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Q: Cloning with Disk Utility (10.11), how reliable is it? Can you trust its verify?

I cloned a 4TB with some bad sectors (according to DriveDx) to a new 4TB. The drive verified successfully. Can I trust the contents of the new drive? If the drive verified does that mean that the bad sectors were readable, or just that Disk Utility copied corrupted data "successfully".

 

Another thing, when I booted up the computer, Time Machine didn't recognise that the the new drive was a clone of the previous one and deleted all backups of the previous drive (nice one Time Machine)...so now, the only two copies of my entire life's work are these two 4TBs...

iMac (27-inch Mid 2011), OS X El Capitan (10.11.5), 16GB

Posted on Sep 2, 2016 6:53 AM

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Q: Cloning with Disk Utility (10.11), how reliable is it? Can you trust its verify?

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  • by Luis Sequeira1,

    Luis Sequeira1 Luis Sequeira1 Sep 2, 2016 7:11 AM in response to simcc
    Level 6 (12,211 points)
    Mac OS X
    Sep 2, 2016 7:11 AM in response to simcc

    Check this for how to move your Time Machine backup to another disk:

     

    Time Machine: How to transfer backups from a current backup drive to a new backup drive - Apple Support

  • by simcc,

    simcc simcc Sep 2, 2016 7:40 AM in response to Luis Sequeira1
    Level 1 (14 points)
    Mac OS X
    Sep 2, 2016 7:40 AM in response to Luis Sequeira1

    Thanks, but this is not what I'm asking.

     

    Part one: I cloned a disk that I use to store my files on (i.e. not the drive that has Time Machine on it, Time Machine resides on a separate disk), onto a new drive via Disk Utility, as it (the old drive) had developed bad sectors. Will the new drive have OK data on it, or will the files that were located on bad sectors (on the old drive) be corrupt (on the new drive)?

     

    Part two: that disk was being backed up by Time Machine. When I booted up with the new disk (the clone), Time Machine figured it should delete all previous backups to make space to backup the new drive...why did it do this, it was a clone.

  • by Boyd Porter,Helpful

    Boyd Porter Boyd Porter Sep 3, 2016 4:19 AM in response to simcc
    Level 4 (1,002 points)
    Sep 3, 2016 4:19 AM in response to simcc

    Start here to understand how Time Machine works. http://pondini.org/TM/Works.html

    and here to get an idea of why the backups were deleted: http://pondini.org/TM/E1.html

     

    Have a nice day.

  • by simcc,

    simcc simcc Sep 2, 2016 11:35 AM in response to Boyd Porter
    Level 1 (14 points)
    Mac OS X
    Sep 2, 2016 11:35 AM in response to Boyd Porter

    Hi, thanks.

     

    The first part of my question is the more important one...I probably shouldn't have mentioned Time Machine.

     

    Thanks for the links, but they fail to open? I have a fairly good idea of how Time Machine works. The second part, regarding Time Machine: my guess is that for whatever reason Time Machine decided that the cloned disk was not identical, and so deleted all backups in order to make space for a whole new backup, which is what it did...this would not be that big of a deal, except that I'm worried that the cloned disk contains corrupted files, due to the development of bad blocks on the original disk...

     

    I actually tried to set up the new disk from the Time Machine backup, it failed a few times, possibly because we're talking 2.6TB of data...also it was a few weeks out of date...anyway, I assumed I would still have the Time Machine backup and I was then going to do a checksum between it and the new cloned drive, for any files that were common to both...

  • by Boyd Porter,Helpful

    Boyd Porter Boyd Porter Sep 3, 2016 4:19 AM in response to simcc
    Level 4 (1,002 points)
    Sep 3, 2016 4:19 AM in response to simcc

    Yes, cloning with Disk Utility is safe. I use it periodically when I install a new drive. I clone to an external drive and then clone back to the internal. If in doubt, boot from your clone, and open your data files.

     

    Type or copy and paste the address of the second link in to the address bar of your browser. Both of them open for me when I click on them.

     

    Have a nice day.

  • by simcc,

    simcc simcc Sep 3, 2016 4:20 AM in response to Boyd Porter
    Level 1 (14 points)
    Mac OS X
    Sep 3, 2016 4:20 AM in response to Boyd Porter

    Thanks, I would trust it in general...however, I'm unsure how its verify deals with bad-blocks and corrupt data...this is the primary issue in my question.

     

    Got them to work...good info on Time Machine there...Time Machine Buddy is cool, glad to know about this, was going to ditch Time Machine...now on the fence...I like its integration/features, though I think CCC is safer.