Grub 2 recovery

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Grub 2 recovery

Procedure 1

1. Boot into Live CD 2. Enter the following commands:

sudo fdisk -l

And find your Ubuntu partition

3. Run the following commands:

sudo mount /dev/sda2 /mnt
sudo mount --bind /sys /mnt/sys
sudo mount --bind /proc /mnt/proc
sudo mount --bind /dev /mnt/dev
sudo chroot /mnt

4. Now reinstall Grub2

grub-install --recheck /dev/sda
apt-get install --reinstall grub2

5. Run as root

update-grub2

since in the previous steps the grub list was created with an /dev/sda4 as an entry.

Procedure 2

These are the commands for managing Grub 2. 1. Check the file /etc/default/grub and adjust the options accordingly 2. Install grub2 in MBR

grub-install /dev/sda

3. Auto-generate the boot menu for grub2:

grub-mkconfig -o /boot/grub/grub.cfg

4. Update the setup menu file:

update-grub

5. For recovering a node in guane run:

grub-mkconfig -o /boot/grub/grub.cfg
grub-install /dev/sda