I got some problem in wireless AP Setting

I have a Buffalo WHR-G54S wireless ap and set to 192.168.1.1 (NAT).
Web Server has an IP 192.168.1.2 and it is in DMZ.
Client computer A has an IP 192.168.1.3

Now, I can access the web server from client Computer X
through the WAN side ip (the ip that my ISP gave me).
and I also can access the web server from Computer A
with an internal ip 192.168.1.2

However, I cannot access the web server from Computer A with the real ip.

please give me some hints of what and how to set my ap so that I
can use the client computer A to access the web server without
typing in 192.168.1.2 because I want to use FQDN to access it. Thanks.

There may be multiple points in your problem:
1) Are you using a so-called dynamic DNS service? Is your domain name "yourwebserver.com"?
2) When you say you want to access your web server with FQDN, do you mean you are trying to access the server like "www.yourwebserver.com"?

If yes, does your DDNS service support wildcard first of all?



What do you mean by "real ip"?
Are you trying to access the web server from Computer A, which is inside your LAN?

What do you see when you try to access your web server from Computer A?
Isn't it the web setup screen.
Many routers, including Buffalo's do not allow you to access a LAN server from another LAN client using global IP.

I think this is the reason....
thank you..