Re: Port forwarding question

[Mr Ritter <netfilter@candlefire.org>]

Greetings,

Dimitri Yioulos wrote:
> Noob, question:
> 
> I want to allow a vendor to access a piece of equipment on our LAN  
> (192.168.100.46) through port 4000 from outside via a server in our 
> DMZ (www.xxx.yyy.zzz).  While I should know how to do this, I'm not 
> 100% sure.  Can someone help?

DNAT.

for example:
iptables -t nat -A PREROUTING -d www.xxx.yyy.zzz -i eth1 -p tcp --dport 
4000 -j
DNAT --to 192.168.100.46
iptables -t filter -A INETIN -d 192.168.100.46 -p tcp --dport 4000 -j ACCEPT


> Oh, and separately, how would I allow that access only through the 
> vendor's ip address, if that were the way I decided to go?

for example:
iptables -t nat -A PREROUTING -s 1.2.3.4 -d www.xxx.yyy.zzz -i eth1 -p 
tcp --dport 4000 -j DNAT --to 192.168.100.46


Regards,

--
Ritter