osx - OS X Lion thinks Windows UDF-formatted external drive as exFAT and tells that the drive is invalid

03
2014-01
  • can poyrazoğlu

    I've recently bought a Mac, and I want to share my Seagate FreeAgent 1.5 TB external hard drive with both my Mac and my PC. I've searched and found that exFAT or UDF is the way to go to have read/write access on both platforms. I've gone with UDF (I've read that exFAT is better for flash drives and it is also proprietary hence no official linux support -- if I ever need it just in case) and when I plug it in the Windows (where I formatted it as UDF) it works fine. When I plug it into my Mac, it says the drive can't be read and offers me to format it or eject it. When I go to disk utility, it shows the drive formatted as exFat (no I'm sure it is not. It is UDF, I formatted it from the command line with UDF option and it shows as "UDF" under Windows). I try to verify/repair the disk and here is the screenshot of what I get:

    error

    What could be the cause of the problem and how can I solve it?

    • Answers
  • Aaron McMillin

    I'm working on this right now. The command line tools are there, but I can't figure out how to automount a UDF drive.

    sudo mkdir /DriveName  # Don't put in /Volumes, so we don't interfere with the automounter
sudo mount /dev/disk2s1 /DriveName

    • Related Question

    filesystems - Which file system to use for a large (1 TB) external hard drive?
  • romkyns

    I've got a 1 TB hard disk drive which is currently formatted as NTFS. I've recently learned about exFAT. I'm connecting this drive via USB. Which filesystem should I use for this large hard disk drive and why?

    (I know exFAT requires a patch on Windows XP; this is not a concern.)


    • Related Answers
  • Joey

    Since basically you're contemplating NTFS vs. exFAT, easy support for other operating systems doesn't seem to be a concern. I'd suggest staying with NTFS. exFAT is primarily meant for smaller volumes and slower devices where the space and complexity overhead of NTFS is an issue.

    So I wonder what exactly do you plan to gain from formatting that drive with exFAT. It's in most ways inferior to NTFS anyway.

  • Manos Dilaverakis

    I'm pretty sure the "If it aint broken" philosophy is appropriate here. Do you really have a reason to start mucking about with filesystems? It's not as if NTFS has any major problems. Besides NTFS is a well-known filesystem that's been around for a while, whereas exFAT is the new kid on the block. This could cause problems down the line. For example if you were to ever use that disk on a linux system, you'd have far more support for NTFS than exFAT.

  • Merstzik

    I would go for the ntfs too. Probably the least problematical and a quite good filesystem for large drives. If you want to tweak your hard-drive as much as it's possible try reading about formatting with the right blocksize for you.

  • harrymc

    I vote also for NTFS. It's a more developed format with which one can do more. See for example the Everything search engine in http://www.voidtools.com/, one of my most useful utilities.

  • brad

    Mac OS X 10.6.5 now supports the exFAT file system so that would not cause an issue on this drive. However, as has been pointed out many times here and everywhere else I have checked on the web, go with NTFS for large hard drives.

  • Gowtham

    Although I'm not a pro - I would have thought for a large drive like that one you would want to go for exFAT for two reasons.

    Firstly, exFAT allows for files to be up to around 16 EiB in size. NTFS also has file size limits that are larger than any drives that will be around for a long time. FAT32 has a max file size of 4GB - so depending on what kind of files you're going to be storing this would be a point to consider.

    Secondly, exFAT is read and write compatible with OS X 10.6.5 upwards, but writing to NTFS is not supported. You never know - this hard drive might last longer than you having a Windows Computer...

  • MarcusJ

    DO NOT USE EXFAT FOR A HDD.it's ruined mine, it keeps losing files and data, and it's a world of hurt man, you don't wanna mess around with it. seriously. hell, I'd try ReFS before I went back to Exfat.

  • user8095

    Do you have any Macs around? Plan on getting a Mac? If so, you may want to use FAT.

    Your best bet may be to create TWO partitions, one FAT and one NTFS. Check out EASEUS Partition Master Home Edition (Free): http://www.partition-tool.com/personal.htm