Sometime you can’t remember root password. On Linux, recovering root password can be done by booting Linux under a specific mode: single user mode.This can be done using GRUB.
Follow these steps to reset the password when using GRUB:
- While booting the system, in GRUB menu, highlight the line for Linux and press e (for edit). This will take you to another screen where you can edit grub entry.
- Go to line which begins with kernel append single to the end of that line . And then append init=/bin/bash .So that now the line end with
…ro single init=/bin/bash
- Once the system finishes booting, you will be logged in as root. But root file-system is mounted as read only mode.So we should remount it as r+w mode. This can be done by
$ mount -o remount,rw / - now set new password using passwd.
- Again remount root file-system as read only (this is only for safety of file system).
$ mount -o remount,ro / Note:
if GRUB is locked by password ,one should use a live CD/USB and then change root (chroot) and edit grub file and comment password –md5 ……. Then reboot.