Grub2 recovery with chroot
It may happen that grub breaks during an update and the system can not start anymore.
Here you can start the Kanotix-live-cd and repair grub with the Acritox-Installer.
But there is another alternative. You may try to repair grub with a chroot.
#### IMPORTANT! ####
The architecture of the live-CD has to be the same as the architecture of your system! 32-bit system requires a 32-bit live-CD, same for a 64-bit-system, here you need a 64-bit live-CD.
--> All commands are executed as root
* Boot with the Kanotix Live-CD.
* Open a terminal and execute the following commands. By typing
you will find out on which partition the system is installed and where grub needs repair.
From now on i will write /dev/
sdX? , you have to replace
sdX? with the right term of your partition.
* The filesystem will be mounted on /mnt
* Now the important devices of the filesystem /dev /proc /sys have to be mounted.
for x in proc sys dev; do mount --bind /$x /mnt/$x; done
* Changing into the installes system now:
*If needed, edit the /etc/default/grub files to fit your system again. After that run
* Now grub can be written in the MBR using this command
* When errors appear, then try to run
grub-install --recheck /dev/sda
* The chroot is left by the command
and /dev and the root filesystem will be unmounted by executing the following command
for x in proc sys dev; do umount /mnt/$x; done
umount /mnt
* Reboot and your system should start again.
