How to password Grub2

There are several methods to protect the Grub in our favorite distribution. I particularly tried with this variant and with This other, but none worked for me. Maybe I was missing something and it is a shame, because when generating the passwords with Hash, the thing is more secure.

But anyway, I will show you one that did work wonders for me, and that asks me for username and password when I try to edit the Grub. The steps are simple:

1- We edit the file /etc/grub.d/00_header:

$ sudo nano /etc/grub.d/00_header

2- We add the following lines to the final:

cat << EOF
  set superusers="elav"
    password elav micontraseña
    EOF

In my case, I chose my nickname as a superuser, but you can choose whatever you want. If we want, we can add more users, and it would look like this:

cat << EOF
  set superusers="elav"
    password elav micontraseña
    password kzkggaara sucontraseña
EOF

We save and update the Grub.

sudo update-grub2

We reboot and when we try to edit the Grub with the key "and" It will ask us for username and password 😀