Options for Backing Up a Virtual Cluster with Shared Drives

  • 23 September 2022
  • 4 replies

Userlevel 1
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We recently upgraded our Physical cluster to a Virtual Cluster.  In doing this we had to have the have the windows cluster with shared SCSI Bus for it to Failover.  We have no way to get around that.  CV does not back the VMs up with the following error.  “Virtual machine [Blah] is configured with shared virtual disks. Snapshot operations are not supported for shared disks. Use an in-guest agent to protect virtual machines with shared disks.”  I had opened a ticket with CV and they stated this is because the Snapshot can’t be created and recommended a Windows File System iDA.  My question is does anyone have any recommendations for a solution to get this cluster backed up, that is easy to restore onto our appliance in a Disaster situation?  I am guessing that would be an in-guest agent or the Windows File System iDA, but I honestly don’t know what that means or how to accomplish that.  Any suggestions would be great as we are hanging in the wind with these not getting backed up.  I will also gladly open a full ticket just figured I would throw it out here first.  Thank you.

4 replies

Userlevel 6
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Hi @Heath 

Unfortunately VM backup is not an option in this setup.

The in-guest agent and file system IDA are the same thing.

You can download a media kit from Commvault or connect to the software cache on your Commserve or push install via the commserve.

You need to install the file system core agent and the file system agent within your OS and backup the drives you need combined with the system state.

When installed and subclient configured assign the subclient to a plan or storage policy. In case of a storage policy assign a schedule or scheduled policy to backup automatically.

When a DR restore is needed you either need  1-Touch enabled (before you backup) on the client in order to use 1-Touch ISO for a baremetal restore, mount the ISO to a VM and follow the wizard.

Or deploy a VM with OS, configure it, install the agent and restore in-place.

Userlevel 1
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Hi @Jos Meijer 

Thanks for the quick response.  I just have one question, in 27 parts lol.

Kidding aside the way I am understanding is basicly I am going to install the software for commvault like I would on a physical server and backup the C Drive and also the system state.  Then when I go into a DR or DR Test I can make the VM with the same basic size as what we had and install the software and just restore the C Drive and the system state and it will work just like it did before?  Or I enable 1-touch (have to read up on this) and that creates a ISO that we mount into a new VM, just that won’t have the state of the server only the HDD part?

Userlevel 6
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Hi @Heath 

Regarding to size, with a manual in-place restore you are basically restoring the old situation and will end up with approximately the same space usage. This mostly depends on how you might have differently prepared the OS and more files are present then before. For example, certain OS patches, software installers etc are present which weren't before.

With 1-Touch you need at least the same disk size as the original situation. Here the disk is being recovered as it was before.

Regarding functioning as it was, it depends.

In both situations you are recovering to a previous situation so yes, but there are situations where applications (mostly legacy apps) can't cope with recovery based on FS Agent in-place restore. That's where 1-Touch kicks in, combined with block based backups you are backing it up and restoring it differently allowing the legacy application to run properly.

For current systems/apps the recovery in-place should work fine, but testing/validating via DR test is always recommend. You don't want the surprise at a moment where you need the system back online

Userlevel 6
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Additionally some people just don't can't or want to spend time on preparing a VM for in-place recovery. 1-Touch will prevent the need for that as the VM boots directly from the ISO and then recovers the data. Could be a valid choice for this recovery strategy.