In the event your Linux box experiences disk or file system issues you may receive a “Give root password for maintenance” prompt upon reboot. If you have your root password you can login but in the event your using ‘slide’ or ‘sudo’ for wheel access or you’ve just mis-placed your root password – you’ll need to reset it.
To reset your root password:
1. When the GRUB loader shows during boot press the spare bar to pause boot.
2. Select your boot kernel.
3. Type ‘e’ to edit the default kernel line.
4. Type ‘e’ again on the line that starts with ‘kernel’.
5. Add ‘init=/bin/bash’ to the end of the ‘kernel’ line then press enter.
6. Type ‘b’ to boot the modified kernel parameters.
7. Once you’re at the /bin/bash prompt you will need to remount the root file system as read/write in order to edit the passwd file:
# mount -o remount,rw /
8. Change your root password:
# passwd root
9. Remount the filesystem back to read only:
# mount -o remount,ro /
10. Reboot your server using CTR-ALT-DELETE.
11. You will now be able to login with your new root password and carry out the maintenance.