Azure Hybrid & Cloud Migration Blog

Author: Zahir Hussain Shah, MVP Exchange Server, CISSP

Recently, I saw a situation, where on the Exchange Server 2010 Mailbox Database LUNs (Disks) are running out of free-disk space, and upon inspection, we found that other than Mailbox Database and Logs folder, there is some hidden data, which is consuming the free-disk space, and it is not seen able, so I got to recall the Disk Shadows problem, for which I wrote an article (Exchange 2010 VMs on Hyper-V Server are stopped due to unavailability of free disk space | Hyper-V Server is running out of free disk space on the Server) in past, where using VSS based Backup tool is failing to delete the VSS snapshot files from the disk (volume), after successful or unsuccessful backup jobs.

Okay, so what is happening here, we will see in the following section:

Problem / Cause:

When you use VSS based backup tools, like Symantec Veritas NetBackup, which uses VSS to take the snapshot (backup) of the required data, and where sometimes due unsuccessful backup jobs, and file locking (antivirus cause) problem, in some circumstances, VSS backup tool / VSS Service fails to delete the temporary files from the Disk (LUN), or in other words, you can say that due to the failed backup jobs, VSS creates the snapshot temporary files in the DISK, and which over the time eats your available free disk space.

Symptoms:

If you want to see how these files look like, you can go to the drive, e.g. E:\ make sure the hidden files are unchecked, open System Volume Information, and there you will see all these temporary created files, like <99898-8888-xxxx-xxxx>.

Solution:
For bring this consumed free disk space, lets do the following for removing these Volume Shadow copies:

1) Open CMD with RUN AS ADMINISTRATOR
2) First list the available generated shadow copies by running the below command:

DISKSHADOW

Since now you are on DISKSHADOW prompt at command prompt, lets list all the available shadow copies by running the below command from the DISKSHADOW prompt:

LIST SHADOWS ALL

Upon running the LIST SHADOWS ALL command, you will see all the shadow copies, so then you can run the below command from the same DISKSHADOW command prompt for deleting these shadow copies:

DELETE SHADOWS ALL

And now you can go back to Windows Explorer, and can evaluate your available free disk space, and will glad to see that all your hidden consumed disk space is back now. :)

I hope this will resolve your problem, and will help to stay relax from being tense to see your Hyper-V Servers (or any Server) physical disk free space getting consumed by hidden stuff.

Cheers!