Mac Backup Strategy?

[steveroberts1]

Hello, I'd like to back up my VMF virtual machine daily. I'm using a Mac and have read that TimeMachine is not a reliable VM backup. Is there a way to automate with Carbon Copy Cloner or some other software Thanks for any advice/recommendations you can provide. SR

[scott28tt]

This is by a forum user: https://www.vimalin.com

[wila]

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@scott28tt wrote:

This is by a forum user: https://www.vimalin.com

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That forum user would be me.

If you have any questions then do not hesitate to ask here or at the designated forum area of the product itself ( Vimalin forum )

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Wil

[steveroberts1]

What a fantastic tool; thanks! In order to run Vimalin, I had to disable auto-protect snapshots. I'm not sure about the ramifications of doing that. Can you please help me to understand what that does SR

[wila]

Hi,

Thanks for the compliment.

An auto protect snapshot is an automatic snapshot mechanism in VMware Fusion. It will trigger a snapshot on a predetermined time and keep N snapshots around.

Vimalin also uses snapshots.

In order to make a backup of your VM while it is running, Vimalin will make a snapshot before it starts copying files and then remove that snapshot once all files have been copied.
As VMware currently does not have a mechanism to temporarily pause auto-protect snapshots.

This is a problem when a backup is running and auto-protect kicks in. When that happens there are changes made to a several files and your backup would no longer be correct.
Not only would a new snapshot mess up several files, but the "keep N snapshots" around would also remove files that Vimalin is trying to copy. All in all.. very messy when that happens and the only way to prevent that atm is by disabling auto protect.

So yes, you loose auto-protect, but as you now have full backups, you shouldn't need auto-protect any more. Also note that having multiple snapshots open at all times does also slow down your VM. It depends a bit on how many snapshots and the host hardware on how noticeable that is.

This testimonial might also help: https://www.vimalin.com/must-have-utility/  That user also used auto protect before and he was pretty happy with the result after disabling that feature.

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Wil

[gilby101]

There are two issues with using Time Machine, Carbon Copy Cloner, Chronosync, etc.

1) These backup utilities take a snapshot of the file system. This ensures that when it comes to recovery you have files from a single point in time with regard to the file system - so you will get a reliable restore as far as the file system is concerned.  But the content of the files (particularly virtual disks) is not at a snapshot as far as the virtual machine  is concerned. What you have is as if the VM had crashed at the time of backup - most likely a restored virtual machine will restart, but maybe not. Note this is only an issue for running VMs.

2) Time Machine keeps backups for multiple points in time (hourly, daily, weekly). Your documents, photos, etc. don't change very often so these multiple backups do not consume extra disk space. But virtual machines are a) large and b) changing all the time. When backed up (every hour) each backup will be different and so consumes disk space. For other utilities it depends on how you have them configured regarding how much history is retained. CCC is very like TM in its default configuration.

To manage the first issue you need a way of taking snapshots at the virtual machine level. This ensures that vm data has been flushed to disk and that the virtual file system is in a consistent state. Vimalin is a great way of automating the taking of virtual machine snapshots and saving them as backups on a different disk. I use Vimalin for my active virtual machines. For inactive VMs making copies is probably just as good depending on your risk profile.

To manage the second issue (consuming lots of backup disk space), you need to decide if you really need virtual machine backups going back many months as produced by TM or CCC. For my active VMs I am happy to have daily vm snapshot backups for a week. This is easily done with Vimalin. But you need to consider your own risk profile as to what you can afford to lose and for how long in the past you might need to go back.

For VMs which I know will be shutdown or sleeping at night, I am satisfied with a single copy as backup (accepting the risk that I may be keeping corrupt or unstable VMs). I automate this with Chronosync. Again, think about what the risks are to your VMs (particularly consequences for you of any failures).

OR, take an alternative strategy. Use tools running within each virtual machine to create backups - shared folders (on a different physical disk) are a great location for them. Now recovery involves re creating the virtual machine and then (within the VM) restoring apps and data from the backup.

[Technogeezer]

There's a related issue with Time Machine if your VMs reside on an APFS disk.

Time Machine takes hourly local snapshots of all APFS volumes that it is going to back up, and those are kept for about 24 hours. If your VM resides on one of those volumes, an APFS snapshot is taken regardless of whether you have included or excluded your virtual machines for Time Machine backup. That's extra disk space taken up on those volumes, especially if the VM is running and writing to its virtual disks at the time of the Time Machine backups.

One solution to this I've seen (and used) is to create an additional APFS volume on the same container (disk) and store your VMs there. Do not enable Time Machine for this volume. The VM volume will share the available pace with the other volume that contains the rest of your files, but won't have APFS snapshots taken that waste space. 

[ColoradoMarmot]

I've had this issue when using virtual machines while traveling - sucks down free disk space, and the auto-cleanup when detached from the TM volume doesn't seem reliable.  Often I'll go into CCC and delete all the local snapshots (or do it from terminal) if I'm away from the real drive for a while to free up space.  Even with the TM volume attached, it can take a while for the auto-cleanup to run.