External HDD Partition Question

Discussion in 'Mac Accessories' started by MattieD, May 1, 2013.

  1. MattieD macrumors newbie

    Jun 19, 2012
    I have an External HDD that I want to use as a Time Machine backup and a mass storage device that is usable with Mac and PC.

    I partitioned the 2TB drive into a 500GB Time Machine volume with the Mac OS extended journal file system and a 1.5TB volume with the exFat file system

    My friend who has been a programmer for many moons seems to think that using the 2 different file systems on the same HDD will cause problems or increase the chances of corrupting the disk. Does anyone know if these concerns hold any truth?

    Wasn't sure where to post this but my external HDD is a peripheral.
  2. FreakinEurekan macrumors 68040


    Sep 8, 2011
    Eureka Springs, Arkansas
    I've never heard of any problems doing that, I have a drive set up the same (except NTFS instead of exFAT on the 2nd partition).
  3. Weaselboy Moderator


    Staff Member

    Jan 23, 2005
    Ditto Matt. I have never heard of this causing a problem.
  4. ColdCase macrumors 68030

    Feb 10, 2008
    Not an issue, I don't think the PC will mess with the TM volume just for spite :)
  5. fortysomegeek macrumors regular

    Oct 9, 2012
    Here is my experience. I have over 40. yes, FORTY external drives of various sizes 2.5" & 3.5". My current setup are 3 & 4TB. I have a drawer with about 8 blank 4TB ready to be used.

    I've had drives corrupt with dual HFS/exFAT.
    I've had drives corrupt with any form of encryption in a dual partition set-up.

    Never had corruption with HFS/FAT32 up to 2TB.

    Drives over 2TB (e.g. 3 & 4TB) will corrupt due to their blocksize,headers,etc.. The Seagates 4TB that requires drivers for OSX with Thunderbolt, I would only do single partition.

    exFAT in a dual set-up usually involves repairing disk permissions all the time. The corruption is minimal and varies with disks.

    Encrypted HFS (when paired with multiple partitions) always required repair 2/4 times they were mounted.

    I would do 2, 3 partitions. HFS, exFAT, and FAT32 on some drives because I need to mount them on FreeBSD.
    Then again, I hear other people not having problems. I'm an extreme use-case example. I usually format GPT/GUID partition tables.
  6. tengtengvn macrumors member


    Apr 14, 2013
    My ext drive has 2 partitions, HFS+ and NTFS. I've been using it for a long time without issue so far.
  7. MattieD thread starter macrumors newbie

    Jun 19, 2012
    So would a more stable setup be 2 HFS partitions one for time machine and one for mac storage and then a FAT32 for sharing or the occasional need to transfer files?

    I just need this drive to be as stable as possible if it fails I lose all the movies I've encoded over the years for Apple TV as well as family videos. Therefore, if I need to make this drive completely HFS and get another drive to be mac/pc compatible I will
  8. fortysomegeek macrumors regular

    Oct 9, 2012
    That is what I would do. 1 dedicated HFS for time machine. 2nd formatted for exFAT.
  9. Fishrrman macrumors G4


    Feb 20, 2009
    This is my opinion only.

    I would not put anything I valued and depended on, on a "cross-partitioned" drive.

    One or more HFS partitions, yes.

    One or more Windows-type partitions, yes.

    But, "cross-partitioned" (HFS & Windows-type) ?? Nope.

    Again, my opinion only.

    I _would_ suggest that you take the drive that is intended for Time Machine, and also put a second HFS partition on it, and then use that partition for a "cloned backup" with either CarbonCopyCloner or SuperDuper.

    Put the clone partition "first" in the order of things, and the T.M. partition "behind it".

    You will have more options available in a "moment of need". There's nothing that beats having an instantly-bootable second copy of your internal drive, for when run up against that "I can't boot" situation….

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