Trying to use IPTABLES on my linux machine which acts both as my gateway/router and as my firewall. I have a win2k box behind this on a private IP(10.0.0.3 for this examples sake). My linux box would then be 10.0.0.1. I have tried this:

iptables -t nat -A PREROUTING -p tcp --dport 3000 -j DNAT --to 10.0.0.3:3000

My win2k box is running G6FTP on port 3000, hence the forward. However when I try to ftp into port 3000 on my linux machine I immediately get a connection denied. The packet did NOT traverse my other tables(because it was not logged which is the last step before being dropped) so I have NO clue how to debug this, any ideas?

J

for those that care, this fixed it:

iptables -t nat -A PREROUTING -s ! 10.10.0.3 -p tcp --dport 3000 -j DNAT --to 10.10.0.3:3000

I'm guessing that the packet replies from 10.10.0.3 were being redirected back to itself making a lovely indefinate loop.

J