It is common problem with due boot system. accidentally, windows update or installation may overwrite MBR and you will loose grub(or LILO depend on your installation) boot loader screen. Boot loader may also corrupt and failed to load due to hard disk problem. Rescue disk is the solution of all the problems related to booting Linux kernel. Unfortunately, most of the people do not use rescue disk due to repair Linux installation. In my case, i have use rescue disk first time and successfully repaired fedora 7 boot loader in my Linux machine. Earlier, i was used to reinstall Linux in all boot failure cases after backing up data.

How To Repair

Follow simple steps to repair your boot problem:

  • Insert Linux Boot Disk or Rescue Disk to boot system in rescue mode. Type Linux rescue on the prompt to boot Linux on rescue mode. If you are using rescue disk then this step will not appear and you will directly reach to first boot screen without prompt.
  • You will be asked to choose “Choose a Language Screen” in the next step. select your language option from drop down, use TAB key to move from one option to another. Reach to ok button and press enter to continue.
  • Choose keyboard type in the next screen, then move control to ok button and press enter to continue.
  • At the Network Setup Screen select “no” then press enter to move to next screen because there is no use to configure network card here.
  • In the next two screen system will find Linux installation and you will get command prompt to recover your installation.
  • Type following command to command prompt and press enter. This command change default root directory to the /mnt/sysimage/. Rescue process mount linux installation by default to this location.

    chroot /mnt/sysimage/

  • Type following command and press enter to reinstall grub loader in MBR. “hda” parameter will depend on the hard disk drive you are using. If you are not sure, then type fdisk -l at command prompt and press enter to get hard disk partition detail. change parameter accordingly. recheck parameter used to check validity of installation on hda drive.

    grub-install –recheck /dev/hda

  • Now, type exit to exit from system. Remove boot media and reboot the system.
  • If boot screen appear but booting still fail. Try to change parameter in boot screen. Select boot option. Press e to edit boot option entry. Possible options are:
    root (hda0,0)
    root (hda1,0)
    root (hdb0,0)
    root (hdb1,0)
    root (sda0,0)
    root (sda1,0)
    root (sdb0,0)
    root (sdb1,0)

Written by Bala Krishna

Bala Krishna is web developer and occasional blogger from Bhopal, MP, India. He like to share idea, issue he face while working with the code.