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sudo ufw allow 25565/tcp &&  sudo sysctl -w net.ipv4.ip_forward=1 && sudo iptables -t nat -A PREROUTING -p tcp --dport 25565 -j DNAT --to-destination 40.40.40.2:25565 && sudo iptables -t nat -A POSTROUTING -p tcp -d 40.40.40.2 --dport 25565 -j MASQUERADE