looking for good data recovery program

Discussion in 'Mac Apps and Mac App Store' started by phuong, Oct 23, 2007.

  1. phuong macrumors 6502a

    Joined:
    Aug 16, 2006
    #1
    i posted this in another thread here but got no answer. i guess it's better posted here. can some mod/admin help me delete that thread plz thanks.
    ======================

    My Drobo thingy arrived today. my brother received it and installed it.
    and out of curiosity, he took one of the hard drives out of my MP and inserted it into the drobo. and he restarted the computer... you know, the regular steps.

    well, there's a BIG "but" here. there's a sticker saying that, whenever you insert a hard-drive into Drobo, it erases it right away. so, my entire full 500GB of movies and musics and stuffs went "puff" now. my bro says when the OSX asked to initiate the drive, he freaked out and canceled every thing the computer asked him to do. but still, OSX won't recognize the disk now unless we erase it and initiate it (which means data will really be gone)

    i only have a small hope that Drobo only wrote some initial information onto the drive and did not format it entirely, so technically there should be a way to recover those data.

    anybody got any idea? i suppose there are programs that do this stuffs. on the Windows side i got Recovery which is excellent. but this drive is Mac data so that program won't help.
     
  2. Makosuke macrumors 603

    Joined:
    Aug 15, 2001
    Location:
    The Cool Part of CA, USA
    #2
    DataRescue II:

    http://www.prosofteng.com/products/data_rescue.php

    ...that's your best (pretty much only other than sending it to a recovery place for a LOT of money) option for an initalized disk like that.

    You can try before you pay and see how many files it can see--you've got nothing to lose, anyway.
     
  3. CanadaRAM macrumors G5

    CanadaRAM

    Joined:
    Oct 11, 2004
    Location:
    On the Left Coast - Victoria BC Canada
    #3
    But I think you;re hoovered. THe enclosure would have reformatted the drive with its own filesystem, which is why your Mac does not recognize a volume on the drive any more.
     
  4. phuong thread starter macrumors 6502a

    Joined:
    Aug 16, 2006
    #4
    formatting a whole 500GB would have taken hours, so that's not possible. OSX recognized the volumn - it just can't access it since the directory structure is lost.
    i tried Data Rescue II, the quick scan shows me mostly my mp3 files - which are generally 5MB each. it doesn't show me any movie files, however, so i'm doing a thorough scan now - but i have to wait for 2 hours before seeing the results.

    in the mean time, i see that on the Apple site, they mention Disk Warrior (http://docs.info.apple.com/article.html?artnum=2686) Does anyone got any experience with it?
     
  5. CanadaRAM macrumors G5

    CanadaRAM

    Joined:
    Oct 11, 2004
    Location:
    On the Left Coast - Victoria BC Canada
    #5
    DiskWarrior repairs directory structures and is very good at it.
    It is not, however, a file recovery program.

    And I beg to differ -- OSX may have recognized the *drive* but it did not recognize a HFS volume, which is why it offered to initialize it for you.
     
  6. phuong thread starter macrumors 6502a

    Joined:
    Aug 16, 2006
    #6
    i don't quite get what you mean.
    so, if DiskWarrior can restore my directory structure, wouldn't it be easier that way? since my data wasn't really deleted. they're still there, just not accessible.

    (i think i was unclear on this point. the disk wasn't initialized, since as soon as my bro saw OSX ask him to do that, he canceled it and shut down the computer - at least that's what he says - which i think is true cause DataRescue sees quite a lot of files, including files that i deleted ages ago.)

    still, i'm still not clear what the diffence between these two programs are. can you elaborate? and which one should i use?
     
  7. Makosuke macrumors 603

    Joined:
    Aug 15, 2001
    Location:
    The Cool Part of CA, USA
    #7
    No.

    I think you may not be picturing exactly what happened here. I'm vastly oversimplifying, but basically what you've got on a drive is a little chunk of data that says "This is XXX type of partition" then a little chunk of data that says "Each file is stored here", and finally a whole pile of data that is the actual files.

    When you're thinking "format", you're thinking of what was an old-style "Low-level" format; that is, going over every block on the disk and initializing it.

    What most formatting apps do at this point is just assume the drive is empty and write whatever is necessary for the first two types of data. This will overwrite some (or all) of what partition and directory information existed before and replace it with new stuff. This will cause the drive to look as if it's whatever the new format is, and as data is added to it it will overwrite whatever data was in that space previously.

    So what happened in your case is that the box basically slapped new partition information on the drive. This causes the drive to look totally unreadable to the Mac (since it's not a partition scheme the MacOS recognizes), and no doubt damaged at least some of the partition/directory information that was there before.

    What Disk Warrior does is look at the existing directory information, clean it up, and replace it with the new, clean copy. Since your disk effectively HAS no directory information now, Disk Warrior has nothing to start with, and will likely be useless.

    This is where Data Rescue II comes in--what it does is comb through all the raw data on the disk trying to find bits of remaining directory information or individual files. This means that it will sometimes find files that were deleted (meaning that the pointer to them was deleted, but the data remained on disk, which is what happens when you empty the trash non-securely), and can also recover data from a reformatted disk like yours.

    Had you done a full wipe, where the drive had, say, all 0s written to its surface, then there'd be nothing. As is, Data Rescue II is looking for anything that appears to have formerly been a file, so is finding a lot of stuff.

    Depending on how much of the old directory information was wiped when the drive was reformatted, Data Rescue II may find quite a bit of what was there before. Regardless, though, it's your only option other than an expensive data recovery house--Disk Warrior is a waste of money for your issue.
     

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