iptables -t nat -A PREROUTING -p tcp -m multiport --dports 80,443,2068,8192 -j DNAT --to-destination 192.168.1.175
Just adjust the "--dports" to the ports you need and the --to-destination to the destination IP (note it must be on the same network as the server running iptables
#enable web server connection
iptables -t nat -A PREROUTING -p tcp -m tcp --dport 4142 -j DNAT --to-destination 192.168.1.252:80
iptables -A FORWARD -p tcp -d 192.168.1.252 --dport 80 -j ACCEPT
In the case above, when a user hits the IP of the machine on port 4142 it forwards to 192.168.1.252 port 80 is what the PREROUTING does for us. However, for forwarding to work and actually hit there, we need to add the destination IP and port as a FORWARD as you can see on the second line.
Of course you can change port 4142 to whatever open port you like.
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