Branch office DNS issues?

[Booty]

We have a relatively small network here - 3 offices. Our main office has all servers - 1 domain controller, 1 webserver, 1 application server at this point - and about 20 workstations. The branch offices each have about 5 workstations, and have a VPN link back to the main office.

We recently upgraded/replaced our application server, and now the branch offices are having trouble with our database application not being able to connect to the new server - they get an error message when they attempt to login.

I'll connect to them via VNC to witness the issue - I can usually ping the IP address of the server from their machines, but have issues pinging it by name. I also can't browse it's shares using \\computer - but it's fine using \\192.x.x.x - so, though I know very little about how DNS works, I'm pretty certain that's the issue.

The weird thing is that it only happens on some of the computers (about half), and only some of the time - usually first thing in the morning. After playing around with it for a while, they eventually work, but I don't think there's something specific I'm doing to trigger it... it's like it just eventually starts resolving the name properly.

It's pretty frustrating, so I'd like to figure out what the deal is. Any suggestions on where to start? I already ordered a book on DNS and BIND so that I can learn what the hell I'm talking about, but in the meantime I just need to get it fixed asap.

 

[randal]

Is the new app server part of the domain? Also, does it have any shares open / listed in the directory? I had some trouble very similar to what you're seeing - for some reason a server wasn't advertising itself at all - I opened up a share and the problem went away. Can you see the server's name in `net view`? Also, check your DNS snap-in and see if the app server's name appears under the zone for the domain. Also, check the microsoft knowledge base as they have some great articles on how AD & DNS work together.

 

[err]

first thing's first... do you have a domain controller runnning dns servers?
If yes, go to your app server and make sure its properly joined to the domain. You can also force dns registration by issuing command:
ipconfig /registerdns

Then, check your DC dns server and make sure that the entry is properly created (could take up to 15 minutes)

by the way when you upgraded your application server, did you use disk imaging software such as ghost? If yes, I would highly suggest unjoining / rejoining the domain. Run ghstwalk as well to change the SID.

 

[Booty]

Nope, didn't use ghost - I shouldn't really say 'upgraded' - it was a brand new server, and a new version of the application was installed - only the database was moved from one server to the other and upgraded.

At this point, it looks like it's an issue with the new version of the application. I went through your suggestions, read up on DNS, and checked out all the basics - everything seemed fine. I met with the software company down in Atlanta last week and talk to a rep from another company - they were having the same issues with their branch offices, as was another company.

So thanks for all the replies and advice - now let's see if our vendor can fix the issue.