DCOM was unable to communicate with the computer 8.8.8.8 using any of the configured protocols; requested by PID 1830 (C:\Windows\system32\dcdiag.exe).
This error and a couple of others to different IP addresses but referencing the same PID come up about once an hour. We are stumped as to why. No other domain controller is showing these errors.
I do see these IP addresses in HKLM\SYSTEM\CurrentControlSet\Services\DNS\Parameters, but I see them too in our other two domain controllers which aren't tossing this error.
Suggestions?
Best Answer
It sounds like Wwindows is assuming your DNS Forwarder (
8.8.8.8) is a windows machine ... which it is not.Is
8.8.8.8setup as a forwarder in DNS or actually configured on the NIC?If your DNS servers are setup correctly (with forwarders on your DNS server), you do not need to add external DNS servers to your NIC configuration. Otherwise Windows appears to assume that your DNS servers configured on the NIC are other Windows servers and tries to connect via DCOM (e.g. not using DNS but the DCOM serialized objects)
A brief guide on setting up forwarders on your 2012 DNS server
On a side note, it would be better to add your ISP DNS servers before
8.8.8.8on your forwarders, unless your ISP services exhibit higher latency in lookup times. Generally the DNS queries will be dominated by the RTT of your network, so the closer the better. But you will need verify with testing first.