How to reset the root password in CentOS7

There are various environmental and configuration issues in the process of moving bricks, and different errors are always encountered every time. A quick search on Google reveals that solutions that work for others may not work for you. The environment where I encountered the problem this time was:

Windows 10 Enterprise 2016 LTS

VMware® Workstation 14 Pro 14.1.0 build-7370693

CentOS Linux release 7.5.1804 (Core)

I forgot the root password of CentOS 7 installed in VMWare, so I had to reset it

1. Start the client

After entering the above interface, press e , and then enter the following interface

2. Modify the startup file

Move the cursor down and find the location of Linux16 and ro

Change ro rw init=/sysroot/bin/sh and press Ctrl + x to restart.

Let me explain here, some tutorials say to change it to rw init=/bin/sh , but I didn’t succeed! After changing rw init=/bin/sh restart the client and the following error message is displayed

It says that my BIOS has crashed the hw-PMU resources and the guest OS has disabled the CPU. Please shut down or reset the virtual machine. So I searched Google for a long time according to this error, and it said that the Windows system did not turn on CPU virtualization, so I restarted the laptop and entered the BIOS

I found that Intel virtualization Technology was turned on. The problem became more and more outrageous. I decided to change it to rw init=/sysroot/bin/sh !

3. Restart

After restarting the client, enter the following interface and execute chroot /sysroot

Run passwd root to change the root user password.

:/# passwd root
Changing password for user root
New password:
Retype new password:
passwd: Authentication token manipulation error

4. Update /etc/shadow

If an error message is displayed saying Authentication token manipulation error , it means that the root password change failed. The correct answer is here. Because there is no /etc/shadow file, as shown in the figure

There are only gshadow and gshadow- . Regenerate the shadow file through pwconv and set the permissions to -rw-r-----

5. Remount the root partition

mount -o remount,rw /

At this time, change the root password and find that it is OK

:/# passwd root
Changing password for user root
New password:
Retype new password:
passwd: all authentication tokens updated successfully 

Restart the client and log in successfully!

The above is the full content of this article. I hope it will be helpful for everyone’s study. I also hope that everyone will support 123WORDPRESS.COM.