Firewall/Router

[Warren Togami]

Redhat 7.1 makes it very easy to make an Netfilter/iptables firewall.  Its
2.4.2 kernel works "out of the box", when using iptables rules for IP
masquerading.  I'm currently using it at home to do stateful IP masquerading
for several machines in my house.

You need NO SERVICES to run a secure Netfilter firewall/router, although I
suggest running SSHd for remote administration.  That's the only thing I
run.

All you need to do is enter Linuxconf and configure:
eth0 DHCP
eth1 IP 192.168.0.1
Subnet 255.255.255.0

Mon Motha's IPTables script
http://bjpscsci.ath.cx/~monmotha/firewall/index.php
I use this script with a few minor modifications

Basic Steps
1) Download latest 2.3.6 version, even though it is the unstable series.
I'm currently using 2.3.5 with no problems.  Make sure that you download it
without the web browser mangling the line breaks and formatting.  wget works
well for this.
2) Change IPTABLES="/sbin/iptables"
3) Don't add TCP and UDP ports unless you need them.
4) INET_IFACE="eth0"
5) LAN_IFACE="eth1"
6) USE_SSH1="FALSE"
7) USE_OPENSSH="TRUE"
8) comment out exit 99

Then run the script.  It should work.  If not, try 2.3.5 (I'm currently
using it with default Redhat 7.1 install).

On the clients configure IP's between 192.168.0.2 and 192.168.1.254
inclusive, gateway 192.168.0.1.
DNS servers are the same, because it will route DNS requests with no
problems.  My RR DNS servers are 24.25.227.34 and 24.25.227.36, I don't know
if you have the same.

Some of the more advanced options in Mon Motha's script are very easy to
configure once you read the description.  Once I was leaving the house, when
I realized I wouldn't be able to access my desktop via VNC from school.
Took me 3 minutes to figure out the syntax for port forwarding in the
script.

If you need any help please post again.

----- Original Message -----
From: "Julio Gutierrez" <gutierrej001 at hawaii.rr.com>
To: "Linux & Unix Advocates & Users" <luau at list.luau.hi.net>
Sent: Thursday, April 26, 2001 1:31 PM
Subject: [luau] Firewall/Router


> I'm trying to setup a router/firewall for my little network,
> and I think I need help finding out what daemons I need in order to make
it
> work, I don't need any graphical desktops or even X I want to
> administer from console.
> I'm trying RH 7.1 because is the only distro I've been able to setup & run
on
> this PC, this is a P75 IBM 64MB RAM 514MB HD.
> can someone can lead me in the right direction or tell me how to do this?
> your help will be greatly appreciated!!!
>
> Julio