How do I burn an ISO on a USB drive on Mac OS X?

12
2014-01
  • Jason Marcell

    what's the best way to get an ISO "burned" to a USB stick on a Mac? Restoring using Disk Utility does not work.

    The ISO is ubuntu mini.iso. It is the minimalist install ISO for installing ubuntu. It needs to be bootable on a PC. I am trying to install ubuntu on a PC that has no CD-ROM. The only other computer I have around is a macbook.

  • Answers
  • l0b0

    Directly from the Ubuntu download page (my formatting):

    1. Download the desired file
    2. Open the Terminal (in /Applications/Utilities/ or query Terminal in Spotlight)
    3. Convert the .iso file to .img using the convert option of hdiutil (e.g., hdiutil convert -format UDRW -o ~/path/to/target.img ~/path/to/ubuntu.iso)
    4. Note: OS X tends to put the .dmg ending on the output file automatically. Remove the .dmg extension as necessary, mv ~/path/to/target.img{.dmg,}
    5. Run diskutil list to get the current list of devices
    6. Insert your flash media
    7. Run diskutil list again and determine the device node assigned to your flash media (e.g. /dev/disk2)
    8. Run diskutil unmountDisk /dev/diskN (replace N with the disk number from the last command; in the previous example, N would be 2)
    9. Execute sudo dd if=/path/to/downloaded.img of=/dev/rdiskN bs=1m (replace /path/to/downloaded.img with the path where the image file is located; for example, ./ubuntu.img or ./ubuntu.dmg).
    10. Using /dev/rdisk instead of /dev/disk may be faster.
      • If you see the error dd: Invalid number '1m', you are using GNU dd. Use the same command but replace bs=1m with bs=1M.
      • If you see the error dd: /dev/diskN: Resource busy, make sure the disk is not in use. Start the 'Disk Utility.app' and unmount (don't eject) the drive.
    11. Run diskutil eject /dev/diskN and remove your flash media when the command completes
    12. Restart your Mac and hold down Alt while the Mac is restarting to choose the USB stick

    Note: On newer Macs you might have to install an EFI boot manager to boot from USB.

  • slhck

    I had a very similar problem that none of these answered.

    It's worth checking out UNetbootin. It will create a bootable USB disk on a Mac for a PC.

  • Chealion
    1. Ensure the USB Key is properly formatted (Master Boot Record, FAT32 - if necessary NTFS using NTFS-3G)
    2. You can try using the Restore feature in Disk Utility by clicking on the USB key's volume, then clicking on the Restore tab and choosing the ISO to restore onto it.
    3. If step 2 fails, you can do this manually by running ditto or cp -r; eg. ditto /Volumes/NAME_OF_MOUNTED_ISO /Volumes/NAME_OF_USB_KEY or cp -r /Volumes/NAME_OF_MOUNTED_ISO /Volumes/NAME_OF_USB_KEY to manually copy all the files (including hidden ones)
  • Per Wiklander

    I've user SuperDuper for this task before. It does the job and not much else. Like a good program should :-) The full version is not free ($30) but you get what you need for free:

    You can download SuperDuper! v2.6.2 right now and back up and clone your drives for free— forever!

  • neesh

    The way to do this using DiskUtility is to first format the drive using Diskutility and then copy over the files from the mounted iso to the newly formated drive using cp -R. Ex: cp -R /Volumes/mounted_iso/* /Volumes/formated_drive/

    When formatting be sure to pick the ntfs file system and make the disk bootable by picking the correct option from the Options menu in the erase tab.

  • Mark

    You do need the boot sectors, copying like this will work with some apps but not with a Windows ISO essential files cannot be copied, the image needs converting. ISO and IMG are different animals.


  • Related Question

    How can I keep multiple live/bootable ISO images on a single USB drive?
  • Keck

    I am looking to create a USB flash drive that I can put multiple live CD ISO images on and select which boots from startup. The ideal candidate supports Linux and Windows-based ISO images, and is relatively simple. It also must have some reasonable process for adding and removing an ISO image from the drive/list.

    Things that I'm not looking for in this specific question:

    • UBCD4Win or other swiss-army knife live CDs. The point is to boot any one of multiple CDs, not to boot a (certainly useful) utility CD.
    • Installing a single live CD to a USB drive. I'd like to have multiple ISO images, selectable at startup.

    I don't have a specific purpose in mind, possibilties include a single drive with a Knoppix variant, Ubuntu desktop, UBCD4Win for DOS, the Offline NT Password Cracker, etc.

    Flexible and easy to use are the name of the game!


  • Related Answers
  • Brandon Skari

    This is an interesting question. I can see it being very useful to have a single USB "master" LiveCD, instead of having so many different DVDs and pen-drives scattered around.

    There seem to be a number of different approaches to this, all of them doable:

  • Peter Mortensen

    YUMI – Multiboot USB Creator (Windows) also allows you to do it. Once set up, all you have to do is put the ISO image file on the drive.