ISSUE
You perform a File Level Recovery of a VM and when choosing an item to restore from the File Level Recovery Object, you receive a message of:
"No files qualified (softlinks are excluded) for the download."
In addition, the data you see in the FILE BROWSER by clicking Browse/Download does not match the CIFS file share. The CIFS will only show a Thumbs.db.
RESOLUTION
This issue is caused by Microsoft's native file system deduplication. The filesystem of a deduplicated volume can only be read directly by another Microsoft OS that also has the deduplication feature enabled. Such a configuration is not possible within an FLR image as we are reading the NTFS data directly and windows itself is not running or active. All backup providers have this limitation when accessing VM data for deduplicated file systems.
There are two options to perform successful recoveries of this data.
- Recommendation: Disable the Microsoft Native deduplication for Windows 2012R2 for primary data sets that are directly backed up. Deduplication is best used for redundant copies in DFS roots and not the originating live data sets due to recovery risks and computational overhead that generally exceed storage costs of not deduplicating. Note, after disabling deduplication it is necessary to force the volume to fully rehydrate manually to remove existing deduplicated data sets. Please see Microsoft documentation for this process, or for their best practices on when you should and should not be using their native deduplication technology, Unitrends Support staff cannot directly assist in modification of the settings on your windows servers. It is not recommended to use Native Dedupe inside of virtual machines.
- Continue with Windows Native Deduplication, but form a backup strategy that supports it and test the restores to determine the restore times and limitations.
- You may continue using host level (VM backup) protection for OS and critical disks that are NOT deduplicated on VMWare host systems. Discontinue VM disk backup for deduplicated volumes on VMWare. Discontinue guest backups of this VM for all pother hypervisors entirely. Note, when excluding VM disks in VMWare, it is important to ensure the server will successfully boot with the missing volumes and this should be tested. In many cases Windows may have inter-volume dependencies that prevent operation for non boot disk critical volumes.
- You will need to install the Unitrends Client Agent into this Guest VM. Backup up at the minimum, the deduplication disks using the agent. If you are not using the agent to back up the OS disks, exclude the system state option from the advanced backup options for this client. - Continue using VM backups, but be aware FLR recovery is not possible using CIFS for this system. To perform granular file level recovery, FLR using iSCSI will be required. As the original system cannot connect to it's own prior existing volume copies using iSCSI due to volume UUID conflicts, a separate windows server will be required to access this data, and that server must support Windows native Deduplication. This should be tested prior to need and may require Microsoft assistance to perform. Unitrends Support cannot help re-connect a new server to existing deduplicated volumes should trouble arise.
- Perform full recovery of the original VM to a new VM in parallel with the production server. Ensure you remove the restored server copy from your production network before powering it on and access the server on a maintenance or management segment to access files in that file system from prior backups.
Note of warning: The restored data from the Client Agent backup is NOT deduplicated. Native deduplicated volume data is provided to backup vendors fully rehydrated. This means a restore of a deduplicated volume will be fully rehydrated (original size). Customers who are using native deduplication to ensure data fits within an existing disk that it would not fit in without native deduplication are at GREAT RISK of being unable to completely restore a server in time of need. Please see Microsoft best practices on when to use and when not to use windows native deduplication to ensure you are not impacted by this risk.
Backups of deduplicated volumes will take an extended time and may require more resources to process as Windows must process these files to provide them to backup vendors, they cannot be backed up in their native deduplicated state directly, and this will often incur larger incremental change as well.
CAUSE
The native deduplication capabilities of Windows 2012 R2 have been enabled for the Disk you are trying to restore from. Deduplicated files are not stored as true files, but offline file reference points that require database interaction to read and reconstruct. It is not possible for 3rd party systems to read NTFS volumes and access Microsoft's native deduplication database architecture as that is a proprietary system. As such, Windows native Deduplicated volumes in virtual machines cannot support granular FLR directly. To confirm if this setting is on, see the below image.