Computer A (Internal Win2k)-------: IP: 10.0.0.1
Computer B (Linux Box)------------: IP: 184.108.40.206
Computer C (General Internet pc)--: IP: 220.127.116.11
Computer B has 1 network card. It is on the same LAN as Computer A and has external Internet Access.
Computer B can access both Computer A and Computer C.
There is a Webserver on Computer A -> 10.0.0.1:80
Computer C (general internet) cannot access the above Webserver on Computer A.
We want to use Computer B to forward all traffic from Computer C to Computer A.
iptables firewall can be used to forward such connections.
Going from Scratch:
iptables -F # Flush rules from iptables
iptables -t nat -F # Flush rules from nat table in iptables
iptables -t nat -A PREROUTING -p tcp -d 18.104.22.168 --dport 80 -j DNAT --to 10.0.0.1:80 iptables -t nat -A POSTROUTING -d 10.0.0.1 -j MASQUERADE
If Computer C types http://22.214.171.124 into their Internet, they will see the Webserver on Computer A (10.0.0.1).
This Works. Will get around to perhaps explaining it later.
Look at the complete Iptables_Firewall