You need to install keyutils as well to make it work on 20.04. I found this question on the same quest and came back to answer now that I figured it out. This is the top google result.
fstab mounting not working with Ubuntu 20.04
You need to install keyutils as well to make it work on 20.04. I found this question on the same quest and came back to answer now that I figured it out. This is the top google result.