Clients forgetting DNS Server settings - even though supplies through DHCP

[TheFopp]

Have a strange issue on a couple of PCs in our setup. They seem to be forgetting the addresses of our DNS Servers every so often.

The DNS Servers are set through DHCP, and the PCs pick up an IP address and the Gateway address fine, but sometimes don't pick up the DNS Server addresses (which seems odd as all this is pushed out through the DHCP).

It can be repaired in network connections by just clicking repair, but even then, once repaired, they every so often lose the DNS server settings changing from the 10.0.1.100 & 10.0.1.101 settings given out by the DHCP to a pair of addresses in the 192.169 range.

Does anyone have any thoughts on whats happening. Nothing seems to be appearing about this in their Event Viewers.

[SimpleSi]

When I've a rogue machine nowadays, I just stick a new net card into it and problem goes.

I've spent too much time in the past trying to fault find what the hecks happening.

And then you end up putting a new net card in

regards

Simon

PS but just check your subnet mask setting just in case

[TheFopp]

Will do that and see if it helps.

[rvdmast]

it could be that your DNS server is set through GPO (or directly in the registry) which will override settings assigned through DHCP.
see New group policies for DNS in Windows Server 2003

...Group policy always supersedes the local configuration as well as the DHCP configuration....

[Michael]

If your machines are getting a 169.x.x.x this would point to a DHCP issue.

If you open up DHCP, right click Scope > Display Statistics are you running low on addresses?

Now right click Scope > Properties > DNS, make sure the following are ticked/selected:
- Enable DNS dynamic updates according to settings below
- Dynamically update DNS A and PTR records only if requested by the DHCP clients
- Discard A and PTR records when lease is deleted

Navigate to Scope Options and make sure Router, DNS Servers and DNS Domain Name are populated. Under DNS Servers, make sure your school server is first in the list.

If all this is correct, then right click your servername.domain in DHCP, All Tasks > Stop and then the same to Start DHCP.