Nice try but no luck $IPTABLES -t nat -A POSTROUTING -o $INTIF -i $INTIF -j
can't use -i in POSTROUTING So I tried $IPTABLES -t nat -A POSTROUTING -o $INTIF 192.168.0.0/24 -j MASQUERADE No luck there although this time the rule is correct. So I tried $IPTABLES -t nat -A POSTROUTING -o $INTIF 192.168.0.3 -j MASQUERADE ...but no success. I know this is a silly problem, since I could used the internal IP of the web server, but I want to crack this to be sure the server can be reached via the external address. At the moment I confirm this using a web anonymiser. Mark ----- Original Message ----- From: "Antony Stone" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, July 10, 2002 4:22 PM Subject: Re: Destination NAT Onto the Same Network Problem > On Wednesday 10 July 2002 2:54 pm, Mark Ayad wrote: > > > I have a problem with the following Firewall Script which works fine apart > > from when I try to INTERNALLY connect to the webserver 192.168.0.3:80 > > using the public IP which if I'm right should be the same as $EXTIF. The > > internal machine I'm launching the request from is actually the webserver > > (but that shouldn't matter). > > > > I know I'm missing a line from what I read in > > http://netfilter.samba.org/unreliable-guides/NAT-HOWTO/NAT-HOWTO.linuxdoc-1 > >0 .html and I've tried nearly every combination I can think of except the > > one that works that is. > > > > So whats the missing line ? > > > > $IPTABLES -A INPUT -p tcp --syn --destination-port 80 -j ACCEPT > > $IPTABLES -A INPUT -p tcp --syn -j DROP > > > > $IPTABLES -A FORWARD -i $EXTIF -o $INTIF -j ACCEPT > > $IPTABLES -A FORWARD -i $INTIF -o $EXTIF -j ACCEPT > > $IPTABLES -A FORWARD -j LOG > > > > $IPTABLES -t nat -A PREROUTING -p tcp -i eth0 --dport 80 -j > > DNAT --to-destination 192.168.0.3:80 > > > > $IPTABLES -t nat -A POSTROUTING -o $EXTIF -j MASQUERADE > > This one looks a bit odd to me, even though I've written it myself, but I > think it should do the trick: > > $IPTABLES -t nat -A POSTROUTING -o $INTIF -i $INTIF -j MASQUERADE > > If it doesn't, then just use the standard version: > > $IPTABLES -t nat -A POSTROUTING -o $INTIF -s a.b.c.d/n -j MASQUERADE > > where a.b.c.d/n is your internal network range. > > > > Antony. > >
