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Sadida

macrumors newbie
Original poster
Sep 14, 2011
9
0
I have a 2 TB External Hard Drive that I would like to use to back up my files on my MBP because I will be getting a new one. I understand that I can use my external drive as the back up drive through Time Machine. The problem lies with the fact that I would also like to use my external drive for use with Windows computers. What do I need to do? I believe that I would need to format the external drive to FAT32 format and partition it having one partition as a Time Machine backup and one partition for everything else. Is this correct?
 
I have a 2 TB External Hard Drive that I would like to use to back up my files on my MBP because I will be getting a new one. I understand that I can use my external drive as the back up drive through Time Machine. The problem lies with the fact that I would also like to use my external drive for use with Windows computers. What do I need to do? I believe that I would need to format the external drive to FAT32 format and partition it having one partition as a Time Machine backup and one partition for everything else. Is this correct?
FAT32 isn't a great choice, since it has a limit of 4GB per file. TM requires HFS+, and a better choice for sharing with Windows is NTFS or exFat.

Format A Hard Drive Using Disk Utility (which is in your /Applications/Utilities folder)

Choose the appropriate format:

FAT32 (File Allocation Table)
  • Read/Write FAT32 from both native Windows and native Mac OS X.
    [*]Maximum file size: 4GB.
  • Maximum volume size: 2TB
  • You can use this format if you share the drive between Mac OS X and Windows computers and have no files larger than 4GB.
NTFS (Windows NT File System)
  • Read/Write NTFS from native Windows.
  • Read only NTFS from native Mac OS X
    [*]To Read/Write/Format NTFS from Mac OS X, here are some alternatives:
    • For Mac OS X 10.4 or later (32 or 64-bit), install Paragon (approx $20) (Best Choice for Lion)
    • For 32-bit Mac OS X, install NTFS-3G for Mac OS X (free) (does not work in 64-bit mode)
    • For 64-bit Snow Leopard, read this: MacFUSE for 64-bit Snow Leopard
    • Some have reported problems using Tuxera (approx $36).
    • Native NTFS support can be enabled in Snow Leopard and Lion, but is not advisable, due to instability.
  • AirPort Extreme (802.11n) and Time Capsule do not support NTFS
  • Maximum file size: 16 TB
  • Maximum volume size: 256TB
  • You can use this format if you routinely share a drive with multiple Windows systems.
HFS+ (Hierarchical File System, a.k.a. Mac OS Extended (Journaled) Don't use case-sensitive)
exFAT (FAT64)
  • Supported in Mac OS X only in 10.6.5 or later.
  • Not all Windows versions support exFAT. See disadvantages.
  • exFAT (Extended File Allocation Table)
  • AirPort Extreme (802.11n) and Time Capsule do not support exFAT
  • Maximum file size: 16 EiB
  • Maximum volume size: 64 ZiB
  • You can use this format if it is supported by all computers with which you intend to share the drive. See "disadvantages" for details.
 
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So I would be correct except I shouldn't use FAT32 and instead, use one of the formats you recommended?
 
So I would be correct except I shouldn't use FAT32 and instead, use one of the formats you recommended?
Yes. Make one partition HFS+ for your TM backups and make the other either NTFS or exFAT. See the details under each format for more information.
 
Is there a program I could use to easily make these partitions and formats?

Your help is greatly appreciated
 
GGJ is correct and you should probably follow his advice. However, I did it a slightly different way. Under Disk Utility (found in Applications --> Utilities), I simply formatted the drive as exFat and then used TM to create BackUps. TM made its own specific folder where as I made my own folders for other uses of the drive. However, do see that exFat has some disadvantages (as mentioned above by GGJ).
 
Mac 101: Time Machine
Time Machine can’t backup to an external drive that's connected to an AirPort Extreme, Time Capsule, or a drive formatted for Microsoft Windows (NTFS or FAT format). If you select an NTFS or FAT-formatted drive, Time Machine prompts you to reformat the drive. Choose a different drive or reformat the drive in Mac OS Extended (Journaled) format. Because reformatting erases any files on the drive, only do this if you no longer need the files or if you have copies of them on a different drive.

The most common format for a Time Machine backup drive is Mac OS Extended format, but Time Machine also supports Mac OS Extended (Case sensitive, Journaled) and XSan formats.

If the drive is partitioned using the Master Boot Record (MBR) partition type, some partitions may not be available for use with Time Machine. The GUID Partition Table (GPT) or Apple Partition Map (APM) partition types are recommended.
 
I would recommend that when making your partition for use with Windows computers, to use exFAT, since XP/Server 2003, Vista/Server 2008, and 7/Server 2008 R2 are ALL compatible with exFAT, as well as having the ability to transfer those files between Mac OS X (Running Snow Leopard 10.6.5 or newer) and Windows, where as NTFS won't natively allow Mac OS X to write to it.
 
Sharing external hard drive between Windows and Mac, airport extreme

The advice above is correct if you want to divide your hard drive into two parts, one for windows and one for mac. Or create one big Exfat partition that both computers can use. Plug the hard drive directly into your computer to use time machine with exfat.

I was interested in doing something like what you described above, but I wanted to create my backups over my home network using a drive connected to my airport extreme router.

(airport and time machine: ExFAT and NTFS formats aren't supported).

Here is what has worked for me:
Mac
1. Format the Drive on my Mac using disk utility set to "Mac OS Extended with Journaling"
2. Plug that Drive into the USB port on my airport extreme.
3. Set Time Machine to automatically back up my mac on that drive.

Windows:
1. Installed the free program HFSExplorer http://catacombae.org/hfsx.html
to allow Windows 7 to read the Mac partition on that hard drive.
2. Save files manually to that disk or search for a program to create automatic backups.

Windows 7 Home premium now sees my mac drive plugged in to the airport, and to my surprise is able to save files to that drive as well.

Windows backup did not recognize that drive as a valid backup destination, but for now I'm happy enough with the ability to manually save files and share them between either computer.

I'll look for another backup program later to try to automatically backup windows files to the airport drive.
 
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