A basic backup-imaging question:

Discussion in 'backup, imaging & disk mgmt' started by razorboy, Mar 23, 2015.

  1. razorboy

    razorboy Registered Member

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    When using a programme such as Macrium or its competitors, does the backup function back up to the image, so that the (say) daily data files back up into the copy in the same place as they exist in the working drive, so that if your working drive fries itself two minutes after backing up, you can just replace the drive and carry on, all backed up and all?

    Thank you.
     
  2. TheRollbackFrog

    TheRollbackFrog Registered Member

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    RazorBoy... what you appear to be describing is a CLONE type of operation. Not all imaging programs do this type of backup imaging, Macrium does.

    A normal simple imaging operation does not do as you describe. It protects your intended volume by backing up a compressed copy of the drive (not only files but also important parts of the physical volume that are required to reassemble it and make it BOOTable) and then all follow-on changes as time moves on. It does this to a physically different volume than the one being protected. If the protected drive goes bad, you replace the bad drive, BOOT into a BOOTable CD/DVD/UFD and use the imaging system contained on that BOOTable device to restore the compressed saved images to the replacement drive. Following the restoration procedure, the replacement drive will be as the original drive was... all your files and operating system returned as it was.

    Your description is of a CLONing operation. As the backup is performed, the most recent changes are placed in exactly the same place on the backup drive as they are in the protected drive. This allows you, in time of failure, to just replace the drives and BOOT right back up. Not all imaging programs do this so be careful when looking into such capability.

    In reality, the only practical difference between these two methods is time... the time to do the restoration function. This, of course, differs depending on what type of devices are being used.
     
  3. Robin A.

    Robin A. Registered Member

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    If what you mean is a "continuous backup" operation, it can be implemented using a RAID 1 configuration. http://en.wikipedia.org/wiki/RAID.
     
  4. razorboy

    razorboy Registered Member

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    Thanks very much for those replies. I think that puts me in the right direction. (I'm reading on RAID...... my head hurts.) I should add that my new box is a digital audio workstation, and there will be at least two working hard drives: one for the data, and one for the OS, recording software, and all the normal stuff. Even a third working drive is possible, but not likely as I envision it now. I'm taking the components to the builder/engineer person today. Of course, answer breed more questions:
    (1) Does the clone>>>backup system have to be RAID, or is RAID just one approach?
    (2) Does Macrium use RAID?
    (3) From what I see here using the board's search function, Macrium seems to be the local favourite. Are there competitors to consider?

    What I would do, BTW, is make one or more clone and back up to them maybe one to three times daily, something like that.

    Thanks again.
     
  5. TheRollbackFrog

    TheRollbackFrog Registered Member

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    RazorBoy, RAID is a hardware approach to cloning a disk in real time. It's usually supported by your system's mainboard or an add-in interface that can accomodate RAID. Many modern mainboards support RAID as an option in their BiOS.

    Software cloning also requires a 2nd disk, same as RAID, but is usually done "periodically" based on how often you want the volume "in sync" with your master disk. It does not require an active RAID configuration.

    The application software doesn't usually see a RAID hardware configuration... to the application it just looks like a single disk, managed by the hardware between the app and the RAID array of disks.
     
  6. razorboy

    razorboy Registered Member

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    To me, having read the above collected wisdoms, that seems the way to go. Clone, back up to clone daily, one or two copies.
     
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