OK, after a bit more research, I think I get it but I'm still not sure.
Goal:
1 disk (so 1 volume group) with several logical volumes (/boot, /, /home
etc.)
1 disk as /data (so 1 volume group for 1 logical volume)
1 disk as /backup (so 1 volume group for 1 logical volume)
That's for LVM.
I just don't have experience with creating mounting points with random names
(data, backup).
Now what about LUKS? Since I can set up each drive to be encrypted (that's 3
volume groups over 3 different drives), does that also means one encryption
passphrase? I wonder because it's encryption over different physical volumes.
I hope it does. More reading, less guesses, I suppose.
So this is supposed to be LVM over LUKS, with /boot encrypted.