I have noticed that some of my machines do not switch off (since the upgrade to Precise) when I choose "Shutdown..." from the menu in the upper right corner of Unity. If the system is powered down or not is a kind of random. However, whenever I use the Terminal to sudo shutdown -h now
it will switch off the machine reliably. After having read this answer, I wonder what command Unity issues to initiate the shutdown (and power off) of the system?
Ubuntu's session indicator relies on
dbus
calls, for example the equivalent command in terminal would be this:As for whether or not some of the machines don't shutdown, I would assume either a bug or dbus calls are being blocked by something