Create Bootable USB on a Mac

Download your ISO first

Open the Terminal (in /Applications/Utilities/ or query Terminal in Spotlight)

Convert the .iso file to .img using the convert option of hdiutil

hdiutil convert -format UDRW -o /Users/dennis/Downloads/ubuntu-14.04.3-desktop-i386.img /Users/dennis/Downloads/ubuntu-14.04.3-desktop-i386.iso

Reading Master Boot Record (MBR : 0)…

Reading Ubuntu 14.04.3 LTS i386 (Apple_ISO : 1)…

Reading (Windows_NTFS_Hidden : 2)…

.......................................................................................................................................................................

Elapsed Time: 4.670s

Speed: 217.3Mbytes/sec

Savings: 0.0%

created: /Users/dennis/Downloads/ubuntu-14.04.3-desktop-i386.img.dmg

Run diskutil list to get the current list of devices

diskutil list

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *751.3 GB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_CoreStorage Macintosh HD 750.4 GB disk0s2

3: Apple_Boot Recovery HD 650.0 MB disk0s3

/dev/disk1 (internal, virtual):

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS Macintosh HD +750.1 GB disk1

Logical Volume on disk0s2

C1E17208-C4A2-4DF9-8B91-CAC2275AAE42

Unlocked Encrypted

Insert your flash media

Run diskutil list again and determine the device node assigned to your flash media

diskutil list

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *751.3 GB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_CoreStorage Macintosh HD 750.4 GB disk0s2

3: Apple_Boot Recovery HD 650.0 MB disk0s3

/dev/disk1 (internal, virtual):

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS Macintosh HD +750.1 GB disk1

Logical Volume on disk0s2

C1E17208-C4A2-4DF9-8B91-CAC2275AAE42

Unlocked Encrypted

/dev/disk2 (external, physical):

#: TYPE NAME SIZE IDENTIFIER

0: FDisk_partition_scheme *8.1 GB disk2

1: DOS_FAT_32 MYLINUXLIVE 8.1 GB disk2s1

Run diskutil unmountDisk /dev/diskN

diskutil unmountDisk /dev/disk2

Unmount of all volumes on disk2 was successful

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).

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

sudo dd if=/Users/dennis/Downloads/ubuntu-14.04.3-desktop-i386.img of=/dev/rdisk2 bs=1m

Password:

1015+0 records in

1015+0 records out

1064304640 bytes transferred in 238.599983 secs (4460623 bytes/sec)

Run diskutil eject /dev/diskN and remove your flash media when the command completes.

diskutil eject /dev/disk

Disk /dev/disk2 ejected

Restart your Mac and press alt/option key while the Mac is restarting to choose the USB stick.