Those who own 2011 iMacs now have the option of reinstalling Lion via the Internet thanks to a firmware update issued late Wednesday. The iMac EFI Update 1.7 gives current-generation iMacs the ability to use Lion Internet Recovery, which Apple first introduced as a Lion feature for MacBook Airs and Mac minis released in July.
Lion Internet Recovery enables Lion users to download and reinstall Lion from Apple’s servers when they experience an operating system meltdown, as long as they have a broadband connection. The feature mimics that of Lion’s built-in recovery drive that is installed on your Mac when you install Lion, but the advantage is that the computer is able to retrieve the data remotely in the event that your entire storage disk is experiencing problems. Take it from us, though: the faster and more reliable your Internet connection, the better, because this isn’t a tiny download.
It was only a matter of time before the 2011 iMacs gained this feature—early 2011 MacBook Pros also gained this feature recently via their own firmware update. In addition to Lion Internet Recovery, the EFI Update 1.7 also fixes compatibility problems with Apple's Thunderbolt Display and improves performance when the machine is in Target Disk Mode.
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Firmware update enables 2011 iMacs to reinstall Lion from the Internet