The forward rules on the gateway are:
# "Accept forward all connections to port 3306 on ppp0"
iptables -A FORWARD -p tcp -i ppp0 --dport 3306 -o eth0 -j ACCEPT
# "All stablished connections are ok"
iptables -A FORWARD -i ppp0 -o eth0 -m state --state ESTABLISHED,RELATED -j ACCEPT
# "All connection from inside to outside are accepted"
iptables -A FORWARD -i eth0 -o ppp0 -j ACCEPT
# "Rest go away"
iptables -A FORWARD -j REJECT
NAT rule:
iptables -t nat -A PREROUTING -p tcp -i ppp0 --dport 3306 -j DNAT --to 192.168.0.80 -s 200.10.10.1
Are you using MASQUERADE or SNAT ? If you aren't then the outside can't 'see' your internal server.
Jeff
