I installed arch with a LUKS encrypted LVM (as shown in this video).
So now I would like to have a USB stick as an alternative method of unlocking my LVM at boot. When I’m at home I would keep the USB permanently plugged in my notebook so it boots without asking for the password. On the other hand I want the system to ask for the password when the USB is not connected.
What would be the best way to set this up?