Backup Exec 2010 Hyper-V GRT Issue

So I recently fired up a few new virtual machines in my 2008 R2 Hyper-V cluster for a new project I’m working on. Got everything up and running and set up the new VMs on a backup schedule in Backup Exec. The next morning I went to check to make sure the backups happened correctly, and was greeted with this error:

V-79-57344-38721 – Failed to mount one or more virtual disk images

So the VMs backed up, but the GRT (granular restore) portion of the backup failed, and I wouldn’t be able to recover individual files from the VMs. Searching through Symantec’s KB articles was less than useful (as it often is) so it seemed I had to figure this out myself.

I went over everything I did and didn’t come up with any variation on my normal procedure for creating VMs. However, I realized that these are the first VMs I had created since I upgraded to SCVMM 2012 SP1 from 2008 R2, so perhaps something changed there. I do know that if you’re creating a VM in a cluster, you no longer get prompted to make it highly available, that’s now a checkbox, and if you forget it, the VM creation fails, so that seemed like a good place to start. Well, after checking Event Viewer logs, which were of no help.

So I stepped through the process of creating a new VM in SCVMM paying very close attention at each screen to see if there may have been something I missed. Everything looked good until I got to the Configure Settings portion of the wizard, and I noticed that the vhd files no longer get placed in the same folder as the configuration files by default, they were going to the default storage location for the server they were being created on. So I checked there, and SCVMM had created a VMMDisks folder and all the vhd files for the new VMs were there.

Well, there was something different. So using the Migrate Storage option, I moved the vhd files for one of the VMs back into the folder where the configuration files were and reran the backup job. And no more GRT error.

So it would appear that Backup Exec 2010 R3 is not capable of doing a Hyper-V GRT backup if the vhd files reside in a folder other than where the configuration files are. I’ll just have to make sure I’m manually setting them up in the right place going forward.

5 thoughts on “Backup Exec 2010 Hyper-V GRT Issue

  1. Gosi

    We are absolutely looking into a solution to this for you. SCVMM placing the Config files for the machine on a Physical node and the VHD residing on the cluster CSV… may very well cause a problem..if that’s the case it would most likely be an issue resolved within SCVMM. Backup Exec just queries Hyper-v thru WMI to get the machine info/storage location and takes a snapshot. Please bear with us as we try to reproduce this inhouse. I will forward any and all findings to you.

  2. My name is not Gosi, nor did anyone reply to my tweet, so not sure what that’s about.

    All the files were on the same CSV, but the VHD files were not in the same folder as the configuration files. It’s a cluster, everything has to be on shared storage.

    This happened on Server 2008 R2 using 2010 R3 with all the latest patches applied, backing up to disk.

    Also, I don’t really need to speak with anybody, I figured out how to work around the bug, but thanks for responding.

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