The "DNS auto-detect and configure" feature turns on after Connector is installed on clients. This feature tries to find the server that is running Windows Server 2012 Essentials, and then uses the server’s address as the client's DNS address. This may cause the Internet connection to be temporarily disconnected in some network environments.
Update Rollup 3 introduces some new solutions to skip DNS auto-detect and configuration on the clients.
If you already know about the longstanding issue with DNS on client machines that are connected to your Windows Server 2012 Essentials, and have recently found your client connectors got updated with UR3 (Update Rollup 3), then this article (with video) is for you! If you have to reboot or take down your Window Server 2012 Essentials system, your remote systems will be stuck, with no way to surf the web. That's not good. This article is all about breaking that dependency, giving back your independency!
Every time a rollup comes along, I have a systems to clean up, many of them not in my home. It's getting a bit old, this patching things up temporarily on all client systems by doing the usual stopping of a service, then setting back to "Obtain DNS server address automatically" which I explained here. This time, there's a more elegant and more permanent way to handle this. It's not perfect, but it's a step in the right direction. For me, well, I'm really just frankly buying myself some time, before I rebuild with Windows Server 2012 R2 Essentials.
UR3 is seen as KB283201 in the Windows Update History on your WS2012E system, pictured below.
This first fix will prevent you from having to fiddle with any future systems you install the client connector on, so they won't have their DNS changed from DHCP to the IP of your WS2012E server.
You can also change the behavior of all clients that are managed by a Windows Server Essentials server. To do this, set a DWORD-type registry value named SkipAutoDnsConfig in the following path:
- HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Server\Networking\ClientDns
Then, set the registry value to 1.
- *Note** After this solution is applied, all clients that are connected to the Windows Server 2012 Essentials server skip the DNS configure feature. The existing clients that were connected to the Windows Server 2012 Essentials server before this change must reinstall the Connector and then reconnect to the Windows Server 2012 Essentials server.
After Update Rollup 3 is installed, all the clients that are joined to the Windows Server Essentials server automatically skip the DNS detection. The existing clients that were connected to the Windows Server Essentials server before the update rollup was installed must reconnect to the Windows Server 2012 Essentials server.
This second fix will prevent the connected client machines from having their DNS settings messed with in the future, by that "Windows Server LAN Configuration" service I discovered and blogged about, way back in Sep 2012 here.
To skip the automatic DNS detection on a client that is managed by Windows Server Essentials, add a String-type registry value named SkipAutoDNSServerDetection in the following path:
Then, set the registry value to true.
This registry change takes effect immediately, no reboot or logoff/logon required, and you can also close regedit now.
Finally, don't forget to restart the "Windows Server LAN Configuration" service by launching services.msc, right-clicking on the service, and choosing "Restart".
Change the TCP/IPv4 settings of all your network adapters, including Hamachi, VMware, and NICs not in current active use, making sure they're all showing "Obtain DNS server address automatically" turned back on, with step-by-step set of clear screenshots in the explanation. No reboot needed, changes take effect immediately.
If a video walkthrough of the process of cleaning up the client PC sounds good to you, check out the video below, where I walk you through each and every step, on a Yoga 13 running Windows 8.1.
Update Rollup 3 for Windows Server 2012 Essentials Article ID: 2862551 Microsoft Support
Windows Server 2012 Essentials remote client loses its Internet connection, here's your DNS-related fix by Paul Braren on TinkerTry.com, Sep 09 2012.
Windows Server 2012 Essentials UR3 coming soon, with the DNS fix I requested?
by Paul Braren on TinkerTry.com, Aug 24 2013.
Remote WS2012E client PCs (that skipped domain join during install) can't surf after Update Rollup 3, here's the fix
by Paul Braren on Home Server Show forums, Nov 04 2013.