Storing Virtual HDD as multi much smaller files than 2 GB

O

Olivier

Forum Maven
This would be similar to the technique used by Apple for implementing the sparsed bundles of Leopard. One advantage I see would be quick backup updates of the whole virtual machine when using techniques like Time Machine or SuperDuper.
 
I know John for the 2 GB chunks and I used it on some VMs. Though a smaller chunk size would be much better for backup reasons. There is probably some tradeoff to find. 8 MB chunks like Apple sparseBundle might be too small leading to too much files to play open/close with for performance reasons. Yet, if I create a sparseBundle, mount it, copy my VM in it (disk is single file) and run it from there, my personal usual tasks benchmark show **only** 5 to 10% slowdown. I guess that using bands larger than the sparseBundle 8 MB typical size (but yet below 2GB) might be better.

Please keep in mind that when I talk backup I always assume VM stopped.
 
Solution: Driver on OSX side that offers OSX folders as NTFS disks...

Solution: A driver on OSX side that offers OSX folders as ntfs disks to the VM. This way everything could be backuped without any problem with Timemachine...
I really don't see any license problems here. That is what you've told me in response when I suggested such a feature during beta testing.
Please rethink. This feature has been suggested for the free virtualization software from SUN.

uli
 
Hello biglar.
This is not a sharing problem, it's a backup problem. Right now Parallels recommends not to backup VMs with timemachine because TimeMachine has to backup everything, not just the changes you make and working with 2GB splits doesn't seem to be an adequate solution either. For this reason it would be great if you could simply use an OSX folder as Virtual Disk. On OSX side TimeMachine would simply backup changes within the folder and not a whole VM disk or splits.
 
uidepara said:
Hello biglar.
This is not a sharing problem, it's a backup problem. Right now Parallels recommends not to backup VMs with timemachine because TimeMachine has to backup everything, not just the changes you make and working with 2GB splits doesn't seem to be an adequate solution either. For this reason it would be great if you could simply use an OSX folder as Virtual Disk. On OSX side TimeMachine would simply backup changes within the folder and not a whole VM disk or splits.
Click to expand...
And it would not work.
Or to be more precise: the time machine backup would work, but the backup would not be a valid snapshot of the virtual machine disk(s).
To get it to work, you would need the virtual machine to be stopped when Time Machine backs it up. This would need some collaboration between Parallels and Time Machine, such that when the VM is started TM CANNOT ever backup any part of it, and only do so when VM stopped.

I wasn't discussing a "problem" initially, just making a proposal.

Today, to backup a Windows VM, the very best thing to do is to use Acronis True Image Home (included with Parallels 4). You can direct the backups through a Shared Folder to a Mac OS X folder on the native disk, where it will then be taken up by Time Machine.
 
I believe uidepara want to use backup inside virtual machine, if yes it is possible
you need to locate it /tpm/xxxx/C xxxx is some digits
But it is from mac OS to backup VM
 
Hello Olivier.
My proposal is to get rid off the VM as a separate storage: the VM would be nothing more than a configuration file, that defines something like "use folder /Volumes/mydrive/mywin" as the storage folder for everything needed. A driver exposes a mbr and everthing else needed to boot a windows system in the right place but stores the data directly within a normal folder. This should be possible. Once this is working TimeMachine can backup the data within the folder and you can instruct TimeMachine to exclude unnecessary folders like temporary folders. It's all about exposing to a windows system the necessary information to make it believe that it's working on a real harddisk. The current VM's do something similar: they expose a virtual hard disk based on one file (or 2GB splits). What's happening inside of this file is completely handled by the Guest Operating System. Is it really impossible to implement a solution that allows the Guest Operating System to be installed inside a normal OSX folder? I don't think so.
 
Hi John.
/private/tmp/ will be created in a TimeMachine Backup but all the contents (subfolders and files) are excluded by default in TimeMachine. I simply want one! clean solution to backup my work. Not one inside of VM (acronis), another on Mac (timemachine).
 
I am actually trying to figure out, what actually I can submit as feature request
-What you want is XEN domain solution,
- We have clone , or simple copy for VM
- or my last suggestion
Also you mentioned Virtual Bix, could you please refer to some documentation, I am not familiar with the latest version of Virtual Box
 
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