No response from IIS if my IP is local

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QUESTION :

The problem is simple: If I set the webserver’s IP address as my desktop’s default gateway in TCP/IP settings, I cannot open any locally hosted site at our webserver on my PC. I can open any other site from the internet as well. If I use a real IP address then I can open our sites too.

The previous webserver was Windows Server 2003 Webserver Edition, and it had no problem like this. The newer one is Windows Server 2008 R2 Standart Edition.

All clues are now listed. If you need any info or got idea, I’ll supply more on request.

Addition & correction a bit:

I cannot open any site if my IP is local. ie:
webserver 192.168.35.211
mydesktop 192.168.35.45

  • I can telnet mysite.com 80 but there are no responses to my requests.
  • I can telnet mysite.com 25 and there is response.
  • VPN connection from home to Webserver makes the sites “offline” to me. I can still open supersuser.com thru Webserver

So I think there is IIS related problem instead of network.

ANSWER :

What I think is happening is this. Please correct me if I am wrong.

mysite.com has public ip address

mysite.com get translated to internal IP address by your firewall to an internal RFC1918 address(192.168.35.211)

When you are on your local network you can access 192.168.35.211, but not mysite.com?

This is normal behavior as the firewall or device performing the Address translation cannot hairpin the traffic through it, so your packet go out, but they never come back in.

A normal way around this is to either use split horizon dns zone. IE inside mysite.com resolves to 192.168.35.211, outside it resolves to your public ip. Or you use the internal name (http://mysite.local/ or the like..)

The same thing happens on VPN, since you cannot access the public resources, since the default gateway is probably set on the vpn connection. Changing that is either up to your network admin (or if you have control, you can uncheck use default GW on remote network, and manually set routes to your office network).

But if my above assumptions are correct, your problem is network related and not IIS related.

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