Content #
- grubx64.efi This is what makes GRUB2 work on an EFI/UEFI machine.
- shim64-almalinux.efi and shimx64.efi These files go along with the BOOTX64.EFI file to make Alma work on a Secure Boot machine.
- mmx64.efi This is part of the Machine Owner Key system, which also helps out with Secure Boot.
- BOOTX64.CSV This file works with the fallback bootloader and contains a boot menu entry for this installation of Alma. (If multiple operating systems were installed, they would all have their own BOOTX64.CSV files.)
- fbx64.efi The fallback bootloader. Its job is to recreate the boot manager options that are built into the firmware in case they somehow get deleted. It does this by scanning the BOOTX64.CSV files that are in the subdirectories for any operating systems that are installed.
If you peek inside BOOTX64.CSV, you’ll see this:
[root@alma-efi almalinux]# cat BOOTX64.CSV
´´shimx64.efi,AlmaLinux,,This is the boot entry for AlmaLinux
BOOTX64.CSV file is not an ASCII text file as most Linux configuration files are. Instead, it’s a UTF-16 UNICODE file. Let’s say that you’ve created a boot.csv file in your home directory. You can convert it with the iconv tool, like this:
iconv -t UTF-16 < ~/boot.csv > BOOTX64.CSV