Friday, March 28, 2014

Unable to Backup using DPM or Local Windows Backup–missing VSS

Here’s the scenario :

  • Two Windows Server 2012 running Hyper-V
  • Two Node Clusters
  • Backup software : DPM 2012 SP1

When the VM resides on Host1, the DPM can backup VMs with no issue.  However when the VMs resides in Host2, the DPM fails to backup.

Checked on the Host2 and found many errors of 8194.


To isolate further, I tried to backup Folders of Host2 using DPM, it still failed.  Additional to that, tried the Windows Backup locally on Host2, that too failed.

Next is to try a tool which comes in Windows Server 2008 and Windows Server 2012.  It’s called the Diskshadow.

Diskshadow > set context persistent
Diskshadow > set verbose on
Diskshadow > begin backup
Diskshadow > Add volume D: alias VolumeD

The output as follow :


Next I did a comparison of Host1 and Host2 by using the command as follow in the Diskshadow

Diskshadow > list providers

Found out that Host1 has all 4 but Host2 has only 2 of the providers.  The missing ones are highlighted in the pink box.


So go to the following registry in Host1:



Export both the missing key registry from Host1



Then in the Host2, I import both the keys that was exported above from Host1.

In the Host2, I use the Diskshadow to check the providers :


Tried the backup from DPM, and it’s working already.  Hope this helps . 

keywords : Microsoft Hyper-V VSS Writer failed retryable error, VSS Issue error 8194, DPM 2012 SP1, DPM backup fail ,

Creation of recovery points for Backup Using Child Partition Snapshot on have failed. The last recovery point creation failed for the following reason: (ID: 3114)
DPM encountered a retryable VSS error. (ID: 30112)

Monday, March 17, 2014

A VSS Writer has rejected an event with error 0x800423f3

Recently I hit the issue for the DPM backup the VMs.  The DPM backing the Hyper-V VMs failed with the following message in the event viewer of the Hyper-V host that the VM is residing.


Then in the command prompt (elevated “run as administrator”) I list the VSS by typing the command Vssadmin list writers.


In the DPM console, had the following :


The steps that I took to resolve the issue is as follow :

  • Shutdown the VM
  • Perform the VM backup through the DPM
  • In the Hyper-V host, launch the Hyper-V Manager and would be able to see the status as “backing up …”
  • Once the backup is completed in then I start up the VM.
  • Waited for 20 mins for the VM to be up and running, then perform another backup (create another recovery point in DPM)
  • It’s successful and case is resolve.

In the Hyper-V Host I run again the command prompt (elevated “run as administrator”) by typing the command Vssadmin list writers and check the status.


Hope it helps.

keywords : VSS, vssadmin, a vss writer has rejected an event with error 0x800423f3, the writer experienced a transient error, if the backup process is retried, the error may not reoccur, last error : retryable error, Microsoft Hyper-V VSS Writer, DPM encountered a retryable VSS error (ID 30112) , vssadmin list writers