Hi,
 
I've been trying to forward port 21 to an ftp server on another machine, IP address  10.0.0.199.
 
eth1 - external (connected to the net)
eth0 - internal
 
/sbin/iptables -A FORWARD -p tcp -i eth1 --dport 21 -j ACCEPT
/sbin/iptables -A PREROUTING -t nat -p tcp -i eth1 --dport 21 -j DNAT --to 10.0.0.199:21
 
but can't get it to work..
 
any ideas ?