Time Machine and backup drives

Discussion in 'Mac OS X Lion (10.7)' started by party, Aug 5, 2012.

  1. party macrumors member

    Jul 21, 2012
    Hong Kong
    I've been lazy since I've switched to using Macs, but I realise I want to upgrade to OS X 10.8. Well to be safe I had to make a backup for the first time.

    I've googled the information I want but they didn't seem to help. I read that I needed to buy backup drives at least 2x the size of my hard disk (which would be 1TB) for future backups. But I questioned: what kind of hard disk should I buy?

    I own an NTFS drive but it has a size of 500GB and 200GB of it is used. I tried to reformat it but I had troubles so I decided to give up and buy a new drive. I think FAT32 would be the best type but I remembered its largest file size being 4GB.

    So I looked through "All My Files" on my Mac, and the largest file was under 4GB. But Time Machine back-ups my whole Mac, so I've been wondering how large the system files would be? If they are all under 4GB I guess it would be best if I buy FAT32.
  2. Weaselboy Moderator


    Staff Member

    Jan 23, 2005
    You will need to format any drive you attached to your machine for Time Machine in the Mac HFS+ format. Plug in the new drive and start Disk Utility app and select the drive then format it in Mac OS X Extended (Journaled).

    Just buy any drive you want. Any USB external drive can be plugged into your Mac and formatted to work. A lot of users like this Western Digital drive.

    You don't really HAVE to have twice the disk space. The reason you are reading that is Time Machine keeps versions of files. So the larger the files you continually work with, the more space you will need for versions.

    For example, I never work with large files like videos. My entire drive has about 60GB of data. Even after months of backups my Time Machine backup is only around 70GB. It just keeps versions of small documents I work with and does not use much space. Now if I did work with say a 3GB video and made changes to it all the time, that gets backed up with each version and could result in my Time Machine backup being much bigger.

    It just depends on how much room you want to leave for older versions of backup.

    That said, the price difference between a 500GB and a 1TB drive is so small it would be wise to go with the larger drive.

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