Concerns about data security

Discussion in 'Parallels Desktop for Mac' started by Khoji, Feb 11, 2007.

  1. Khoji

    Khoji Member

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    I've got Parallels set up and working on with Windows XP on my Mac Pro and apart from problems with Boot Camp everything seems to be working fine. I have no worries about using the Parallels installation for testing but I am still a little hesitant to do any actual serious work in it. Here's why, and I'd be interested to hear if anyone else feels the same way:

    1. A virtual disk is a single file.
      I have two virtual disks, one for the Windows XP installation and one for my data, which is also on a second physical hard drive. However, each of these VDs is just a single file on the hard disk. If anything happens to that file then everything in the VM or the data VD is trashed. On a real Windows installation if something happens to a single file it happens to a single file, not to everything.
    2. Parallels can disappear from the screen and take everything with it.
      If Parallels crashes -- and it is a single program running on the Mac -- it takes the entire operating system and all your data down with it. I already had this happen once with Beta 3120 and it scared the bejeesus out of me. I was moving the mouse past the Parallels window on the desktop with Windows running in it -- I may have clicked somewhere accidentally in passing, I'm not sure -- and suddenly Parallels was just gone, and Windows with it. Poof. Around 30 seconds later a message popped up saying that Parallels had "quit unexpectedly". After restarting XP seemed to be fine but if I had been doing anything serious -- for example a long compile, or working on a big file, the results might have been non-trivial.
    I'm not knocking Parallels -- what it does is absolutely amazing -- these are just basic limits imposed by the way a VM must work. The main Windows application I need to use in XP is a help authoring tool for writing Windows software documentation, and the project files can easily contain over 1,000 pages of text. Thinking of Parallels going "poof" in a puff of smoke in the middle of an editing session is not such a nice idea... The fact that build 3150 just trashed my Boot Camp installation beyond repair also isn't helping my confidence at the moment... :eek:

    Anyone else have any thoughts on this? I know I'm using the betas at the moment for testing so I may be being over-paranoid. OTOH I can remember the bad old days of Word crapping out on long documents in Windows 9x and I really don't have any plans on going through something like that any time soon.
     
    Last edited: Feb 11, 2007
  2. dkp

    dkp Forum Maven

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    1,367
    This is a concern, of course, but also a natural consequence of running virtual machines. The remedy is to make regular backups of your non-running virtual machines to CD/DVD, or tape. Or even to another disk. This will backup your virtual machine, but also your applications and any data that you accumulate in the virtual machine file space. This is only a continuation of what is already a best practice - secure your data through backups.

    In the case of backing up virtual machines you create a new and very useful capability. Your backups can be run on any system that has Parallels installed, so you now have data resiliance, redundancy, and portability on a scale you've never seen before.

    So yes, vm's do put all the eggs in one basket, so to speak, but there's really not much of a downside in pragmatic terms, and so very many advantages and new opportunities.
     
  3. VTMac

    VTMac Pro

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    340
    If you are using boot camp for your VM, all your windows files are on a "normal" partition. They are not all contained in a single files, so I think that concern doesn't apply to you. As for as the "poof", at least when using a boot camp partition, that isn't too much different then a windows BSOD.

    I think your points are valid concerning pure VMs.
     
  4. Khoji

    Khoji Member

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    77
    When the final version with Boot Camp support comes out I'm looking forward to being able to try this without destroying my Boot Camp installation. When I tried to create a Boot Camp instance of XP with Parallels with 3120 it just didn't work -- Parallels just hung or went into an infinite loop when accessing the Boot Camp partition for the first time. When I upgraded to 3150 and tried again the result was total destruction. I had to completely erase the Boot Camp partition, nothing was possible with it, it was completely trashed.

    Well, it doesn't just affect the boot partition, as I just discovered. Yesterday I ran Parallels compressor on my test installation, which consists of an XP VM on two virtual hard disks: One on the main hard drive for the Windows system files and an additional virtual hard disk on a second physical hard disk as the data drive. Everything seemed to complete correctly, but when I started up again this morning the virtual data drive was gone. Poof. Completely gone, with all its data. Not a trace of it anywhere to be found...

    This doesn't exactly fill me with great waves of confidence... :mad:
     
  5. Khoji

    Khoji Member

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    77
    Follow-up on the Compressor issue:
    I just realized that it wasn't Compressor that was the culprit. I was using the same virtual data drive for more than one virtual machine and I had deleted an old virtual machine that I had imported from VMWare and configured to access the same virtual data drive without thinking about the consequences for the virtual data drive. That probably also deleted the virtual data drive. Sorry for the false alarm...:rolleyes:
     
  6. dkp

    dkp Forum Maven

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    1,367
    Sometimes I think this stuff is like a Rubix cube or a Sudoku puzzle - It's like having to keep a lot of plates spinning (http://www.jugglingworld.biz/shop/products_spinning_plates.html) to keep this stuff going :)
     
  7. Khoji

    Khoji Member

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    77
    I agree. It would be nice to have more transparent facilities for allowing multiple VMs to access the same virtual data drive. For example, it would already be a big help if the Erase VM function would pop up a prompt asking you if you also want to erase the additional data drive when you erase the VM.
     
  8. palter

    palter Hunter

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    243
    When I've used Delete VM, it displays a wizard which lists exactly what it's going to do. You can then uncheck the items you don't want deleted. Did this change in the beta? (I'm running 1970 as I don't use beta software in production.)
     
  9. Purplish

    Purplish Forum Maven

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    521
    On your original concern about data security:

    I run quicken. I back up the entire VM (as well as my entire MAC hard drive) every night.

    If I do a lot of work in Quicken, and I want additional security beyond the nightly backup, I back up Quicken to the shared folder. This way, if anything happened to the VM before the backup, I can still access the latest Quicken data files through the Mac OSX.

    So if you have particularly valuable files, put a copy in the shared folder.
     
  10. PubGuy

    PubGuy Hunter

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    119
    Personally, I don't store my data files within a VM, I use the Shared Folders an map a specific Mac folder as my data folder. That way it is safely backed up with my other Mac data and can be accessed by multiple VM's. I only use the local (inside VM) folders for temporary or transient storage, the good stuff is saved to the Mac's Shared Folders. Never had a problem doing it this way. :D
     

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