Transferring files from ATV to External HD

I am in the midst of copying all iTunes music files from my ATV to an external HD. Everything seemed to be working fine and the message “Copying current iTunes media to external drive. The ATV will automatically restart when complete…” A few minutes into it, the screen went into the sleep mode with my screen saver pics showing and I get no response from the remote. Is this normal? Do I need to unplug the ATV and restart it? Or do I need to be more patient and let it finish?

Anybody out there?

Yes, the process can take some time (up to 5 hours). The screensaver may come on, however the AppleTV will restart automatically when the process is complete.