I have a strange behavior on one of my windows2003/IIS6 servers.
I have two network cards on it, let's call card A the card which connects the server with the internet, and let's call card B the card which connects the server with the intranet. The server is used by many users who connect to IIS with their netbooks.
The problem is that from time to time, the card A stops working.
I can reach the server in RDP through the card B, and I see that A is enabled but without any traffic. I can reset it, disable and re-enable it, but with no luck. The only thing that I can do is reboot the server, which is annoying. Nothing useful in the system logs.
Only once I've been able to reproduce this behavior, when calling a very simple aspx page which only streamed a file (using Response.WriteFile), and calling the page from a netbook. reinstalled windows on that netbook, and it started downloading the file without locking the server card.
I am out of answers, any help greatly appreciated.
Thanks.
Check your default gateways on the cards. Make sure that only card A has a gateway.
Also, if you haven't tried performing an issreset you should perhaps do that first before disabling an enabling the card, then if that doesn't fix it, after the card. If doing it first fixes it, you could be looking at an IIS problem.
I think there is a very good possibility that you have a firewall or some other external device that is causing this behavior and not the server itself. This sounds like an attack script or rate limiting type behavior of a firewall protecting your server.
Do you have other devices in the same subnet as the 'A' card? If so, try connecting from that device to your 'A' card and see if it is successful.