echo 1 > /proc/sys/net/ipv4/ip_forward

iptables -F FORWARD
iptables -t nat -F POSTROUTING 

iptables -A FORWARD -i world -o LAN -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A FORWARD -i LAN -o WORLD -j ACCEPT
iptables -A FORWARD -j LOG

iptables -t nat -A POSTROUTING -o world -j MASQUERADE

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iptables -A PREROUTING -t nat -p tcp -d 128.61.105.190 --dport 22222 \
          -j DNAT --to 10.1.1.7:22