External drive partioning for OS X and bootcamp

Discussion in 'Windows, Linux & Others on the Mac' started by Aidonia, Apr 9, 2015.

  1. Aidonia macrumors newbie

    Joined:
    Apr 8, 2015
    #1
    I have a 2013 nMP. It has the basic 256GB internal SSD. I am constantly running out of space so I need to add an external drive on which to store media etc and retain the internal as a basic system drive.
    I also wish to install bootcamp (running Windows 8) on an external drive.

    My question is this:

    Can I partition my G Raid 4TB thunderbolt drive (Raid 0) to use as both extra storage for os X, and the other partion as my bootcamp drive?
    What about formatting of the drive? Would it need to be MS-DOS or ExFAT for both operating systems to read the same raid array?

    Or would I be better off reformatting each of the 2 TB disks as entirely separate drives for each operating system?

    Any thoughts on the way to go and potential problems appreciated!


    *I posted this in the Peripherals forum originally but is probably better suited here. Sorry mods, feel free to remove the first post. Thanks
     
  2. yjchua95 macrumors 604

    Joined:
    Apr 23, 2011
    Location:
    GVA, KUL, MEL (current), ZQN
    #2
    For access between OS X and Windows, use ExFAT.

    You can run Windows off an external drive, but I'm not sure whether it can be done via an RAID array.

    Connect external drive to Windows VM. You must have a Windows VM in VMware/Parallels/VBox, or a Windows PC. Any existing Windows environment will do.

    What you need:
    install.wim file (obtain this from your Windows ISO)

    Open elevated cmd.exe (run as admin)

    Note: All commands aren't case sensitive, including pathway to files.

    Type diskpart
    Type list disk
    Take note of the disk you want to select
    Type select disk 1 (if your disk is Disk 1)
    Type clean
    Type convert gpt (stop at this point if you're using a drive with a Thunderbolt port)
    Type create partition EFI size=100 (skip if installing in BIOS-CSM)
    Type format quick fs=fat32 label=EFI (skip if installing in BIOS-CSM)
    Type assign letter=S (skip if installing in BIOS-CSM)
    Type create partition primary
    Type format fs=ntfs quick label=W2G (or any other name you wish for label)
    Type assign letter=E
    Type exit

    Open up File Explorer. In your C drive, create a new folder named WIN2GO.
    Put the install.wim file in this folder

    Back in cmd.exe:
    Type dism /apply-image /imagefile:C:\WIN2GO\install.wim /index:1 /applydir:E:\ (this process will take quite a while)
    Type E:\Windows\System32\bcdboot E:\Windows /s S: /f UEFI (use this one for UEFI installation)
    Type E:\Windows\System32\bcdboot E:\Windows /s E: /f ALL (use this one for BIOS-CSM installation)

    Restart your entire Mac. After the chime, hold down Option and when prompted to select your boot drive, select EFI Boot (or whatever else that comes up for a BIOS-CSM installation).

    Proceed installation normally.

    After installation, install Boot Camp drivers. Feel free to trash the VM once you're done too.

    For best results, use USB 3/Thunderbolt. If you don't have USB 3, use Thunderbolt. If you have neither, stick back to the internal drive :)

    Don’t use a USB stick.

    Note: This method involves reformatting the entire external drive.

    For Thunderbolt drives, just boot from the Windows USB installer and install directly onto the TB drive. Windows sees TB drives as an internal PCIe connection. However, you must format the TB drive as GPT first.

    CAUTION: Windows can only be installed in UEFI flawlessly on Haswell Macs and later. Ivy Bridge and earlier Macs can only run Windows in BIOS-CSM flawlessly. Attempts to boot a UEFI installation of Windows on an Ivy Bridge or earlier Mac will result in driver issues.

    UEFI-compatible Macs:
    MacBook Air (mid-2013 and later)
    iMac (late-2013 and later)
    Retina MacBook Pro (late-2013 and later)
    Mac Pro (trashcan shape)
    Mac Mini (late-2014 and later)

    Non-retina MBPs are not UEFI compatible.

    WinToUSB basically does the same thing, but doesn’t always work because WinToUSB doesn’t really take into account between BIOS-CSM and UEFI Macs; it only uses one method for all (which may result in boot failures and other problems).
     

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