To encrypt GRUB

First generate the password in the format: grub2-mkpasswd-pbkdf2

Then the following two files are backed up:

cp /boot/grub2/grub.cfg /boot/grub2/grub.cfg.bak may cp /boot/grub2/grub.cfg{,.bak}

cp /etc/grub.d/00_header /etc/grub.d/00_header.bak be cp /etc/grub.d/00_header{,.bak}

After editing the file as follows

vim /etc/grub.d/00_header

Added to the end

cat << EOF
set superusers="root"
password_pbkdf2 root 【grub.pbkdf2.sha512.10000.A76AA83747A4FBB7B3BDFB426F6764C9D2A518DEC19F6B3CC452D

BA87BDE1C86C9F50A229C19F61BD4098D88551DE0F238D951934812D703A

F8BEF7A7274583E.2B0F0F2391E1FEB24060A6C51E7FEB034073E3C7E5D3706A9084F03

2883B1FAC96A960B6FF14BCFCA977B36BB81DFE654D7E1B39F4D78001B777DD25216A9FC6】
EOF

Data in brackets when generating a password

last step

[root@localhost ~]# grub2-mkconfig -o /boot/grub2/grub.cfg

Restart it