First, convert the ISO to an IMG file using the hdiutil
utility.
hdiutil convert -format UDRW -o ~/path/to/target.img ~/path/to/ubuntu.iso
Note that since OSX tends to append a .dmg
suffix to the file name, you
will probably have to rename it to a .img
file.
Run the diskutil utility to get a list of the current devices.
diskutil list
Insert the USB drive and run the same diskutil command again.
diskutil list
Take a note of the node assigned to the USB drive (i.e. /dev/disk1
)
Unmount the disk.
diskutil unmountDisk /dev/diskN
Begin writing the image file to disk.
sudo dd if=/path/to/downloaded.img of=/dev/rdiskN bs=1m
After that has finished, eject the USB drive using the diskutil
utility.
diskutil eject /dev/diskN
That’s all there is to it, your new USB drive should be bootable!
(This was all very useful and relevant to me when I used to run Linux on a Macbook, hopefully it’s helpful to someone else)