GRUB2 plain-text passwords work but encrypted passwords do not

Issue

• Cannot get grub2 pbkdf2 encrypted (hashed) passwords to work as described in the RHEL 7 Administration Guide

  • Plain text passwords work as expected by putting something like the following in /etc/grub.d/01_users or /etc/grub.d/40_custom

    cat <<EOF
    set superusers="john"
    password john johnspassword
    EOF
    

  • Changing the same to use encrypted passwords (as follows) does not work

    cat <<EOF
    set superusers="john"
    password_pbkdf2 john
    grub.pbkdf2.sha512.10000.049117C9....
    EOF