Filter | My Site

drop/reject are not allowed in nat, so, forward to other port if source matches.

iptables -t nat -I PREROUTING -i {SOME_INTERFACE} -p tcp --destination-port {INPUT_PORT} -j REDIRECT --to-ports {NEW_PORT}

1	iptables -t nat -I PREROUTING -i {SOME_INTERFACE} -p tcp --destination-port {INPUT_PORT} -j REDIRECT --to-ports {NEW_PORT}

iptables disallow nat by source by My Site: https://sskaje.me/2016/08/iptables-disallow-nat-source/