Reset forgotten root password for Linux

 Linux operating systems are well known for their tight security, stability and fast responsiveness but what if you forget your root password ?
It sometimes can get chaotic and you may end up yourself  being locked away from your own computer. You can reset forgotten root password under Linux by booting system into single user mode or emergency mode (also known as rescue mode).

For GRUB boot loaders

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 letter S (or word Single) to the end of the (kernel) line
6. Press ENTER key
7. Now press the b key to boot the Linux kernel into single user mode
8. At prompt type passwd command to reset password:

You need to mount at least / and other partitions:

# mount -t proc proc /proc
# mount -o remount,rw /

Change the root password, enter:

# passwd 

Finally reboot system:

# sync
# reboot


For LILO Boot loaders

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