I have a 1 TB WD Passport portable drive that my main music collection is on. That is backed up in real time to NAS drive in my house, and the NAS drive is backed up every 1-3 months to another external drive (Seagate 3 TB) that I keep in a locked drawer where I work (so, offsite).
I only realised recently that the NAS drive backs up all of the music files - importantly - but does not back up the *.asd files that Ableton creates when you load a track as a clip in Ableton, warp it and save the clip settings. Don't know why as there appears to be no lower size cut-off. Anyhoo....
So if I lose my WD, I will not lose everything, but I will lose the *.asd files. It's not the end of the world (*touches wood*) as most of the clip settings are saved in another folder that I use to navigate Ableton to find tracks to play.
I have had my WD for about 5 years now (*touches wood again, and rubs it*), same as my Asus laptop.
Interested to hear from other people too.