How to Boot from a USB drive with an Intel Mac

Dec 25th, 2008

USB Symbol Photo courtesy of Wikipedia

With the latest MacBooks shipping without FireWire, meaning no Target Disk Mode, what can a user do when faced with hard drive problems? How can you properly troubleshoot with no way to boot from an external drive? The answer is easy, just boot from a USB drive instead – Here’s how.

With users and technicians used to using FireWire for this, many don’t realize one of OS X’s little secrets – that an Intel Mac can boot from an external USB Drive and it’s very easy.

Here’s what you do to create a bootable USB Drive:

- Shut down the computer and connect the USB Drive.

- Insert the OS X Install DVD and hold down “C”.

- Install OS X onto the USB Drive.

- Be sure to choose the USB Drive and not your computer’s drive!

Note: Make sure there’s nothing of value on your external drive. I’d recommend backing up the drive onto your computer, installing and then putting it back when you are finished.

- When finished, shut down the computer.

- Start up the computer and hold the Option key.

- Choose the USB Drive and boot.

You can then put SuperDuper! images on the drive for easy reinstalling, use it as a Time Machine volume, or just have it as a storage device.