v7.5

+ DietPi-FirstBoot | On x86_64 BIOS systems, set the GRUB install device to the obtained root drive. Naturally, we cannot know on image create, what the install drives path/name is, or what type it is and UUIDs do not exist for the raw drives, where the bootloader needs to be written to. With a wrong drive in debconf, on a GRUB upgrade or install, the system can become unbootable. GRUB (or the Debian GRUB maintainers) implemented some additional checks to prevent such cases, due to many bug tracker reports, but the issue is generally not ruled out 100% and it requires a manual selection of the bootloader drive on package upgrade, when the stored one does not exist, else the upgrade fails. For our x86_64 images we know that those are full drive images with "our" bootloader stored on the same drive where the DietPi root partition is found, so we can automatically detect and apply it. Even if it is a customised image, this step cannot make things worse compared to the hardcoded "/dev/sda", which is a pure guess that most x86_64 systems will run on the first SATA drive attached to the system.

rootfs/var/lib/dietpi/services/dietpi-firstboot.bash

@@ -301,6 +301,13 @@ _EOF_
 		# shellcheck disable=SC2015
 		(( $wifi_enabled )) && ifup wlan$index_wlan || ifup eth$index_eth
 
+		# x86_64 BIOS: Set GRUB install device: https://github.com/MichaIng/DietPi/issues/4542
+		if (( $G_HW_MODEL == 10 )) && dpkg-query -s grub-pc &> /dev/null
+		then
+			local root_drive=$(lsblk -npo PKNAME "$(findmnt -Ufnro SOURCE -M /)")
+			[[ $root_drive == '/dev/'* ]] && debconf-set-selections <<< "grub-pc grub-pc/install_devices multiselect $root_drive"
+		fi
+
 	}
 
 	#/////////////////////////////////////////////////////////////////////////////////////