We have a bunch of 2008-2012 HyperV hosts who have Windows Server domain controllers (2008 DC level, 2008 and 2012 servers across different unrelated sites). Occasionally, when the DC guest comes up after a host reboot after updates, clients call us the site doesn't have internet (Intranet works, external does not). In the DNS manager, I click Properties of the DNS server (the DC), click Monitoring, and run Simple and Recursive query test. Simple always passes, recursive always fails. We restart the DNS Server service and then everything passes.
The servers are configured to use the ISP DNS (ie. 75.75.75.75, 76.76.76.76) as forwarders.
The issue is, we're an MSP. We should know the site doesn't have internet before they do. We should be able to call them and say what is happening before they call us. We're using Kaseya and have the ability to set up monitoring sets and what not, so that's the tool we have to use. DNS is one of those things I don't touch too often so my knowledge may be a bit rusty.
My ideas have been checking the perf monitor (DNS sets) for failures while DNS Server is turned OFF, which did not give me meaningful results. I've been trying to figure out where the results for "Perform Automatic testing at the following interval" is located since I could just check that for failures, but I have no idea where it is. Another idea is to do 'nslookup 127.0.0.1 ' which results in a failure, but I don't know if that will help me.
I am looking for something a bit more in depth than clearing cache and pinging a website. Something more robust I can deploy to 50 sites. Any ideas?