Use your MacBook Air USB key as a Lion installer

Tips and Tricks no comments
July 4, 2011 at 8:19 pm

Apple packages an elegant little USB key with its MacBook Airs that allows you to restore Snow Leopard if your machine goes south.  But with many people upgrading to Lion, few will want to go through the process of downgrading to Snow Leopard and again to Lion if the machine goes bad.

Here is a way to upgrade your USB Key to Lion as well as your MacBook Air.

MacBenTosh has posted (thanks, Danny!) a video guide showing how to format the restore key into a drive that works like a normal 8GB rewritable Flash drive. To follow along with the instructions in the video you’ll need an instance of Windows running in a virtual machine, Boot Camp or a separate PC.  After restoring, the key will be shown as a 8GB drive.

From that point, Egg Freckles has posted a guide on how to create a Lion disc. Of course Lion will only be available from the App Store (or Dev site), but it’s nice to have a local, external installer.

  1. Purchase and download Lion from the Mac App Store on any Lion compatible Mac running Snow Leopard.
  2. Right click on “Mac OS X Lion” installer and choose the option to “Show Package Contents.”
  3. Inside the Contents folder that appears you will find a SharedSupport folder and inside the SharedSupport folder you will find the “InstallESD.dmg.” This is the Lion boot disc image we have all been waiting for.
  4. Copy “InstallESD.dmg” to another folder like the Desktop.
  5. Launch Disk Utility and click the burn button.
  6. Select the copied “InstallESD.dmg” as the image to burn, …
At this point, you’ll want to divert from these instructions and  choose the USB stick.  After a few minutes or so, you’ll have a Lion installer image.
In fact, it’s a little surprising that Apple doesn’t offer this themselves.  Perhaps they will?