Solution of user and root forgetting password in virtual machine

！！！ The operation may be different with different versions , But the general process is like this , It is recommended to take a snapshot first , Changing the password , Prevent system problems

1. Ubuntu Forgot the password in

1.1 root Change Password

1.1.1 restart Ubuntu, Long press shift Get into grub menu , choice recovery mode Click enter ：

1.1.2 Get into "Recovery Menu" page , choice "root Drop to root shell prompt", Click enter

1.1.3 appear “[email protected]：~#” identification

1.1.4 Input passwd, Yes root Change the password

Problems encountered ： It's the part surrounded by yellow
This question must be answered with "mount -o rw,remount /" Order to solve

1.2 Ordinary users change password

1.2.1 restart Ubuntu, Long press shift Get into grub menu , choice recovery mode, Press e Editing , Remember not to enter

1.2.2 In the interface that appears , find ro recovery nomodeset Replace with rw single init=/bin/bash

1.2.3 Press ctrl+x Get into

1.2.4 Input passwd + [ user name ] Change the password , Yes successfully Prompt to prove that the password is changed successfully

2. Centos 6 Forgot the password in

2.1 After startup , Quick click e , You will enter the following interface

2.2 Click again on the e , Select the second term （ With kernel start ）, Click again on the e , Go to the edit page

2.3 Add... To the last line of the edit page 1 perhaps single , Carriage return confirmation

2.4 Finish the previous step , The interface returns to the second step , Press this time b , Enter the boot system

2.5 stay # Type in passwd root , To reset root password , After entering the new password, a message appears successfully, Prove that the modification was successful , Restart the system , Log in with a new password OK 了