1.For Legacy Bios install mode,The Device for Bootloader Installation is at /dev/sda “Hard Disk name”
2…For UEFI install mode, is the “Device for Bootloader Installation” at EFI System Partition (/dev/sda# efi) or /dev/sda “Hard Disk name”?Which is the correct one?
When using grub-install for an efi system, it does not actually need to know the device for bootloader installation, it just needs to know where the EFI System partition is.
Use the option --efi-directory= mount point of /dev/sdXX
where sdXX is the EFI System partition
Regards
Neville