Reset root password (Ubuntu Linux) without CD

Resetting your systems root password may be a necessary step if you have forgotten it or have bought a used computer which you don't want to setup anew. Doing so without any installation medium saves you a blank CD and a bit of time.

To start, restart your computer and get to the GRUB menu by pressing Shift while booting. Point your cursor to the Recovery mode option:

Press e to edit the boot options. There, look for a line that looks like this: linux /boot/vmlinuz-3.2.0-18-generic root=UUID=b8b64ed1-ae94-43c6-92\d2-a19dfd9a727e ro recovery nomodeset:

The line will differ depending on your version and kernel but should have about the same syntax. Remove the last part of line which is ro recovery nomodeset and replace it with rw init=/bin/bash:

This will cause a command line to be opened on startup. Press F10 now to reboot the machine and get to the command line. Once you are there, enter:

/usr/sbin/usermod -p '!' root

(If you get an error by copying and pasting above command, try replacing the quotation marks.) Now reboot the machine and the root password should be reset. The changes you did to the boot options will also reset automatically, so you do not have to change them back.

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14 thoughts on “Reset root password (Ubuntu Linux) without CD”

  1. Thanks for the tip. One hint: If you’re using a KVM switch (like I was), the Shift-on-boot trick might not work. The Solution: just connect the keyboard *directly* to the system in question.

  2. OK its working, Thanks Very Much, Ivebeen using other methods but this was a key to succes.
    OK to działa, Dziękuję bardzo za podpowiedź, używałem innych metod ale to był klucz do sukcesu.

  3. After doing the above mentioned process it is strucking at syscenter_do_call and here sroll and caps lock blinking continuosly

  4. My acer Chromebook c7 has a dual booting system as I have just downloaded Ubuntu 12.4.
    At the end of the download, I entered a password as requested which has not been taken by the machine. However, the administrative account has ***** as password which I never set. I am unable to access the “Administrator” account. How do I proceed? Thank you.

  5. as u have written above inmy grubmenu it is showing
    ro i915.modeset=1 quiet splash $vt_handoff $nomodeset

    so what to edit in the above case

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