|It sounds to me like you have configured something incorrectly. Check the DNS IP address as you've configured it in the DHCP service. It should be the IP of the DC with the DNS service on it. Also, check to ensure your DC's DNS IP points at itself.|
I hope you're not letting a server get it's IP from DHCP!?!?
Any/all services should have static IP assignments so their IP never changes. So servers, network printers, etc, are always statically assigned IP's that are outside of the DHCP scope (so as to avoid possible duplicate IP issues).