We were faced with a deleted computer object/cluster name object/cluster resource for one our SQL clusters.
The lovely error message confirmed why the cluster was in an offline state:
Cluster network name resource ‘SQL Network Name (XXXXXSQLCLUS01)’ cannot be brought online. The computer object associated with the resource could not be updated in domain ‘XXXXXXX.com’ for the following reason:
Unable to get Computer Object using GUID.
The text for the associated error code is: There is no such object on the server.
The cluster identity ‘XXXXXXXXXXCLUS01$’ may lack permissions required to update the object. Please work with your domain administrator to ensure that the cluster identity can update computer objects in the domain.
Immediately knowing that this is a serious problem we went about to see how we can restore or recreate the deleted object. As we do not have Active Directory Recycle Bin – restoring was out of the question. So the second best thing (and thankfully available) was this TechNet article.
While the TechNet article was exactly what we were looking for we decided to tweak it a little. Instead of creating the CNO in AD and setting the GUID we simply did it the other way around. Created the CNO in AD and updated the registry on both nodes of the CNO to the new GUID from the newly created AD CNO.
Re-create the Cluster Name Object in Active Directory and navigate to the ojectGUID under Attribute Editor:
On one of the cluster nodes navigate in the registry to HKEY_LOCAL_MACHINE\Cluster\Resources where you will have to either search automatically or manually for the missing Cluster Name Object – it should be under Parameters in one of the GUIDs:
Once the correct registry entry has been located for the deleted CNO, we copied the objectGUID hex value from Attribute Editor in AD of the newly created CNO and pasted it (without spaces) into the ObjectGUID registry key of the relevant CNO:
If everything went to plan you should be able to bring it online: