We recently decided to move our IP address on one of our Windows Server 2008 R2 x64 Enterprise servers to a new NIC. I first removed the static IP on the existing NIC, disabled it, and reassigned that same static IP to the new NIC. Everything seemed to be working fine and clients were still able to connect to the server.
This morning we noticed that we could no longer resolve the DNS name to the IP of the server.
I manually created a DNS entry and everything was fine - about an hour later the same issue occured and the DNS entry was gone again (making the server inaccesible to our clients using DNS).
I also logged into the server and ran ipconfig /registerdns hoping that it would create a new DNS record for the server. This worked OK again for another hour or so.
I finally just restarted the server and am still experiencing the same issues with the DNS entry being removed after about an hour. I have checked the scavaging settings as well as the "Delet this record when it becomes stale" Entry - I made sure it was "unchecked".
What else could be happening that would cause this issue?