Q & A: NAT or modem router

Question:
Hello, I am having a slight problem with EHCP.

Guest: I entered all of the correct information to set it up such as the external internet protocol address, mysql password, etc. The only problem I am having is viewing it from my external ip. I can view from localhost or from my router assigned ip, but I cannot view it from my external ip?
Also, what is weird is that this is a fresh ubuntu installation.
I have tried reinstalling ubuntu several times and reinstall ehcp. I think it might be my router. Even though i forwarded my ports, i think there are some other settings i might have to change.

Guest: Does mac cloning interfere with the control panel?

Answer:
Hi,

Did you set up NAT on your modem/router ?
if you didn't, then you should do it.

In order outside world to see your server, you need to setup NAT on router, if you are behind a router. (This is not true when your server has a direct connected real ip)

described basicly in http://www.ehcp.net/?q=node/355#comment-399