Проброс портов

$EXTERNAL_IP = 10.0.0.0
$INTERNAL_IP = 192.168.1.1

iptables -I FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT

iptables -A FORWARD -d $EXTERNAL_IP -p tcp --dport 8080 -j ACCEPT

iptables -t nat -I PREROUTING -d $EXTERNAL_IP -p tcp \
    --dport 80 -j DNAT --to-destination $INTERNAL_IP:8080