Does Carbon Copy Cloner use the entire backup drive?

Discussion in 'Mac Basics and Help' started by hajime, Sep 20, 2016.

  1. hajime macrumors 603

    Jul 23, 2007
    Hello, as far as I recall, even the external backup drive is larger than the internal MBP drive, using SuperDuper would make the larger drive to clone the smaller internal drive only. People could not copy extra files to the external drive. What about CCC? Supposing I have a 2T external drive and a 1T SSD on my MBP, after using CCC, can I copy other files to the 2T drive?
  2. Fishrrman macrumors P6


    Feb 20, 2009
    "Supposing I have a 2T external drive and a 1T SSD on my MBP, after using CCC, can I copy other files to the 2T drive?"

    The size of the CCC backup will equal that of the source that is being backed up.
    Generally, you DO NOT WANT TO copy other files to that backup. You want it to be "a clone" of the source -- nothing more, nothing less.

    If your source volume is 1tb, and your backup volume is 2tb, my suggestion is this:

    PARTITION the backup drive into two equally-sized partitions.

    Use the FIRST partition for your CCC cloned backup.
    Use the second partition for general file storage.

    This will work very well. The only difference is when you connect the 2tb drive, you will see TWO volumes on the desktop (one representing the CCC cloned backup, and the other representing your "additional storage" drive.
    Be sure that you give each volume an appropriate, easily-reconizable name.

    Bear in mind that if you do things this way, the second partition IS NOT "backed up".
    If the files on that volume are important to you, they must be backed up TO ANOTHER DRIVE, as well.
  3. dwig macrumors 6502a

    Jan 4, 2015
    Key West FL
    As Fishrrman correctly pointed out, you need to partition the target drive.

    It is never the size of the drive that matters. It is, instead, the size of the partition that matters. The drive size merely sets the maximum total size of all partitiions, whether one partition or many. You can have many, many partitions on the drive if you want. Each partition will mount as a separate volume and pointing CCC to one volume will not alter the others.
  4. BrianBaughn macrumors 603


    Feb 13, 2011
    Baltimore, Maryland
    The default behavior for a CCC clone is to move files deleted from the original drive (since the last backup) into subfolders in a "_CCC SafetyNet" folder. So, if you want this sort of behavior you need enough space on the clone to hold it.
  5. awair macrumors regular

    Sep 6, 2011
    You have two options:
    1) CCC will use the entire drive in a single partition. This will be bootable, and you can add files/folders (but then it is no longer a true clone.)
    2) Create an equal sized partition for the clone and use the remainder of the space for another partition, for any other purpose (including Time Machine, Archive etc).

    Both are valid options - just don't rely on a single drive for two different types of backup.
  6. hajime thread starter macrumors 603

    Jul 23, 2007
    Thanks. Given that the SSD in my MBP is 1T, I should create a partition of 1T in the backup drive to backup my laptop. Am I right?
  7. organicCPU macrumors 6502a


    Aug 8, 2016
    The optimum size is the maximum amount of data that will be on your internal drive. For making a bootable clone 1TB (partition) fits for everything of a 1TB internal drive. CCC doesn't clone unneeded files like swapfiles and memory snapshots. That's why it's not a must to have the exact amount of space on the external drive even for almost filled internal drives.
    If you just backup files, you can do this at any place on the drive, preferably in a subfolder. If you keep copies of changed versions, there will be a _CCC Archive-folder on the same directory-level as your subfolder. Outside this subfolder and the Archive-folder you can keep whatever files you like. As long as there is enough space, you can create multiple subfolders for multiple kinds of backups (different machines or purposes).
  8. hajime thread starter macrumors 603

    Jul 23, 2007
    Thanks all for the info.

    Many years ago, users used Super Duper which was free. How is Super Duper compared with CCC these days?

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8 September 20, 2016