Do I need an empty external HD for a Time Machine backup?

Discussion in 'Mac Apps and Mac App Store' started by Mershy, Oct 16, 2014.

  1. Mershy macrumors newbie

    Mar 8, 2013
    I've got an external hard drive which is 500GB, however it has other files stored on it. If I want to use it as a Time Machine backup drive, do I need to keep it empty, or will it just create a folder called "Time Machine backup" etc...

    I've got plenty of space for the backups, so that is not a problem.

  2. Nam Pla macrumors member

    Jun 7, 2009
    I have the same question and hope someone can answer.

    My old external drive I was using for TM went bad. Unfixable, as I've tried to restore it. My other external drive has my iTunes music on it, but it is big enough (1 tb) to handle both functions I believe.

    My question is would I be able to create a separate 'Backup' folder and use only that folder as my TM backup drive, without otherwise overwriting my iTunes music folder? Or does TM require its own clean drive with nothing else on it?

    I'm looking to upgrade to Yosemite (I had passed on Mavericks) and need to backup first.

    Thx for any help!
  3. Joker99x macrumors newbie

    Oct 18, 2014
    I believe you would need to format it for it to be compatible with Time Machine. You may be able to partition it for use with storage as well.
  4. glenthompson macrumors 68000


    Apr 27, 2011
    Where do you plan to backup those files stored on the hard drive? All drives fail so if your backup drive fails, you lose both the files and the backup. Better to have multiple backup drives and rotate backups. Keep your data and backups separate. Hard drives are cheap compared to the cost of having to reconstruct my data.
  5. Alimar macrumors 6502a


    Sep 17, 2014
    New York State
    I back up to dedicated drives, and drives with other files on them using Time Machine. TM works both ways, as long as the drive is compatible. If the drive appears in the selection list within TM, then it will work. Make sure your destination disk is equal to or larger than the source disk. Optimum results will happen when your backup drive is dedicated to TM only. Errors occur occasionally when TM is trying to backup to a disk that is being read by another task.
  6. Nam Pla macrumors member

    Jun 7, 2009
    Will partitioning the drive reformat it and erase everything that's on it? Or can I partition and still leave my iTunes music folder intact?
  7. Weaselboy Moderator


    Staff Member

    Jan 23, 2005
    If the drive is already in the Mac HFS+ format, you can just shrink the existing music partition then add a new partition below that. Give this a look.

    If the drive is not now in the Mac format you will need to move the music off then create the two partitions and move the music back.

    The second partition can then be used for your Time Machine backups.

    Of course, this means your music on that same drive is not backed up anywhere.

Share This Page