I'm recently made my old laptop into a server using Ubuntu Desktop 15.04. But because my laptop has an almost dead battery I want Ubuntu to save all data that it's on (or at least close the running programs) and safely shut down. How can I make sure Ubuntu does this when the AC adapter is unplugged?
I might be able to get this done easily by just adjusting the critical battery level to 95-ish. But I don't know what Ubuntu does during shutdown at critical battery level. If this could be the fix then I'd like to know: what does Ubuntu do when shutting down at critical battery level?