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--- linux:debian:grub [2021/02/13 08:34] – oscar
+++ linux:debian:grub [Unknown date] (current) – removed - external edit (Unknown date) 127.0.0.1
@@ Line 1: / Line 1: @@
-====== GRUB 2 ======
-===== Grub Configuration =====
-Your own GRUB settings are stored in the /etc/default/grub file. Edit this file to change GRUB2’s settings. Scripts are also located in the /etc/grub.d/ directory. For example, on Ubuntu, there are scripts here that configure the default theme. There’s also an os-prober script that checks the system’s internal hard drives for other installed operating systems — Windows, other Linux distributions, Mac OS X, and so on — and automatically adds them to GRUB2’s menu.
-When you run the update-grub command, GRUB automatically combines the settings from the /etc/default/grub file, the scripts from the /etc/grub.d/ directory, and everything else, creating a /boot/grub/grub.cfg file that’s read at boot.
-In other words, to customize your GRUB2 settings, you’ll have to edit the /etc/default/grub file and then run the update-grub command. Subsequently install/update the Grub loader in the disk.
-    # /etc/default/grub
-    # update-grub
-    # grub-install /dev/sdX
-    # grub-install --recheck /dev/sdX
-===== Repair, Restore, or Reinstall Grub 2 with Live USB =====
-Grub 2 typically gets overridden when you install Windows or another Operating System. To make Linux control the boot process, you need Reinstall (Repair/Restore) Grub using a Live CD.
-Create a live USB and boot system from USB
-Mount the partition your broken Linux installation is on. If you are not sure which it is, launch GParted (included in the Live CD) and find out. It is usually a EXT4 Partition. Replace the XY with the drive letter, and partition number, for example: sudo mount /dev/sda1 /mnt.
-<code>
-# mount /dev/sdXY /mnt
-</code>
-Now bind the directories that grub needs access to to detect other operating systems, like so.
-<code>
-# mount --bind /dev /mnt/dev
-# mount --bind /dev/pts /mnt/dev/pts
-# mount --bind /proc /mnt/proc
-# mount --bind /sys /mnt/sys
-</code>
-Internet access
-For internet access inside chroot:
-<code>
-# mv /mnt/etc/resolv.conf /mnt/etc/resolv.conf.org
-# cp /etc/resolv.conf /mnt/etc/resolv.conf
-</code>
-Now we jump into that using chroot.
-<code>
-# chroot /mnt
-</code>
-Now install, check, and update grub. This time you only need to add the drive letter (usually a) to replace X, for example: grub-install /dev/sda, grub-install –recheck /dev/sda.
-<code>
-# grub-install /dev/sdX
-# grub-install --recheck /dev/sdX
-</code>
-Now grub is back, all that is left is to exit the chrooted system and unmount everything:
-<code>
-# exit
-# umount /mnt/sys
-# umount /mnt/proc
-# umount /mnt/dev/pt
-# umount /mnt/dev
-# umount /mnt
-</code>
-Shut down and turn your computer back on, and you will be met with the default Grub2 screen.