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Hi. I have a Server 2012 R2 that is in our office. It’s a DC Server but the primary one is at our head office. Last night, Server updates were done - nothing critical, just some security updates and the Server was rebooted. Since then, it’s not worked correctly. I’ve had a look through the settings and it appears that the DNS has disappeared. When I open DNS, it’s prompting for a Server to connect with and even if I cancel it shows the DNS Window and talks about going to Action and adding a new Server

I’ve tried reading up online about restoring the DNS but all these articles I’ve come across talk about running a DNS backup first then restoring. I have looked at the DNS Folder in System32 folder but I can’t see any specific backup configurations for it.

Is there a way I can restore the DNS?

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DNS if you configure it properly is replicated to all domain controllers (either in the domain or forest depending on how you set it). As long as the zones are AD integrated, you should be able to add the DNS role back to the server and it should populate again. Check your zones on the head office server and make sure they are AD integrated zones.

Worst case scenario you could always demote and promote the domain controller.

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Hi Patrick

I’ve opened the DNS on my other DC Server and gone to the Forward lookup zones and checked the properties. It says Status is running and type is Active Directory Intergrated and replication is all DNS servers in this domain. I’ve looked at the primary DC and it also says the same. So how do I go about getting it all to go back into place? I had a DNS error in my DNS Server event logs and I was getting 4000 and 4007 errors. When I try and add a server I get access denied: do you want to add one anyway. I found this article in my googling attempts =

Should I follow those steps?

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I would, yes. And when all else fails, you can just demote the faulty domain controller and promote it again.

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Hi Partick. I followed the steps in that article but I’m getting this error:

The machine account password for the local machine could not be reset
The network path was not found
The command failed to complete successfully

Is there another way I can get the DNS Zones from the PDC to update to this Server other than running a demotion and promotion?

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Hi All. In the event logs I’ve found this message for the Netlogon warning event

Fix possible misconfiguration(s) specified above and initiate registration or deletion of the DNS records by running ‘nltest.exe /dsregdns’ from the command prompt on the domain controller or by restarting Net Logon service on the domain controller.

I’m just checking if I run the nltest command on the Server having issues, if that command is designed to pull the DNS details from the other DC Server and that might fix my issue?

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Before you worry about replication, fix the service first if you can’t even manage it locally on the affected machine. Have you checked in services.msc is the DNS server service even running?

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Hi Dennis. Yes I can confirm the DNS Server Service is running. I’ve tried restarting that, and restarting the netlogon service as well, setting the preferred DNS to my main DC with this Server as the alternate and restarting the service and it still won’t trigger a replication

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How many DCs you you have in total and how many DCs per site ?

Are they full DCs and/or RODCs ??

The easiest config is to see the DNS server settings on the IP address config of ALL the DCs

  • If there are 2 DCs in HQ, DC-HQ1 would have DC-HQ2 IP address as primary DNS server & 127.0.0.1 as secondary DNS server, DC-HQ2 would have DC-HQ1 IP address as primary DNS server & 127.0.0.1 as secondary DNS server.

  • Then the other site should have 2 DCs as well… DC-site1 would have DC-site2 IP address as primary DNS server & DC-HQ1 IP address as secondary DNS server with 127.0.0.1 as 3rd DNS server, DC-site2 would have DC-site1 IP address as primary DNS server & DC-HQ1 IP address as secondary DNS server with 127.0.0.1 as 3rd DNS server.

Then all the DCs are supposed to be listed in their respective sites in Domain Sites & services.

If the above have been changed, then run “ipconfig /registerDNS” on ALL the DCs and wait for 24-72 hours for replication to take place or complete, check event logs for errors.

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