Hi,

I'm using a Mandriva 2006 edition and I have bot iptables and shorewall installed.
I was wondering what's the difference between them ? Can i use shorewall w/o iptables and vice-versa ?
How are they related to Netfilter ?
Both of them are installed in services : shall I turn them on at startup ?

Thanks in advance.

The actual low-level mechanism that the kernel uses to filter packets is "iptables." (There was an older version called "ipchains" that isn't used anymore.)

Products like ShoreWall are simply power-tools for quickly building appropriate sets of iptables rules. The mechanisms provided by Linux are fairly cryptic, and products like Shorewall make setting up the desired configuration much easier. (Furthermore, the resulting firewall will be a lot "smarter," since very-experienced people set up those rules files so that the rest of us can simply benefit from their expertise.)

Note: If you have both a service named iptables and a service named shorewall enabled at the same time, you probably don't want/need to do that. You'll find that both of them build and issue iptables-rules, and you do not want them to conflict, because in doing so they might weaken or screw-up your firewall. Choose one or the other; I suggest shorewall.

You said that the low-level mechanism that the kernel uses is iptables but suggest to use shorewall instead ! There's something I don't understand...

Any reply ?

i never use shorewall, but according to sundailsvc , shorewall just a tool for ease of using iptables. It itself isn't provide much (if any) protection. Its like you can use note pad and frontpage to write html, only later ones is much easier.