Results 1 to 6 of 6

Thread: Boot off USB 2.0 on an Intel iMac

  1. #1
    Join Date
    Oct 2010
    Beans
    17
    Distro
    Ubuntu 10.10 Maverick Meerkat

    Boot off USB 2.0 on an Intel iMac

    I have an intel iMac that will not boot off of a USB drive with Ubuntu installed (my PC netbook boots off the usb drive fine) or my external hard drive with Ubuntu installed. I heard somewhere that you cannot boot off of usb on iMacs even if they are Intel, but a Genius bar guy told me diffferent. Then why won't it work for me, and how can I make it? Thanks.

  2. #2
    Join Date
    Apr 2005
    Location
    Finland/UK
    Beans
    Hidden!
    Distro
    Ubuntu 14.10 Utopic Unicorn

    Re: Boot off USB 2.0 on an Intel iMac

    Yes, you can. Just plug in the USB drive and hold down the option key while turning on the iMac.

    But there's a small catch here; Macs only boot from drives with a GUID partition table. And your drive most likely has a MBR partition table instead...

    edit: I'm not sure if the Disc Utility in Ubuntu is able to create GUID partition table for you, but since you have a Mac around you can use it's Disc Management tool to do this. Of course doing it will destroy all data on the drive, so you'll need to reinstall Ubuntu to the drive afterwards. And you'll probably have troubles booting the drive on other computers than Macs...
    Last edited by mcduck; December 20th, 2010 at 09:22 AM.

  3. #3
    Join Date
    Apr 2005
    Location
    Finland/UK
    Beans
    Hidden!
    Distro
    Ubuntu 14.10 Utopic Unicorn

    Re: Boot off USB 2.0 on an Intel iMac

    ...actually the article is about older PowerPC macs...

    It's much simpler on Intel macs, as long as you prepare the drive by paritioning it using GPT. After that you can, for example, use the Startup Disc Creator that comes included in Ubuntu and everything should work fine.

  4. #4
    Join Date
    Oct 2010
    Beans
    17
    Distro
    Ubuntu 10.10 Maverick Meerkat

    Re: Boot off USB 2.0 on an Intel iMac

    Quote Originally Posted by mcduck View Post
    Yes, you can. Just plug in the USB drive and hold down the option key while turning on the iMac.

    But there's a small catch here; Macs only boot from drives with a GUID partition table. And your drive most likely has a MBR partition table instead...

    edit: I'm not sure if the Disc Utility in Ubuntu is able to create GUID partition table for you, but since you have a Mac around you can use it's Disc Management tool to do this. Of course doing it will destroy all data on the drive, so you'll need to reinstall Ubuntu to the drive afterwards. And you'll probably have troubles booting the drive on other computers than Macs...
    Thanks. Your GUID partition table only things sounds logical, but won't it switch to MBR when I install Ubuntu on it?

  5. #5
    Join Date
    Apr 2005
    Location
    Finland/UK
    Beans
    Hidden!
    Distro
    Ubuntu 14.10 Utopic Unicorn

    Re: Boot off USB 2.0 on an Intel iMac

    No, it doesn't if you don't completely repartition the drive during the install. (I can't remember if the installer has an option to use GPT instead of MBR, it might actually even have that...)

    Formatting existing partitions or creating new ones will not change the partition table type.

    This thread seems to have more discussion about using GPT with Ubuntu 10.10: http://ubuntuforums.org/showthread.php?t=1622938

  6. #6
    Join Date
    Oct 2010
    Beans
    17
    Distro
    Ubuntu 10.10 Maverick Meerkat

    Re: Boot off USB 2.0 on an Intel iMac

    Thanks for your help. It wouldnt' boot still, but when I went back int oMac it even thought that the Linux partition was Boto Camp. It still wouldn't boot though...

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •