At times we forget the root user password that we have set on our Linux machine. In this post, we will learn how to recover a lost root password in Linux. The procedure is most suitable of RedHat, Fedora and CentOS operating systems. Follow the below mentioned procedure:
Step 1: Reboot the machine and stop the countdown of the boot loader. To stop the countdown, press any key when the boot loader menu appears
Step 2: Use the arrow keys to highlight the default boot loader entry
Step 3: Press ‘e’ to edit
Step 4: Move the cursor to the line which starts with “Linux“
Step 5: Press the “End” key to move to the end of this line and type “rd.break“
Step 6: Now, Press Ctrl+x
Step 7: You will now see a “switch_root” prompt. At this prompt type the two below mentioned commands one after the other
switch_root:/# mount -o remount, rw /sysroot
switch_root:/# chroot /sysroot
Step 8: Now, the prompt will change. Next, use the passwd command to change the password
Step 9: Type the below command (Be very careful with spellings. There is dot (.) between / and ‘autorelabel’
# touch /.autorelabel
Step 10: Type exit twice
The system will run an SElinux relabel and reboot after doing the necessary updations. This might take sometime depending upon your system configuration, so be patient.
Congratulations! You have successfully reset the lost root user password.
View this video see the entire process in a detailed manner.