Home Forums Mac Software Mac Operating Systems Using DU to Clone Lion to a APM firewire drive

"The external backup drive is unmounted and turned off during all software updates, to guard against updaters grabbing the wrong disk."

Never happened to me. In fact, Apple software updater only updates the main disk, which is used to boot the computer (it shows with a green downward arrow); my external (bootable and with a clone of the main one) always shows up in orange color with an exclamation mark on it.