bootable usb on osx
Open the Terminal Application. Type command to convert the .iso file to .img using the convert option. hdiutil convert -format UDRW -o ~/path/to/target.img ~/path/to/ubuntu.iso Insert your flash media. Type command to determine the device node assigned to your flash media (e.g. /dev/disk2). diskutil list Type command to unmount the flash (replace N with the disk number from the last command; in the previous example, N would be 2). diskutil unmountDisk /dev/diskN Type DD command (replace /path/to/downloaded.img with the path where the image file is located; for example, ./ubuntu.img). sudo dd if=/path/to/downloaded.img of=/dev/rdiskN bs=1m Type command to eject the flash drive. diskutil eject /dev/diskN Restart your Mac and press alt/option key while the Mac is restarting to choose the USB stick as the boot disk.