same logic applies for the Firewall.
That said, I guess it doesnt hurt to be extra cautious.
In your case, Firestarter combined with the Belkin would certainly be a viable option of network security.

My only beef with that solution is that you would have to wrestle with two firewalls rather than one (pros and cons will of course arise from this) and therein lies the problem; because of this setup, you may encounter multiple problems when trying apply a simple rule and the diagnostic would be hell.

I guess for me, one very well defined hardware firewall would suffice; but then again this is only because Im on a home network with 2 PCs. Had it been a networked domain of multiple users with different security clearances then of course my opinion would be vastly different

Another question is has anyone else had the same problem occur?

Sorry I dont use firestarter but here's a thought that may help you.
Remove Firestarter first and install Azurues.
Make sure that Azurues work with your belkin (It passes the test)
[Download something small and verify that you get it to work]
- Now at this point once you reinstall firestarter and Azurues stops working then you know where the problem is; and you localize your diagnostics in firestarter.

Good luck!

[boilerhouse]

Re: Firewall help

RenegadeAbe
Thank you for your reply!
Azureus reported NAt failed, so I must look again at my Belkin setup again.
I take on board your comments. Having run a test through www.grc.com on the firewall system on Belkin only, it comes back stealth which is good.
I suppose I am concerned what caused Firestarter to start acting as it did, wonder what other configuration has changed?
Ste

[jferrando]

Re: Firewall help

I think the best linux firewall is the kernel-included iptables.
Just a little complex the first moment, but it is totally robust, and there is plenty of documentation in the net.

[BlindEye]

Re: Firewall help

I think the best linux firewall is the kernel-included iptables.
Just a little complex the first moment, but it is totally robust, and there is plenty of documentation in the net.

If iptables is a little too intimidating at first, there's also Shorewall.

The Shoreline Firewall, more commonly known as "Shorewall", is a high-level tool for configuring Netfilter. You describe your firewall/gateway requirements using entries in a set of configuration files. Shorewall reads those configuration files and with the help of the iptables utility, Shorewall configures Netfilter to match your requirements. Shorewall can be used on a dedicated firewall system, a multi-function gateway/router/server or on a standalone GNU/Linux system. Shorewall does not use Netfilter's ipchains compatibility mode and can thus take advantage of Netfilter's connection state tracking capabilities.