How to reset root password in Linux

    Debian and Ubuntu

    Method 1: Using recovery mode (GRUB)

    1. Open the hypervisor console and reboot the VM.

    2. When the GRUB menu appears, quickly press e to edit the boot entry.

    3. Find the line that starts with:

      linux /boot/vmlinuz...

    4. Move to the end of that line and append:

      
rw init=/bin/bash

    5. Press Ctrl + X or F10 to boot.

    6. The system will boot into a root shell.

    7. Remount the filesystem as read/write (if needed):

      mount -o remount,rw /

    8. Change the password:

      passwd root

      or for a specific user:

      passwd username

    9. Reboot the system:

      exec /sbin/init

      or simply:

      reboot -f

    After reboot, log in using the new password.

    AlmaLinux and CentOS (RHEL-based systems)

    Method 1: Using GRUB console access

    1. Open the hypervisor console and reboot the VM.

    2. At the GRUB menu, highlight the default entry and press e to edit.

    3. Find the line starting with:

      linux16

      or, on newer systems:

      linux

    4. At the end of that line, append:

      rd.break

      This boots the system into the emergency (initramfs) shell.

    5. Press Ctrl + X to boot.

    6. Once at the shell prompt, remount the system as writable:

      mount -o remount,rw /sysroot

    7. Enter the chroot environment:

      chroot /sysroot

    8. Change the password:

      passwd root

      or:

      passwd username

    9. Relabel SELinux contexts (important for RHEL-based systems):

      touch /.autorelabel

    10. Exit and reboot:

      exit
reboot

    After the system reboots (relabeling might take a few minutes), use the new password to log in.

    Published