DNS set up questions

I really need a hand, and I am hoping someone can help me out. Let me tell you what I see:

Our DNS seems to be pointing to a 10.90.x.x subnet. Everything that has a 10.90 IP does not notice any issues.

However, the other locations, which are on a 10.93, 10.91, 10.95 and 10.96 subnets all see a LOT of slowness, and 10.91 in particular is seeing epic slowness and 30 megs of a 50 meg pipe being used. Any ideas of what I need to do to change that? The 10.91 site has two domain controllers and they both have the DNS role, which I am thinking is not correct, what do you guys think?

It is a mixture of Server 2003 and 2008. Only one site in active directory, but I did try to break them out in to different sites this past summer, but when the problems started I reversed that. The subnets I created in sites still show, could that be it? Or do you guys think I am dealing with a dying/dead switch?

 

I'm surprized no-one has taken a poke at this yet.

I only have a little experience with Windows Server 2008, with it's dual network connection and virtual networks inside, but Server 2003 is simple enough to me.

One DNS server is good for a network segment. The Server 2003 Network connetor card is the address to use as a Primary DNS. I don't think having two causes any difficulty, they each will update eachother's records.

As for all the subnets; if all your hardware fits onto one segment, (less than 255 machines), and you have returned to a single network, then the Subnets should all match.

If the 10.90.x.x is what is working, and the servers network connection is on that (Subnet?), or is that a public IP address?

It's very important to keep a log of when and how changes are made, then you can go back and undo things or redo them. Make a note of the current subnet settings, and then change them to the same as the 2003 servers subnet. If the traffic flow dosn't improve, that's not the issue, and you can change it back.

Something to try anyways. I'm still new, so be shure to keep a record of changes if you try this.

Cheers.

 

Thank you, I will give it a shot!