Advanced hard drive recovery techniques?

Discussion in 'Mac Basics and Help' started by docwisdom, Nov 30, 2009.

  1. docwisdom macrumors newbie


    Feb 8, 2008
    Santa Cruz, CA
    I have a sata hard drive from an 07 iMac. It was the system drive and today I got a filesystem question mark when booting. I have already swapped the drive and have the machine back up & running with a backup from 15 days ago. I would like to now go into this drive and try to recover the more recent data.

    What I have tried:
    Plugging into an external sata interface via usb and it DOES spin up
    macos recognizes it as a 2tb drive but no file system (this is incorrect, it is a 250gb drive)
    disk warrior does not recognize
    spinrite does not recognize
    data rescue 3 doesnt retrieve any information.

    I tried a quick dip in the freezer with only the same results.

    It seems like since it does spin up that I should be able to read something off of it at a low level. Any thoughts?
  2. techound1 macrumors 68000


    Mar 3, 2006
  3. docwisdom thread starter macrumors newbie


    Feb 8, 2008
    Santa Cruz, CA
    sorry, should have covered that in my OP

    no clicking or ticking
    everything spins up and sounds as normal. It does the standard spin up then seek and then the 'this disk needs to be initialized' screen appears on the mac.
  4. trainguy77 macrumors 68040

    Nov 13, 2003
    I am no expert but it sounds to me like an electronic failure. I have heard people switching the board connected to the drive to get them working before.
  5. fluffyx macrumors 6502

    Oct 25, 2007
    The firmware on the board of a drive is highly tailored to the physical platters. Swapping the board will not work.

    If you have a spare hard drive that has a lot of free space, you might download a free trial of Data Rescue 3 and see if it can find your files. If not, is a high-quality, competitively priced data recovery firm.
  6. nanofrog macrumors G4

    May 6, 2008
    It will if the board is identical (same model, same firmware revision). It's one of the techniques used by drive recovery firms.

    You have to be careful with such software though, as it can cause irreparable damage.

    Assuming the data is valuable enough, then a recovery service would make more sense.
  7. Fishrrman macrumors G5


    Feb 20, 2009
    "You have to be careful with such software though, as it can cause irreparable damage"

    Are you stating in this in reference to Data Rescue?
    If so, please explain just -how- DR can "damage" a drive.

    One of the reasons DR needs an external drive to "recover to" is because it purposefully DOES NOT try to "restore" a directory on a "bad" drive. It merely scavenges the drive "as is" to retrieve bits of data, and then re-assembles the data on a second drive.
  8. alent1234 macrumors 603

    Jun 19, 2009
  9. nanofrog macrumors G4

    May 6, 2008
    It was a more general statement, but it still has some merit with DR as well (the quote in the previous post was to a recovery service, but many try some software tool instead/first on their own).

    DR at least loads it's own Kernel, rather than running off the OS on the damaged drive (assuming it's located on the suspect drive).

    But in general, it still has problems:
    1. It can't deal with electronic failures (board is partially or full DOA). Best case, it does nothing. But if the board is partially functional, it can overwrite Partiton Table data. In such cases, you usually get an identical board and replace it (assuming no mechanical damage, the drive will be functional again). They can replace parts on some occasions if they <data recovery service company> don't have a board (really old drive that they ran out of spares).

    2. Mechanical failure conditions: It varies, and at best, you get some garbage/missing files (not enough for ECC to generate a complete, accurate file). Worse case, the heads can drag accros the platters, causing further damage.

    Usually the problems lie with the user. Simple human error, as they've no real idea of what they're doing. Especially with products from the drive maker (not meant for data recovery, but drive recovery). There is a BIG difference. One saves the information, the later is only designed to get the drive operational, and will sacrifice the data to do it (remapping of bad sectors for example).

    Ultimately, the real solution is to have a proper backup. There is no substitution, as data recovery services are NOT cheap. Not by a long shot.
  10. Broncoman13 macrumors newbie

    Dec 20, 2009
    Can you use Time Machine Backups if you re-install the original OS?
  11. trainguy77 macrumors 68040

    Nov 13, 2003
    Yes assuming the Original OS is the one used to make the backups. You can restore the OS and all data using time machine if you want.

Share This Page