Why is the CNO in a Failed State?

Hello, my name is Steven Graves and I am a Support Escalation Engineer (SEE) in the Platforms Support group here at Microsoft. One of the technologies I support is Windows Server Failover Clustering. I’d like to take a couple of minutes to share some information on an issue I previously worked on. The customer wanted to create an Exchange 2010 DAG, which would be the first Windows Server 2008 R2 cluster in their environment and they were having issues bringing the CNO online after the cluster was created. The customer domain was originally 2003 and they had to add a 2008 R2 DC and update the schema in order to install Exchange 2010 DAG.

For starters, since I knew the CNO was not coming online after creating the cluster I had the customer destroy the cluster, pre-staged a new computer object for the CNO then created a new cluster based on the name of the new CNO. After the cluster was created I noticed that the computer object was still disabled in AD and the following error message in the cluster log.

00000e80.00000d5c::2012/03/14-16:07:33.149 INFO [RES] Network Name <Cluster Name>: Trying to find computer account W2K8R2Cluster object GUID(cae8b3dcc60aa040bbcef250634427bb) on any available domain controller.
00000e80.00000d5c::2012/03/14-16:07:33.306 WARN [RES] Network Name <Cluster Name>: Search for existing computer account failed. status 8007052E
00000e80.00000d5c::2012/03/14-16:07:33.352 WARN [RES] Network Name <Cluster Name>: Couldn't get information from DC \\Info-dc3.infoimage.com. status 5
00000e80.00000d5c::2012/03/14-16:07:33.352 INFO [RES] Network Name <Cluster Name>: Trying to find object cae8b3dcc60aa040bbcef250634427bb on a PDC.
00000e80.00000d5c::2012/03/14-16:07:33.462 WARN [RES] Network Name <Cluster Name>: Couldn't get information about PDC. status 5
00000e80.00000d5c::2012/03/14-16:07:33.462 INFO [RES] Network Name <Cluster Name>: Unable to find object cae8b3dcc60aa040bbcef250634427bb on a PDC.
00000e80.00000d5c::2012/03/14-16:07:33.462 INFO [RES] Network Name <Cluster Name>: GetComputerObjectViaGUIDEx() failed, Status 8007052E.

‘Access is denied’

In the System Event log you will see an ID 1207 that should be in synch with the time in the cluster log. The main thing to focus on is the “Unable to get the Computer Object using GUID”.

Log Name: System
Source: Microsoft-Windows-FailoverClustering
Date: 3/14/2012 9:07:10 AM
Event ID: 1207
Task Category: Network Name Resource
Level: Error
Keywords:
User: SYSTEM
Computer: W2K8R2Cluster.Corp.com
Description:
Cluster network name resource 'Cluster Name' cannot be brought online. The computer object associated with the resource could not be updated in domain 'infoimage.com' for the following reason:
Unable to get Computer Object using GUID.
The text for the associated error code is: Logon failure: unknown user name or bad password.

At this point, I’m pretty convinced there are some issues with the GPOs on the domain controllers but I still need to do my due diligence in troubleshooting the issue with the Cluster Network Name in a failed state.

Since I pre-staged the CNO and it was still disabled after creating a new cluster, this gave me more evidence indicating an issue with the DC. I created a new OU and blocked inheritance in order to prevent any GPOs from being applied to the Node(s). I refreshed the GPO’s on the Node(s), confirmed there are no GPOs applied by running Gpresult /V from an Administrative CMD Prompt, but the Cluster Network Name still fails to come online. I’m convinced there is some issue with GPO’s on the DC but I’m not sure where to start looking.

Next, I verified the permissions in AD on the CNO and, to be on the safe, I granted the CNO Full Control to the object and also confirmed that the CNO has the correct permissions to the OU(READ permissions on the OU should be sufficient rights to access the OU and get to the computer object). Despite this, the Cluster Network Name failed to come online.

I moved on to check the DNS Host A record for the CNO not really thinking this is the issue but more or less making sure everything is in order. I came to find out a Host A record was not created for the Cluster Network Name because they do not have Dynamic Updates enable for DNS. I created the Host A record and checked off “Allow any authenticated user to update the DNS records with the same owner name.” I already knew the node was able to resolve the DC from the warnings in the cluster log but couldn’t get information from DC \\W2K8R2-DC.Corp.com. So it was not a name resolution issue trying to access the DC.

At this point, I have gone through all the normal troubleshooting steps that generally resolve the ID 1207 and the CNO in a failed state from the cluster perspective. Now it’s time to engage Directory Services to take a deeper look at the DC configuration. After some time reviewing the Domain Controller configuration and GPOs the DS engineer narrowed it down to permission issues in the “Access this computer from the network” policy. The default permissions are pictured below.

Access this computer from the network - This user right determines which users and groups are allowed to connect to the computer over the network. Since "Everyone" and "Authenticated Users" were missing from the settings, this meant that no computer would be able to access the domain controller.

Picture above shows the default permissions for the Access this computer from the network policy

The DS engineer modified the “Access this computer from the network” policy in the Default Domain Controllers policy by adding Authenticated Users, refreshed GPOs by running GPUpdate /force, ran RSOP.msc to confirm the GPO is applied, and the CNO came online.

Steven Graves
Support Escalation Engineer
Microsoft Enterprise Platforms Support

Comments

• Anonymous
  November 12, 2015
  Great post from your hands again. I loved the complete article.
  By the way nice writing style you have. I never felt like boring while reading this article.
  I will come back & read all your posts soon. Regards, Lucy.