Cannot backup data sources – Volsnap error 39

This week I bumped into a new challenge that I thought I would like to share with the community. A customer reached out to me regarding an error that they couldn’t backup a drive of a server. The D drive was simple not able to be backed up. I looked into the problem and noticed a Volsnap error in the System Log of the DPM server.

The error stated that when DPM tries to create a snapshot of the drive there’s no Shadow Copy Storage available on the drive that DPM protects.

This can easily be solved by using VSSADMIN. Open an elevated commad prompt and use the syntax

Vssadmin add shadowstorage /For=D: /on=D: /maxsize=unbounded 

What VSSADMIN will do is to create a new Shadow Copy Storage for DPM to use.

Can’t make any Recovery Points, volsnap error 39

The DPM software is dependent on the VSS architecture which of course is nothing new. But when it comes to troubleshoot DPM many seems to forget that the initial steps in troubleshooting DPM starts with having a healthy setup of VSS’s present in the affected operating system.

Also its recommended that you verify the System log on the server that you try to protect. In one scenario that I bumped into regarding issues with DPM creating new Recovery Points the local System log was filled with volsnap errors with event ID 39.

In this particular situation the associated VSS area has lost its association to the shadow copy area and therefor cannot create any new Recovery Points.

So how did I soleve it? Well, you need to create a new unbounded shadowcopy area. This is done via this simple set of instrucitnos:

1. Open an elevated PowerShell prompt.
2. If you D drive is not getting any Recovery Points done this is what you type is: “Vssadmin add shadowstorage /For=D: /on=D: /maxsize=unbounded”
3. You can now create a Recovery Point again in DPM