Lost Password

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The following applies to most linux boxen. It can be used to recover a lost password and is also called "rooting" the box. It can be used on an Ubuntu box (which has no root password) to recover the user password.

Generally it is easiest if the adopter brings the box in, but alternatively you can walk the adopter through the following: Alternatively you can use the instructions here

GRUB method

Edit the grub boot commands.

  1. start the computer booting up
  2. After a few (or 10 or 20) seconds you will see a screen that says... Grub Loading...3..2..1.
  3. During this screen, quickly press Esc, or hold down the shift key to go to the grub menu
  4. Next you will see several lines that start with Ubuntu, kernel 2.6..., this is the GRUB menu. hit the down arrow key as soon as you see this menu, it should select an option that ends with "recovery mode".
  5. Make sure that the recovery mode option is highlighted and press enter.
  6. This will bring up a menu with 4 options: resume, dpkg, root, and xfix
  7. select "root" from this menu. If you get a message that says "Give root password for maintenance (or type Control-D to continue):" then you have a root password set. Enter the root password here or if you don't know the root password follow the instructions under here
  8. You will be given a line at the bottom of the screen that should say root@freekbox:~#
  9. at this prompt, enter "passwd yourusername" (replace yourusername with the username you're trying to reset, or "oem" if it has not been changed).
    If you don't know the accounts username you can type "ls /home" for a list of all accounts on the computer.
  10. It will request that you enter a new password, and then once more to confirm. The screen will not show input as you are typing.
  11. once you enter your new password it should tell you "passwd: password updated successfully"
  12. type exit to go back to the recovery menu, then select resume to continue booting.

live CD method

If the box does not use grub to boot, one can boot the box using a live cd, a rescue floppy, or a Toms Root Boot disk, then login as root and proceed by entering the following commands one by one (hit enter after each line).

mount /dev/sda1 /mnt
chroot /mnt
passwd username    (replace username with the username you're trying to reset, or "oem" if it has not been changed.

sync
reboot

To find your username you can use ls /home

For Macs

For Mac computers at the yaboot prompt enter:

Linux rw init=/bin/bash

Once you get to the # prompt you will need to reset the terminal

reset

Now check the username

ls /home

and reset the users password

passwd usernamehere

Reset root password

  1. start the computer booting up
  2. After a few (or 10 or 20) seconds you will see a screen that says... Grub Loading...3..2..1.
  3. During this screen, quickly press Esc, to go to the grub menu
  4. Next you will see several lines that start with Ubuntu, kernel 2.6..., this is the GRUB menu.
  5. Select the first line in the list and press 'e'
  6. You should see something along the lines of
root   (hd0,0)
kernel /boot/vmlinuz-2.6.24-27-generic root=UUID=3deb56... ro quiet splash
initrd /boot/initrd.imb-2.6.24-27-generic
quiet
  1. Select the second line and press 'e' again.
  2. Remove 'ro quiet splash' from the end of the line and add 'rw init=/bin/bash'. Hit enter.
  3. Press 'b'. The box will now boot up and you will get a prompt that says 'root@(none):/#'
  4. At the prompt enter
/usr/sbin/usermod -p '!' root

Restart the computer.