With the help of Alan Renouf’s vCheck (Daily Report) script I recently started noticing an error in my Windows event log on a vCenter server.
This directory partition has not been backed up since at least the following number of days. Directory partition: DC=virtualcenter,DC=vmware,DC=int 'Backup latency interval' (days): 90 It is recommended that you take a backup as often as possible to recover from accidental loss of data. However if you haven't taken a backup since at least the 'backup latency interval' number of days, this message will be logged every day until a backup is taken. You can take a backup of any replica that holds this partition. By default the 'Backup latency interval' is set to half the 'Tombstone Lifetime Interval'. If you want to change the default 'Backup latency interval', you could do so by adding the following registry key. 'Backup latency interval' (days) registry key: System\CurrentControlSet\Services\NTDS\Parameters\Backup Latency Threshold (days)
This error only occurred in one of the three vCenter instances I manage. After checking with my enterprise backup team and confirming this server does get backed up on a regular basis I opened an support request (SR) with VMware Tech Support. Two weeks later VMware technical support finally contacted me about my SR. The response: since the error occurs as part of the ADAM/LDAP instance that comes with the underlying operating system please contact your Operating System vendor for support. After waiting as long as I did for an initial response I had higher hopes for an actual solution.
I started Google-ing for solutions on backing up the ADAM/ADLDS instance on my own. I found an excellent article on how to do this in powershell at http://www.open-a-socket.com/index.php/2009/04/21/schedule-backups-of-your-ad-lds-instance-using-dsdbutil-2/. Here is the actual script that I now run as a scheduled task:
$vcenter = "vcenter.host.name"
$date = Get-Date -Format yyyy-MM-dd
$backpath = “D:\ESXiBackup\$vcenter\$date\”
#Create a backup of the ADAM Instance VMwareVCMSDS
$cmd = $env:SystemRoot + “\system32\dsdbutil.exe `”ac i VMwareVCMSDS`” ifm `”create full $backpath\#VMwareVCMSDS`” q q”
Now that I have my own VCMSDS backup — and no errors in the event log — I can sleep better at night.