failed attempt to backup hard drive. help please.

Discussion in 'macOS' started by macuser55, Apr 19, 2009.

  1. macuser55 macrumors newbie

    Mar 16, 2009
    i want to re-install my OS from scratch. so i used SuperDuper to backup my HD onto my 1TB My Book but something went wrong. this is my first time trying this so i have no clue why it didn't work. can anyone help me understand/fix this? here's some screenshots..


  2. macuser55 thread starter macrumors newbie

    Mar 16, 2009
    i normally wouldn't bump but i kinda need help by 10:00 pm EST. :confused:
  3. Jethryn Freyman macrumors 68020

    Jethryn Freyman

    Aug 9, 2007
    Is the hard disk formatted correctly? (HFS+).
  4. ewilson6 macrumors 6502

    Nov 30, 2006
    no its formatted for Windows. read the log!

  5. misterredman macrumors 6502a


    Oct 3, 2007
  6. Ploki macrumors 68040

    Jan 21, 2008
    why not use disk utility which clones block by block?
  7. gr8tfly macrumors 603


    Oct 29, 2006
    ~119W 34N

    I've been using Disk Utility's Restore literally for years. Block copy is also faster than file copy by a longshot.

    To enable block copy in Disk Utility, check the "erase destination" option. This also requires you boot off a 3rd volume (the Leopard install DVD is easy, but any other bootable (up-to-date is best) volume with Disk Utility will work). The reason is block-copy needs to unmount both the source and destination volumes.

    Many years ago I used Carbon Copy Cloner, but it was slow and problematic (perhaps that's been fixed, but I lost trust in the app). I haven't looked closly at SuperDuper - it looks like it does go through a sort of "pre-flight" for you by checking permissions and verifying the source volume. That's good, and necessary, but can also easily be done right in Disk Utility. I know a lot of members here use SuperDuper, but I personally don't see the need.

    Here's a quick run-down on using Disk Utility: Check permissions while booted on the source volume, then boot to the "3rd" volume. Run Disk Utility, verify the source volume, then prepare the destination - GUID partition map, HFS+ journaled. Restore (check "erase destination"). Wait a bit (depends on interface type and volume size). Enjoy clone.

    A block copy won't have any issues with file permissions or broken links, which looks to be the show stopper in the OP's backup attempt. Of course, if there is a problem like a broken link, it will be dutifully cloned.

    One more thought: since the block copy erases the destination, it's good to setup a partition on the destination drive. For instance: Source drive is 160GB. You wouldn't want to erase the entire 1TB volume every time you wanted to clone. It's probably a good idea, though, to make the partition large enough to handle a future, larger drive (like a 320, for instance). Keep in mind the destination needs to be the same size or larger than the source.

    (note: in the "prepare" part, above, once the destination drive has been partitioned with the GUID map, it doesn't need to be done again - in fact, doing so will erase ALL the partitions on the drive (that is, if you change the partition map type). You can adjust the size of and add/subtract partitions dynamically, but you can't change the partition map without affecting the entire drive.)

    Some background info:
    Disk Utility is a front end for ASR (Apple Software Restore)

    from the ASR man page:

    Apple Software Restore got its start as a field service restoration tool
    used to reconfigure computers' software to 'factory' state. It later
    became a more general software restore mechanism and software installa-
    tion helper application for various Apple computer products. ASR has
    been used in manufacturing processes and in shipping computers' System
    Software Installers.

    For Mac OS X, asr was rewritten as a command line tool for manufacturing
    and professional customers. asr is the backend for the Mac OS X Software
    Restore application that shipped on Macintosh computers as well as the
    Scan and Restore functionality in Disk Utility.
  8. macuser55 thread starter macrumors newbie

    Mar 16, 2009
    i've read that disk utility erases all data on the external HD during the backup process. is that correct? i need to keep all data on my external HD.
  9. gr8tfly macrumors 603


    Oct 29, 2006
    ~119W 34N
    It does erase a volume under the following conditions: it needs to be repartitioned (or cannot do dynamic repartitioning); The partition map needs to be changed [to GUID, for instance]; or when doing a Restore using the "erase destination" option - which is required when doing block-copy (and, in fact enables block-copy). It will only erase the destination volume, not any other volumes/partitions on the drive. Disk Utility is very clear in its messages about what gets left along and what will get erased.

    If the data isn't related to the cloned source drive, you could create a partition a bit larger than the source - then use only that partition for your clone.

    It's important to use "block-copy", as it greatly improves the copy speed, and also exactly mirrors your source. Unfortunately, it needs to erase the destination (target) partition - but, only that one partition, not the entire device.

    That's why I mentioned the part about not wanting to erase the entire 1TB target drive (the MyBook). I was making an assumption about the source drive/partition being much smaller than that.

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