Rescue System

When the system fails to boot, "Enable/disable rescue mode" allows the user to access the hard disk. 

The Rescue system configured uses Rescatux. After enabling it, boot up, and you will need to locate the original hard disk first by running the command

lsblk

You should be able to see hard disk devices, for example /dev/sda1, which should correspond to your hard disk size (e.g., 50GB).

Next, simply mount the device to a folder, such as /mnt, using the command

sudo mount /dev/sda1 /mnt

Make any necessary changes.

Disable rescue mode once you are finished.