Agradecimiento a: http://ubuntuforums.org/showthread.php?t=2105755
In past versions of Mac OS X, the built in backup tool, Time Machine was a lot less picky about where you back up your files to. You could even back up to a Samba file share if you enabled the «unsupported volumes» hack.
defaults write com.apple.systempreferences TMShowUnsupportedNetworkVolumes 1
But that ended with Snow Leopard. Starting with the release of OSX 10.7 Lion, Apple started cinching down on where you could back up your system to, ostensibly for security reasons. Now, with Mac OS X 10.8 «Mountain Lion», it’s gotten to the point where essentially the only places you can back up your system using Time Machine are either on another Mac OS X File Server or on an Apple Time Capsule. My assumption is that their intent is merely to bolster their hardware sales.