An unknown error occurred while validating the server

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An unknown error occurred while validating the server
Can't find yahoo.com: Query refused

Our DNS servers are running on Windows 2008 DC. We have some DNS issues. When I check the Forwarders in the DNS Manager, it shows Comcast DNS "An unknown error occurred while validating the server"

If I run nslookup, I get can't find web site: Query refused

nslookup

Default Server: 2008.chicagotech.net

Address: 10.0.0.17

> server 68.87.72.130

Default Server: chic-cns.area4.il.chicago.comcast.net

Address: 68.87.72.130

> yahoo.com

Server: chic-cns.area4.il.chicago.comcast.net

Address: 68.87.72.13

*** chic-cns.area4.il.chicago.comcast.net can't find yahoo.com: Query refused

I have opened a case with Comcast, the technician said their DNS works fine. If I test it from my home, the nslookup can query the web site uisng Comcast DNS. The Event Viewer doesn't have any error related to the DNS. How do you troubleshoot it?

From the description, I understand the issue is that nslookup failed with error "query refused" and your ISP DNS server shows as "An unknown error occurred while validating the server" in DNS forwarder list. If I misunderstand, please don’t hesitate to let me know.

Do you have configured a primary or secondary zone in your DNS server for comcast.net? If so, since you have already had DNS forwarder configured, you don't need to configure any zone for comcast.net, I suggest you delete it if any and test again.

Also this issue could be caused by the incorrect DNS cache. I suggest you run the command below on this Windows 2008 server.

Net stop netlogon

net start netlogon

ipconfig /flushdns

ipconfig /registerdns

After that, please test again. If the issue persists, please help me gather the following information:

1. Please help me gather the debug logging for DNS.

a. In DNS console, right click the DNS server and go to Debug Logging tab.

b. Select "Log packets for debugging" and select all the available options.

c. Specify a log location.

e. Reproduce the issue and gather the debug log, then disable the debug logging.

2. Please collect MPS report on the server (PFE version) for the analyzing. The MPS Reporting Tool is utilized to gather detailed information regarding a systems current configuration. The data collected will assist me with fault isolation.

=====================

a. Please download MPS Reporting Tool from the following link:

(http://www.microsoft.com/downloads/details.aspx?FamilyID=00ad0eac-720f-4441-9ef6-ea9f657b5c2f&DisplayLang=en)

NOTE: The link may be truncated when you read the E-mail. Be sure to include all text between '(' and ')' when navigating to the download location.

b. Right click MPSRPT_PFE.EXE and select Run as Administrator to run this tool, and you will see a Command Window start up.

c. Please type Y with the message of <Include the MSINFO32 report? (defaults to Y in 15 seconds)[N,Y]?

d. When the tool is done you will see an Explorer Window opening up the %systemroot%\MPSReports\Setup\Reports\cab folder and containing a <Computername>MPSReports.cab file.

e. Please check the log file for any errors

Q: 1. Do you have configured a primary or secondary zone in your DNS server for comcast.net? - I don't think so. We have only one DNS zone that is setup for LAN or I should say we setup DNS zone for our internal DNS IP addresses only and we ISP DNS in teh Forwarders.

2. Those commands don't make any differnece and we still get Can't find web site message.

3. I will send log to you later.

4. I tried to run MPSRPT_PFE.EXE. It runs for just seconds and the blue screen disappears. I don't see MPSReports folder under windows and I search <Computername>MPSReports.cab, but can't find it.

A:

From the netmon log, we can see the following DNS query.

1622 32.265625 {DNS:230, UDP:229, IPv4:160} 2008DC2 68.87.72.130 DNS DNS:QueryId = 0x3, QUERY (Standard query), Query for yahoo.com.chicago*******.org of type Host Addr on class Internet

à This is the DNS query package sent to the remote IP

1623 32.281250 {DNS:230, UDP:229, IPv4:160} 68.87.72.130 2008DC2 DNS DNS:QueryId = 0x3, QUERY (Standard query), Response – Refused

à This is the DNS query response that the remote IP sent back to your Windows 2008 server.

From it we can see that it is the remote IP address send refused response to your server, this should be the remote side issue. Looking into the details of the frame above.

We can see the source is from a Cisco system device. It appears to be your ISP's router, if in this case, you may need to contact ISP to see whether they router has declined your DNS server's request.

SourceAddress: Cisco Systems 54C725 [*MAC address*]

In addition, I also found this Windows 2008 server in question is installed on VMware platform as the destination address is DestinationAddress: VMWare, Inc. 8F3C2D [*MAC address*]

I'd like to point out that if the system environment is in the hardware virtualization software, such as VMWare, due to the difference(s) between virtual environment and physical hardware, it will be difficult for us to investigate the technical problem effectively. Therefore, we don’t support such Windows system on VMware environment. For more information, you can refer to:

Microsoft server software and supported virtualization environments

http://support.microsoft.com/kb/957006

Support policy for Microsoft software running in non-Microsoft hardware virtualization software

http://support.microsoft.com/kb/897615

I would like to suggest you use Hyper-V on Windows 2008 server to host your virtualized system or use a physical server instead. More information about Hyper-V, you can refer to:

Virtualization TechCenter

http://technet.microsoft.com/en-us/virtualization/default.aspx

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