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Just thought I'd share some recent experiences with Backup Exec 2012 SP2 & Hyper-V 2012.
I have been using Backup Exec since the Veritas days, am a VMware VCP and worked for Microsoft for many years as a 3rd level tech.

This article is specifially addresses some design considerations around planning your Hyper-V environment with regards to using the Hyper-v (Formerly the AVVI) agent and GRT.

Being able to backup and restore whole machines and recover individual items, such as mails, databases and files reduces bot the number of jobs, but the amount of time required to backup. Some of the suggestions you may see in regards to fixing issues involve disabling GRT, which would then mean you would have to backup much of the data twice. So these suggestions are to help you ensure that GRT works.

Firstly and obviously, backups intended for GRT recovery must be done to disk. This disk should be local and fast. Placing this on an iSCSI LUN for example means that data can be flowing over the network twice. As Backup Exec 2012 SP2 does not yet support SAN (back end) backups, this would probably be going over the same interfaces. There are a host of other reasons for having this local, but won't go into it more in this discussion. Like GRT backups have always been, if you do them direct to take, you will need to reserve space of your biggest datastore on the backup server to copy the whole resource back, before you can restore the file or mail etc. Meaning it could take hours to restore a 1mb file or mail. Obvious part over.

As we had issue in the past with thin provisioned disks and volumes filing up and blue screen servers that then required many hours of rectification, I configured them as THICK or FIXED (Hyper-v terminology)

Backup Exec 2012 SP2 now fully supports VHDx (Fixed or Dynamic), but I had already configured all the VMs as VHD fixed.
I wasn’t too concerned, but noticed that the VM Incremental backups were taking way too long. Almost as long as the full backups.Then found that because of the fixed disks, this was how Backup Exec works. It will always backup the whole amount of data.

So to cut a long story short, I am converting all the VMs to Dynamic VHDx
This is in fact;

Copy the VHD to a VHDx Dynamic
Reconfigure the VM to use the new disk
Test the VM.
Delete the VHD.

So quite an effort requiring more disk space and donwtime.
Covered here;

But DO NOT USE 4k (4096) Sector size.
As stated in the Backup Exec 2012 SP2 ReadMe
“GRT is not supported for virtual machines that have VHDX image files with a logical sector size of 4096 bytes. This applies to both application-level GRT and file/folder-level GRT. A full restore of a virtual machine with that configuration can be performed”

Two last things

Don’t Confuse Dynamic VHDx disks with Windows Dynamic Disks.
Use basic disks in Windows, not Dynamic
“GRT is not supported for virtual machines that use dynamic disks, such as spanned, mirrored, striped, or RAID 5 disks”

And do not use VHDx files over 2TB (make them 1.9TB)
“If a virtual machine has only VHDX files, file/folder-level GRT and application-level GRT are supported if the VHDX has a capacity of less than 2 TB”

So in summary, to be able to use VM backups in Backup Exec 2012 SP2 with GRT

Disk Format


Disk Type


Sector Size


Max Size


Windows Partition Type


Any changes or suggestions welcome.




...good information! Thanks for sharing!