Is wifi sync supposed to wake my 2011 mac mini runing mtn lion from sleep when I automatically or manually wifi sync on my iPhone/iPad? Does it matter if the mini is connected via ethernet or wifi?
If your computer is asleep or shut down, or iTunes is closed, there's no access to the iTunes library. Wake up or start the computer, sign into the user account on your computer from which you initially enabled Wi-Fi Syncing, and open iTunes to regain access to the library.