Reset linux Root Password

My boot loader is GRUB (see LILO boot loader below)

)Following is the procedure to reset root password if you are using GRUB as a boot loader:

1. Select the kernel
2. Press the e key to edit the entry
3. Select second line (the line starting with the word kernel)
4. Press the e key to edit kernel entry so that you can append single user mode
5. Append the word Single (or letter S) to the end of the (kernel) line *need space bar to separate the word single with original command*
6. Press ENTER key
7. Now press the b key to boot the Linux kernel into single user mode
8. type "passwd" command to reset password:

My boot loader is LILO

At LILO boot loader type linux single and press [ENTER] key:
Boot: linux single
When you get the # prompt you will need to type passwd root to reset password:
# passwd
Reboot system:
# sync
# reboot


Reference: http://www.cyberciti.biz/faq/linux-reset-forgotten-root-password/