What has gone wrong with local network name resolution?

Question

I am using Windows XP Service Pack 3. I set up a Firebird SQL server on a machine on my 5 computer local area network. I used to be able to access it by using the server name "Server-win7". Now, I need to use its IP address. I can access the database fine using the IP address of the machine, but this is not really a good solution. The IP addresses are not as intuitive as names and they are also dynamic unless I set them all up as static.

I don't know why the name/IP resolution no longer works. I have done nslookup and it tells me that my DNS server is outside my local network on a Verizon server somewhere and it provides the wrong address for my database server. I have used the Microsoft Network Monitor and I see that my requests to my server do get routed to that incorrect server that is not even on my LAN. It seems odd to me that Windows Explorer can still browse the network by computer name but other software cannot.

Do you have any idea why the local name resolution stopped working? How can I restore peace and harmony here on my LAN?

Thank you for your help.

Answer 1

Windows Explorer is using NBT (NetBIOS over TCP) to resolve the name, while it sounds like your software is using DNS to resolve the name. NetBIOS works very differently than DNS; in a nutshell it's searching locally rather than asking a server (that's somewhat inaccurate, but basically the point.)

As for fixing the problem, you could either set up a DNS server locally (maybe even use your router) or add Server-win7 to the hosts file on each PC. Given that there is a valid response to the DNS request (which seems odd) you'll have a hard time getting the name to resolve to your local PC. You could try running ipconfig /flushdns though.