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-Grub-EFI-in-Fedora-with-Fedora-Workstation-Live-media>

    

    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