GRUB 2¶

Recreate Grub-Menu¶

for BIOS-systems

grub2-mkconfig -o /boot/grub2/grub.cfg

on EFI-systems

grub2-mkconfig -o /boot/efi/EFI/centos/grub.cfg

or if you are using Rocky Linux

grub2-mkconfig -o /boot/efi/EFI/rocky/grub.cfg

remember last choice on reboot¶

taken from: https://nocache.org/p/make-grub-grub2-remember-last-choice-on-linux

cp /etc/default/grub /etc/default/grub.bak
vim /etc/default/grub

add or edit the parameters GRUB_DEFAULT and GRUB_SAVEDEFAULT

GRUB_DEFAULT=saved
GRUB_SAVEDEFAULT=true

generate GRUB configuration

grub2-mkconfig -o /boot/grub2/grub.cfg

make detailed boot-information visible¶

while it's possible to edit '/boot/grub2/grub.cfg' and also '/etc/default/grub' the better approach is to:

plymouth-set-default-theme details
dracut -f