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We have a Windows SBS 2008 machine. Several ports need to be forwarded from the router to the server (the machine hosts a FTP server, a Web server, and we need to be access it through Remote Desktop).

We recently changed routers (from SpeedTouch to Huawei EchoLife HG520s). With the previous router, port forwarding worked fine. Now, after setting up port forwarding on the new router, nothing works anymore. Can anybody help me with directions on how to diagnose/troubleshoot port forwarding problems on the router and in Windows SBS 2008? E.G.: after forwarding a port in the router interface to the internal IP of the server, how can I see in the SBS 2008 logs if the request is properly forwarded to it?

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This is almost certainly a problem with the router, as long as the SBS 2008 IP is configured properly. Can the SBS2008 box browse the internet? –  tomjedrz Jun 9 '10 at 14:50
    
Yes, this was the problem. The new router had a differnt default internal IP, so nothing worked until I changed the gateway and DNS on the server. –  Alt_Doru Jun 10 '10 at 11:27

3 Answers 3

As long as you have a static IP on the server and not DHCP'd through your router...if it's a home router as some have suggested...it should work as long as you have the proper port going to your server's services.

  • Verify from within the network that you can connect to the services.
  • Verify that you have the correct external address (www.whatismyip.com).
  • Verify that the ports are "open" and not firewalled on the server.
  • Verify that the ports are "open" from the outside (nmap is your friend, otherwise you need another service to scan your external IP)
  • Restart the router to verify that the new settings "took". Shouldn't need to be done, but if it's an inexpensive router, you never know.
  • If you have any logging available for particular services, check the logs to see if there's any connection attempts or anything showing up on the server side.

You might want to consider with those services (FTP especially) just putting the server in a DMZ. You're really kind of opening it to all sorts of hack attempts with the services you mentioned all on one machine and I personally wouldn't want it on the same subnet as my personal machines. DMZ it and you might have an easier time than individual port forwarding.

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Use Telnet to connect to your external IP and the port you forwarded. If it connects it is working :)

If its not give us some screenshots of your port forwarding page on the router config.

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Take a look at WireShark http://www.wireshark.org/

This will let you monitor the network traffic on the SBS side of things.

As Campo suggested, running telnet against the various ports.

However, RDP doesn't respond as well to telnet as services such as SMTP, POP, etc. You will get a connection, but no output to the screen, so you have to take note of the difference between that and a timeout for checking RDP via telnet.

With WireShark running you can make the telnet attempts to get a better view of what is going on at the server.

Not familiar with your router, so can't say much there. It looks like it is a standard home network router though, so probably not a lot of diagnostic options there.

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