Hello everyone,
I have a weird problem that I want to share, so that someone more expert can tell me why this problem occurs.
I have a small home network, with a gateway/router/adsl modem connected to the internet (USRobotics 9106). Two pcs are connected to this device..
The gateway's IP is 192.168.1.1 while the pcs are 192.168.1.11 and
192.168.1.12. No DHCP. The pcs are configured with their fixed ips and the gateway/DSN server set to 192.168.1.1. Everything works fine, both the pcs can access the internet for surfing and email receiving.On one of these two pcs I have installed a webserver, that I have set up to listen to port 81. In the gateway's virutal servers configuration, I have set the TCP incoming traffic on port 81 for the pc with the webserver.
The webserver works fine when someone else surfs on it using my WAN external ip address (I've tried it with friends, with http://xxx.xxx.xxx.xxx:81)PROBLEM : I can surf on it from my network only if I use the LAN ip of the webserver (http://192.168.1.12:81) and NOT the external WAN ip.
If I try using the wan external ip address, I cannot reach the web server. It's strange because if I try accessing the server via a free proxy
It has probably something to do with the gateway, because I have tried to access the internet with an old traditional plain modem without router, and when I use that, the webserver is reachable also using the external wan ip address.
How can this be ? I hope you didn't fall asleep while reading this message :-)
Thank you for your help Mirko