On our network, we use DHCP. DHCP is given out by our Sonicwall NSA 240 device.
We have a domain network, with our own DNS server, etc..
I don't know why, but on my network, the workstations are picking up a different DNS other than the one our Sonicwall is giving out. Which is causing havoc. Active Directory no longer works correctly, If my DC is offline, nobody can go on the internet, etc...
The DNS IP that its picking up is of this ADP server. I called their tech support and they weren't very helpful. They said the DHCP on the machine is turned off.. No scopes defined, etc.. I have no control over how this server operates, so I think I am SOL.. They added my DNS as a forwarder to their machine, but it still causes problems if the ADP server is doing maintenance.
Its weird because it doesn't happen all the time, when you do an ipconfig /renew, the workstations will get the correct DNS from the sonicwall. Its when it does an auto-renew or something that it will pick up the DNS IP from the ADP server.
I guess an option would be to move this server to an entire different subnet..
Is there some workaround from a network perspective? Is there something I can do to my switch to fix this issue? My switches are Cisco.