One of the premier troubleshooting features of Lion (Mac OS X 10.7) is Lion Recovery. If you ever have system or drive issues, Lion Recovery lets you boot your Mac into a special recovery mode to check or repair your hard drive, browse the Web for troubleshooting help, restore your drive from a backup, or even reinstall Lion itself. (See our hands-on with Lion Recovery for all the details.)
It's a convenient feature that, in theory, means you no longer have to carry a Mac OS X Install disc or a bootable external hard drive. But as I explained when Lion debuted, there are still good reasons to have a bootable installer disc or drive. For example, if you want to install Lion on multiple Macs, a bootable installer drive can be more convenient than downloading or copying the entire Lion installer to each computer.
But even for troubleshooting, a bootable installer drive has advantages over Lion Recovery. For starters, Lion Recovery doesn't include the full Lion installer--it requires you to download nearly 4GB of data before you can reinstall Lion--whereas a bootable installer drive contains the entire Lion installer, making installation much, much faster. And if you've got a Mac that doesn't support Lion Internet Recovery--a version of Lion Recovery based on special firmware--recovery mode may not even be available if your Mac's drive itself is having problems, whereas a bootable install drive will always be there for you. (Lion Internet Recovery is available on mid-2011-or-later Macs, as well as some older Macs that have received recent firmware updates.)
The problem for newer Macs
When Lion debuted, I explained how to create a bootable Lion-installer drive from the Mac App Store version of Lion. But if you have a Mac that debuted after Lion (any Mac from July 2011 or later), your Mac shipped with Lion pre-installed. In other words, you don't have a downloadable version of the installer unless you happened to purchase Lion for another, older Mac. AppleApple does offer a utility for creating an emergency Lion Recovery drive but, like the standard Lion Recovery feature, this drive requires you to download the full 4GB of Lion each time you want to install--it's better to have the full installer on a bootable drive. (In our testing, the official OS X Lion USB Thumb Drive doesn't work with Macs that shipped with Lion--it's designed for installing the OS on pre-Lion Macs.) Alles zu Apple auf CIO.de