Linux reset forgotten root password

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

Change the root password, enter:
# passwd
Finally reboot system:
# sync
# reboot

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