Backup Exec Hyper-V Agent backup to disk job is unable to mount a VHD that resides on a physical disk with a 4KB sector size

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Problem

In Backup Exec 2012 and above, a Hyper-V Agent backup to disk job completes with an exception stating Backup Exec is unable to mount a VHD that resides on a physical disk with a 4KB sector size.  This issue occurs when the backup to disk folder is located on an Advanced Format 4K Sector drive.  Typically these drives are 2TB or greater.  Additionally the issue can occur with NAS devices or storage arrays that format or emulate volumes with 4K sectors.

 

Error Message

Backup Exec is unable to mount a VHD that resides on a physical disk with a 4KB sector size.  Backups that were enabled to use Granular Recovery Technology will not be available to be restored from this backup set.

 

 

Cause

In order to perform a GRT backup to disk, Backup Exec must be able to mount the VHD files on the Backup Exec media server backup to disk location.  Due to Microsoft limitations Backup Exec is unable mount and access VHD files on Advanced Format 4K Sector drives or volumes. See Additional Microsoft Links below.

Using Hyper-V with large sector drives on Windows Server 2008 and Windows
Server 2008 R2
http://support.microsoft.com/kb/2515143

Information about Microsoft support policy for large-sector drives in Windows
http://support.microsoft.com/kb/2510009

 

Solution

Workaround:  (Use any of the following)

  1. Perform a Non-GRT backup. 
  2. Perform a Remote Agent backup of the Virtual machine using the Backup Exec Remote Agent (RAWS) or Agent for Windows Servers (AWS).
  3. If possible format the backup to disk drive to 512K sector size or 512E (Emulation) if the hardware vendor provides a tools for format or 512k emulation.

 

 

Applies To

Backup Exec 2012 or above
Hyper-V Agent
Backup to disk with GRT enabled

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Backup Exec 2010 Hyper-V agent GRT enabled Backup to disk jobs targeted to Advanced Format 4K Sector disk drives complete with exception

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