Time Machine and SmartGuard

Discussion in 'Installation and Configuration' started by tomfri, Feb 9, 2019.

  1. tomfri

    tomfri Bit Poster

    Yesterday Time Machine saved my life once again even though i strongly suspect it also was the culprit of the crash. I mean, what happens when Time Machine backs up my pvm file while working in Windows...? The last six months i've had the "APFS fsroot tree is invalid" problem twice and the pvm file is to blame. I believe this has to do with Time Machine backing up the pvm file while working in Windows. The first time i formatted my hard drive and started all over again but this time i restored the pvm file after hours of research. Voila, everything works great again. Because of this i added "~/Parallels" to the list of folders Time Machine should exclude. Still i want my virtual machine backed up so my question is about SmartGuard... I have now set the SmartGuard on and ticked the "Optimize for Time Machine" box but the Parallels folder is still excluded from Time Machine. Do i have to include the Parallels folder in Time Machine or are snapshots stored elsewhere? Also i would like to know if someone else have come to the same conclusion as i have?
  2. Maria@Parallels

    Maria@Parallels Parallels Team

    Hi, @tomfri you can just enable SmartGuard as you did. For more info please check https://kb.parallels.com/8827
    Also if you decide to backup your VM please shut it down and plz check this KB for more info about VM's backup.
  3. dvonroeder

    dvonroeder Bit Poster

    tomfri raises some good points and, having had Windows destroy my user account two days ago, this topic has a lot of meaning for me.
    The links provide some cursory information but I haven't found a resource that provides detail.
    It appears that the purpose of SmartGuard is to create snapshots. Per the UI, the number of snapshots and the frequency with which a snapshot can be created is controlled or the user can check the "Optimize for Time Machine". If I understand correctly, the SmartGuard feature deals only with creating snapshots. Is that correct?
    If the PVM is backed up by TimeMachine, TM will create a backup of the entire PVM and will then, assuming that SmartGuard is enabled, will then backup just the snapshots. Is that correct?
    The docs clearly state the PVM should be shut down when doing a backup. That's understandable and, with backup software that could be set to run at "off hours", easily accomplished. An issue arises, perhaps, when using Time Machine because it does an hourly backup. The technical solution is to shutdown my VM's every hour to wait for TM to run but no one could argue that to be a practical solution and keep a straight face. Given that, I have to think that the "shut it down" advice does not apply when using Time Machine or, perhaps, if you're using Smart Guard. Is that correct?
    Maria, could you be so good as to comment on the questions that I've raised?
    Perhaps I'm trying to make too fine a point here but I think everyone would be better served if more information on SmartGuard and backups/Time Machine was available.
    tomfri likes this.
  4. elasticmedia

    elasticmedia Bit Poster

    Forgive me for still being confused. It would be helpful for Parallels to make a youtube video explaining the process of setup and basic explanation of how it works and integrates with Time Machine, both for backup and for restore. It seems that recommended article 8827 is out of date - only mentions v. 13. I see contradictory points in these forums and want to spell it out once again to make sure I have it right and maybe even understand the process. I think I am to include my windows .pvm in the Time Machine backup and I am to check the SmartGuard option in the settings. I gather that Time Machine backups up Parallels but only backs up the small part of it that is the snapshots.
    If I were to restore my .pvm from Time Machine, how would that work? Normally you navigate to where the file/application is stored on the Mac, but if that .pvm file is not backed up, then how would I proceed? What if reinstalled a hard drive and reinstalled Windows: would my backup work there?
    I use Parallels v. 14 with Windows 10.
  5. elasticmedia

    elasticmedia Bit Poster

    The other thing is that if dvonroeder is correct and parallels warns against making a backup while the virtual machine is running, then that essentially means that you can't do automatic Time Machine backups. If Parallels Team could confirm about this point in regards to the danger of the hourly TM backups.
  6. dvonroeder

    dvonroeder Bit Poster

    I heartily concur with the recommendation about creating a video. I wouldn't go so far to say that the hourly Time Machine backup can't be used (I suspect that Parallels is being very conservative) but I certainly don't want to find out the hard way. My approach was to enable SmartGuard and to ensure that Time Machine captured the initial file when Parallels was not running. Smart Guard blocks activity while it's working so it's able to create a valid delta file in the Parallels folder. Time Machine picks up that file when it does a backup.
    This topic is not complex but it's not well documented and, second, the idea that you can exclude your pvm from Time Machine and still be able to recover your pvm file just using the SmartGuard files doesn't make sense to me.
    Parallels users would be well served by up-to-date information on this topic.
    elasticmedia likes this.
  7. TPH369

    TPH369 Bit Poster

    For a few years, I've been using Carbon Copy Cloner to backup the PVMs on a daily or 4 times daily schedule. The VMs are never shut down and the backup PVMs have been fine when I've needed to use the backups.
    I want to integrate this routine with Time Machine so that only incremental backups are required - rather than the entire PVM which takes up time and CPU resources. Hence, I would also be interested in a detailed reply from Parallels regarding the mechanism of Time Machine backups.
  8. RHS

    RHS Bit Poster

    I just found this thread. I'm very curious to know about your "APFS fsroot tree is invalid" issue.
    My ongoing issue is I (and others) have variable size VM files, and when we try to shrink it, the entire Mac OS hangs up and the only way to get it back is to power down. This corrupts the Mac file system as well as the Windows VM. The only thing to do is restore the entire system from Time Machine as well as restoring the VM from backup. Please see this discussion: "Mac host file system corruption during shrinking of PD13 Win10 VM". Your issue sounds familiar. So far I have had a little communication from "Maria" but no relief. I have given up on shrinking the VM file. As far as the VM and Time Machine are concerned, the only way I back it up is to shut down the VM and manually copy the VM file to external storage. I do not trust SmartGuard at all based on what I've been through.
  9. JonasA1

    JonasA1 Bit Poster

    @dvonroeder has asked some VERY valid and interesting questions that I would also like to have the answer to.

    Could someone from the Parallels team respond to them? This would be very much appreciated by many of us.
  10. DavidA36


    Totally agree, there is no direction from the Parallels team as to how to correctly set up Smart Guard. This is unclear as to if it should be set to exclude back ups or not once Smart Guard is enabled. https://kb.parallels.com/8827

    I have it working now, and I *believe* I have it set up correctly, and thought i'd detail my use case. Time Machine was backing up the entire VM with every single back up -50 GB each hour, and it chewed through 2TB of my 8 TB Time Machine back up drive in a a week.

    To fix this, I successfully enabled Smart Guard. Then quit Parallels and forced Time Machine to "back up now". The first time after enabling, TM did another "full" VM back up of 50GB. But once that first one was done, I forced it to do another "back up now" and this one was 75MB and super fast. Each Time Machine back up after that is also just a super fast incremental back up. You can verify that it's working by "entering" Time Machine and navigating to all the VM files.

    In terms of a traditional back up (not Time Machine) that is the one that needs to be done with the VM closed. I use Super Dupe (on a separate external HD) and have it auto run in the middle of the night when I have the VM shut down. Seems to be working fine.

    I *no not* have the VM excluded from Time Machine in the Parallels preferences. My understanding is that it must be included in order for Smart Guard to work - something that is unclear from the docs.

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