Hi all.

I have little problem with my Redhat 7.3 machine.
I try to make my linux box that allows internet sharing
to my local-network.

I use iptables and here is what i do.
I type this line:
#iptables -t nat -A postrouting -o eth0 -j MASQUERADE

and it gives me this:
iptables: No chain/target/match by that name

what is wrong ?? Same command works at my
friend computer.

Thanks

-- Krisse

Do you have the NAT chain set up in your kernel?

You might want to check out something what is on:
http://www.citadec.com/FirewallGenerator.html

It seems to be a Java applet what asks some questions and generates a firewall shellscript from your selections. (it has masq option also)

Its good to read what it does, but it helps to get started.

A couple of things...

Try using caps
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

2nd thing, MASQUERADE needs to be allowed in your kernel.

3rd thing, don't MASQUERADE on a nic with a static address. Better to -j SNAT --to-source xxx.xxx.xxx.xxx
MASQUERADE takes a whole heap of CPU time locating your ip address for each connection. It was designed for dynamic numbers.

Regards,
Peter.

4th thing module for iptables must surely be loaded (modprobe)
5th thing goto www.linuxguruz.org/iptables -for firewall examples
6th thing in iptables you need minimum of three entries for sharing
..check this example
echo "1" > /proc/sys/net/ipv4/ip_forward
iptables -P FORWARD DROP
iptables -A FORWARD -s $localnet/24 -j ACCEPT
iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -t nat -A POSTROUTING -s $localnet/24 -j SNAT --to $ipofIneteth

(localnet=192.168.1.0 -for example)
ipofIneteth=123.123.123.123 -your external ip
if you have dhcp use last line like this
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE (if eth0 is your outgoing device)