Is there a mistake here ? from http://tldp.org/HOWTO/Firewall-HOWTO-7.html

5.1. Selecting a Kernel [...]

The bilt in Linux firewall have changed several times. If you are using an old Linux kernel (1.0.x or older) geta new copy. These older used ipfwadm from

and is no longer supported.

Speeling errors are in the original document. Also,

1. IP filtering setup (IPFWADM)

If you are using kernel 2.1.102 or newer skip to the next section on IPCHAINS.

Actually, both of those lines are wrong, but why are you looking at a firewall tool that has been virtually unsupported for over six years, and does not work in a 2.6.x kernel.

Yes, and there are other errors as well, but unless this is a homework question, you should be reading the IP-Masquerade-HOWTO (even the IPCHAINS-HOWTO is outdated), and also looking at the materials you can find on

or which actually redirects to the netfilter.org site.

Old guy

thanks.

I was just doing some general research on firewalls when i came across this article.

I was a bit puzzled by that line as just wanted to make sure it was wrong,

I dont use a Linux firewall , i use a netgear .

Ahh, OK. The Linux Documentation Project has a large number of documents concerning "how to" do a number of important (and not so important) tasks using the Linux O/S. You can find a description of them by searching for the "HOWTO-INDEX". You can find a "current" tarball of the 450+ documents (about 30.5 Megs uncompressed - 692K lines, 3.8 million words) at the ftp/web server 'ibiblio.org' in the /pub/Linux/docs/HOWTO/ directory (as well as individual copies of documents). A cron-job tells me this looks like this:

7106026 May 18 09:01 Linux-HOWTOs-20070518.tar.bz2 8879237 May 18 09:01 Linux-HOWTOs-20070518.tar.gz 29 May 18 09:02 Linux-HOWTOs.tar.bz2 -> Linux-HOWTOs-20070518.tar.bz2 28 May 18 09:02 Linux-HOWTOs.tar.gz -> Linux-HOWTOs-20070518.tar.gz

That document is a bit over seven years old and probably unmaintained, but I was surprised of the number of typ0s, concept and speeling errors it contained. The docs are normally much better than that.

For _concepts_ (along with examples), I'd strongly recommend the 'netfilter.org' site mentioned above ("Rusty Russell" is the main author of the current firewall code, although many others contribute) and is a pretty decent author. Other documents (HOWTOs) that would help (or be of interest) are:

-rw-rw-r-- 1 gferg ldp 708351 Nov 14 2005 IP-Masquerade-HOWTO

-rw-rw-r-- 1 gferg ldp 17605 Jul 21 2004 Masquerading-Simple-HOWTO

-rw-rw-r-- 1 gferg ldp 45604 Apr 18 2006 Networking-Overview-HOWTO

-rw-rw-r-- 1 gferg ldp 155096 Jan 23 2004 Security-HOWTO

-rw-rw-r-- 1 gferg ldp 278012 Jul 23 2002 Security-Quickstart-HOWTO

At home, the firewall is what's left of some ancient 386SX-16 laptop, without case, keyboard, or display. It's more than adequate for a cable connection, and also has a modem for dialout as a backup.

Old guy

thanks dude

enjoy your weekend