After Mac OS X 10.7 Lion was released, new Mac mini and MacBook Air models shipped with no installation media — a first for Apple, which had always included the operating system on a floppy disk or optical disc. Owners of earlier MacBook Air models received a USB flash drive, which made sense for first-time buyers who might never own a DVD drive nor have another computer in the household with a DVD drive. But now, no external boot media is included at all on those Mac models, or any other current Macs now shipping with Lion.
Older machines that are capable of running Lion are upgraded through the purchase of a $29 installer that’s downloaded from the Mac App Store, or via the $69 OS X Lion USB Thumb Drive. The downloadable installer can be used to create a bootable DVD or USB drive as well at no additional cost by following Dan Frakes’ instructions at Macworld.
But neither the Apple thumb drive nor a user-created Lion installer on a bootable DVD or drive can be used to start up the 2011 Mac models released — nor, we expect, those to come. There’s no good reason for this that we’re aware of. You can download the same precise version of (at this writing) 10.7.2 from the Mac App Store that’s installed on a 2011 Mac mini or MacBook Air, and create a bootable installer from the package. It just won’t boot those models.
Instead, you can create a bootable clone using Carbon Copy Cloner or Super Duper, or install Lion on an external drive as an emergency backup measure. I also recommend using Lion Recovery Disk Assistant to create a bootable recovery drive that can be used as discussed below if you have a complete drive failure.
The reason to boot from an installer — and the frustration at not being able to have a bootable installer for 2011 models — is to create a clean installation of a new drive or erase and reinstall an existing drive. You might need to do that if a drive has a physical failure or if you’re upgrading your internal storage capacity. A cloned backup can be useful for the same reason, unless the clone contains flaws that caused a system installation to go bad.
If you’re put in that situation, and your clone isn’t the solution, or you’re trying to set up a system from scratch with a fresh Lion installation, Apple gives you access to the full downloadable installer, part of its broad set of Lion Recovery tools which don’t rely on you having to have external media or drive, although you can take advantage of a USB drive.
Lion Recovery encompasses many different methods that center around booting from a limited system that can be embedded in a partition on your Lion boot drive (which it is, by default), installed on a bootable USB thumb drive (which works even with the 2011 models), or even downloaded over the Internet from Apple servers.
The easiest way to access Lion Internet Recovery with a functioning drive that had Lion properly installed on it is to hold down Command-R while your Mac starts up. Failing that, if you took my advice above and used Lion Recovery Disk Assistant, you can startup from the USB drive and use Lion Recovery options. Without either a working startup partition or a recovery disk, a 2011 model and all current models of iMac and MacBook Pro can retrieve the Recovery HD over the Internet (a roughly 650 MB download), which is installed on the target drive, and then the system restarts into Lion Recovery.
You can select Reinstall Mac OS X at this point, and the recovery system downloads the 4 GB or so Lion installer, and then runs the installation process. The computer’s serial number is sent to Apple to confirm that the computer qualifies for a Lion reinstallation. The installer isn’t retained on your Mac, but that doesn’t matter for 2011 Macs — the downloadable installer from the Mac App Store can’t be used to create a bootable disk, as noted above.
We at TidBITS have talked extensively about this scenario, because not everyone has the bandwidth to retrieve 4 GB or 4 GB plus 650 MB of files in less than a full day. Others may have metered service and the retrieval could cost them overage fees. It seems absurd that Apple can’t update its own USB thumb drive installer to work with 2011 models, nor allow users to create their own. This is the way everything will apparently be with future Apple models. Most users don’t need to reinstall their systems, and thus the pain point only occurs when someone without the right combination of skills and bandwidth hits the wall.