Re: grub2 Question

[Stephen Morris]

On 1/11/22 08:26, Felix Miata wrote:
>  Robert McBroom via users composed on 2022-10-31 17:17 (UTC-0400):
>
> > Running Fedora 35 and trying to fix installed boot files on a third drive.
> > ~]# grub2-install /dev/sdc
> > grub2-install: error: this utility cannot be used for EFI platforms
> > because it does not support UEFI Secure Boot.
> > Secure Boot is turned off in the bios. The boot is from UEFI.
>  MBR is not a component of UEFI booting. The UEFI BIOS looks to the \EFI directory
>  on the ESP partition. Instead of grub2-install, do:
>
>  	dnf reinstall grub2-efi grub2-efi-modules shim
>
>  after appropriately following the directions on
>
> <https://forums.fedoraforum.org/showthread.php?313609-How-to-reinstall-Gru...
For both legacy boot systems and UEFI systems grub uses the config file 
from /boot/grub2/grub.cfg, which is updated by grubby when new kernels 
are installed. If you are happy with the format that grubby creates for 
the grub boot menu then you don't need to do anything for those changes 
to take effect. If you don't like the format produced by grubby then you 
can update grub.cfg by using the command grub2-mkconfig -o 
/boot/grub2/grub.cfg, but that rebuilds grub.cfg in its entirety by 
starting with configuration settings in /etc/default/grub, so you may 
need to play around with those to get the grub menu that you want. As 
other responders had specified, with UEFI systems you don't use 
grub2-install anymore.
Here is my /etc/default/grub contents for reference, at the moment the 
grub_background command doesn't work:

cat /etc/default/grub
GRUB_TIMEOUT=100
GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)"
GRUB_DEFAULT=saved
GRUB_DISABLE_SUBMENU=false
GRUB_TERMINAL_OUTPUT="gfxterm"
GRUB_CMDLINE_LINUX="rhgb quiet"
GRUB_DISABLE_RECOVERY="false"
GRUB_ENABLE_BLSCFG=false
GRUB_BACKGROUND=/boot/grub2/backgrounds/Galaxy-SDDM_3hu72.png

regards,
Steve