Resetting forgotten root password on Centos/Red Hat
If you are desperate because you have forgotten root password, don’t be. This tutorial will show you how to reset root.
Boot the system and when you see the following screen, press any key

At the following screen, press e

It will take you the following screen

Highlight the line with vmlinuz in it by using the arrow keys and press e. The next screen will look like below

Now type single or init 1 at the very end of the line so.

Then press enter and b to boot the system with the new argument
The system will boot into single user mode and you will see bash prompt like below

Now change the password
Passwd                              
Enter new UNIX password:            
Retype new UNIX password:           
passwd: password **d successfully
type in the new password and then reboot
reboot                              
to restart the system.

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