Automatically Restart Your Mac if it Freezes in OS X Lion
Your Mac will automatically restart itself if it freezes, thanks to a new feature in OS X Mountain Lion and Mac OS X Lion. Tucked away in “Energy Saver”, the auto-restart ability is an option that can be disabled if for whatever reason you don’t want your Mac to basically fix itself in the event of a disaster.
To toggle this feature to auto-reboot when a serious system freeze happens, just do the following in the OS X system settings:
- Launch System Preferences
- Click on “Energy Saver” and look for “Restart automatically if the computer freezes”
Macs very rarely freeze, but if you do encounter random freezes and crashes, it may be a good idea to test your RAM for defects. At this point, Mac OS X is so refined that it’s very unusual for the entire operating system to go down or simply freeze, especially with any regularity, so this can be an indicator of something greater than a random one-off freeze.
Regardless of the causes of a system freeze, this is a great feature. If you were wondering why it’s tucked into Energy Saver, it’s probably because a restarted Mac can sleep the display and hard drives, whereas a frozen Mac will continue to display the screen and spin the hard drive, wasting energy. This is just one of many new and subtle features tucked into Mac OS X 10.7 Lion, but, curiously, it was removed in later versions of OS X.
If you want to adjust the automatic reboot on freeze feature in OS X Yosemite and OS X El Capitan, you’ll need to turn to the command line instead.