Constant Packets being received only in XP

[donnach]

We have installed around 400 new Dell Optiplex with XP in our labs and classrooms in December. Ever since, the network has slowed noticeably. I have run packet queries and the leading was Netbios. We also run some Altirus software with a Host file script pointer. Our servers are W2k for logins and Unix for the data process, one novell groupwise (that the student boxes do not access).
The faculty and staff boxes are similar, without the extra softwares. All have SP1, Officexp with all patches.
The problem is all seem to have a packet received stream that I can not find a source for or a way to stop. The avarage is 2k packets per sec. With over 1000 boxes, mostly on XP, this really hinders the network. My 2k and 9x boxes do not have the same problem.
I've disabled the Netbios, QOS, and pointed the DNS to one of my servers (and tried to the outside DNSs). Maybe I should unplug the switches and run myself a direct line and get maximum bandwidth.....
Thanks for any feedback or direction to try.

 

[danUK]

When you say - {and pointed the DNS to one of my servers (and tried to the outside DNSs)}.
Which of your servers are you running as a DNS server?
Do you have a properly configured reverse lookup zone on your DNS server?
Are your machines picking up addresses from DHCP?

Can't think why your XP machines would be affected and your W2K not?

 

[donnach]

I'm using a Novell box for local DNS. Using Static addressing and have the reverse tables built.
And I too am confused why not w2k units vs xp. On my test bed I have isolated (if you call it isolating) to IP and UDP packets only. I'll be looking at the auto updating items this afternoon, but i have 300 units that don't have autoupdates on them doing the same. I plan on doing a packet port sniff to try the UDP side.
Thanks for the reply.

 

[bcastner]

XP differs from previous versions of windows in that it uses DNS as it's primary name resolution method for finding domain controllers: How Domain Controllers Are Located in Windows XP

http://support.microsoft.com/default.aspx?scid=kb;en-us;314861

If DNS is misconfigured, XP will generate of lot of traffic attempting DNS resolution using legacy NT4 style NetBIOS.

See this thread for a possible solution, it deals with other consequences of DNS misconfigurations, but the solution should apply in this case as well
thread779-540080