DCOM Communication Error on Domain Controller

Question

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?

Not using Google DNS on the router, and a couple of the other IP's have nothing to do with Google. — Wayne In Yak, Jun 11 '15 at 19:38
Run regedit and search for the 8.8.8.8 ip address. Also check device manager for ghosted network adapters. From the command prompt: Set devmgr_show_nonpresent_devices=1, then run devmgmt.msc. — Greg Askew, Jun 11 '15 at 19:58
Thanks Greg, I did find it in the registry, modified my question to reflect this. Ran the commands you suggested no ghosted adpaters present — Wayne In Yak, Jun 11 '15 at 20:05
This registry path stores [configuration parameters](https://support.microsoft.com/en-us/kb/198408) for the DNS Server role. Is this DC also a DNS server? Do the offending IPs show up in your DNS configuration (e.g. on the *Forwarders* or *Root Hints* tabs)? — I say Reinstate Monica, Jun 12 '15 at 17:53
Yes this server does DNS, not those IP addresses don't show up. This is a Windows Server 2012 too — Wayne In Yak, Jun 12 '15 at 20:39

score 2 · Answer 1 · answered Jun 15 '15 at 05:38

2

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)

It sounds like Wwindows is assuming your DNS Forwarder (8.8.8.8) is a windows machine ... which it is not.

Is 8.8.8.8 setup 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 8.8.8.8 on 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.

answered Jun 15 '15 at 05:38

Joseph Kern

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8.8.8.8 I snot on the NIC card, nor is it to be found in the DNS configuration. The only place it is found is in the registry location I mentioned above. Our other two domain controllers have this same information in their registry but do not show this error. – Wayne In Yak Jun 15 '15 at 13:55
Why don't you amend your question with the actual registry entry you are concerned about, otherwise we are all just guessing what is going on. – Joseph Kern Jun 16 '15 at 06:03
Read my question, the registry entry is listed there... HKLM\SYSTEM\CurrentControlSet\Services\DNS\Parameters – Wayne In Yak Jun 16 '15 at 13:56
@WayneInYak: there are multiple entries under parameters, you didn't say which one. The other DCs don't show this error probably because dcdiag wasn't run on them. (your post suggested the DCOM error was triggered by dcdiag) – strongline Jun 18 '15 at 16:44
What is triggering dcdaig then? These error messages show up every hour on the server. – Wayne In Yak Jun 18 '15 at 16:59

DCOM Communication Error on Domain Controller

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