Remove The Grub Password

a) If you are using Debian Linux you need to modify /boot/grub/menu.lst file:
# cd /mnt/boot/grub
# vi menu.lst

b) If you are using Suse Linux you need to modify /etc/grub.conf file
# cd /mnt/etc
# vi grub.conf

If you are using Red Hat / Fedora Linux you need to modify /boot/grub/grub.conf file
# cd /mnt/boot/grub
# vi grub.conf
Once file opened using a text editor, locate password line and remove it:
password --md5 $1$9sdflksdf/sdf44k

Fig.03: Removing The Grub Password Line

Save and close the file. Reboot the system.
# sync; sync
# cd /
# umount /mnt
# reboot

Change Root password

Now your Grub password is removed from the system. You need to login to the system without any password. To restore root user password boot system into a single user mode.

1) At Grub prompt press 'e' to edit command before booting.

2) Select second line

3) Again, press 'e' to edit selected command

4) Type the following line
init=/bin/sh
OR
init=/bin/bash

Fig.04: Booting into a single user mode using Grub

4) Press 'b' to boot system.

5) Now you are at shell prompt. Just change root password with the passwd command:
# passwd
Please note that depend upon your Linux distribution you may need to remount root partition in read/write mode before running the above command.

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