Resetting password on linux root password

How to Reset the Root Password in Linux

In Linux, regular users and superusers are allowed to access services via password authentication. In the case a regular user can’t remember his/her password, a superuser can reset the password of a regular user right from the terminal. However, what if the superuser (or root user) loses his/her password? They will have to recover the lost password prior to booting into the login screen. This allows any malicious user with physical access to your Linux host to gain complete ownership. This article takes a look at how to recover a lost root password in Linux using two different methods.

Note: the method of resetting a root password is similar for most distros. Here we demonstrate the process using Ubuntu. We are also using “root password” throughout the tutorial for simplicity, but it can be interpreted interchangeably as the superuser password.

Also read: How to Easily Rename Files in Linux

1. Reset Lost Linux Root Password from the Grub Menu

1. First and foremost, to recover a lost root password, we need to restart the Linux host, assuming you forgot the password for root.

2. Once the GRUB page appears, quickly select the “*Advanced options for GNU/Linux” option by pressing the down arrow key and Enter button.

3. Now press e to edit the commands.

You need to modify it or change it from “read-only” mode to “read-write” mode. Find the line beginning with “Linux.” Look for ro and change it to rw . Add init=/bin/bash at the end of the line.

4. Press F10 . This will display a screen with a prompt.

5. Mount your root file system in read-write mode:

6. You can now reset your lost root password by using the following command:

Once you are done, type:

This will exit the prompt and reboot the computer.

Also read: How to Mount a Windows Share Folder on Linux

2. Reset Lost Root Password Using Live CD

If you have a Linux Live CD/USB, then you can boot into it and use it to reset the root password.

1. Download the latest version of Ubuntu, and create a bootable Live CD/USB from it. Boot your system from the removable drive as opposed to your hard drive.

2. On the display screen select “Try Ubuntu.” This will bring you to the Live CD desktop.

3. Open the terminal and type the following command to become root:

4. Find the location of the hard disk partition using the following command:

In most cases it will be “/dev/sda1,” although it can differ depending on how your hard disk is partitioned.

5. Mount the hard disk partition of the system to be recovered using the following command:

6. At this point we need to jail ourselves in the “mnt/recovery” directory. This means that we are pretending to be on the regular Linux filesystem. This is simply known as chrooting.

7. Use the following command to reset your Linux root password:

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8. Once completed, exit from the chroot shell:

9. Unmount the root partition:

and exit your root:

10. Lastly, remove the Live CD and reboot into your Linux system.

Changing the root password in Linux is easy once you get over the intimidation of the extra steps you have to take. Do note that anyone who has access to your computer can use this method to reset your superuser or root password. If you would like to be more cautious with who has access to these sorts of privileges, you should encrypt your hard disk so that it can’t be booted into or mounted easily.

Frequently Asked Questions

1. How does full disk encryption affect my ability to change my root password?

Although encryption can complicate things when you’re trying to repair a problem on Linux, this is not the case when you’re trying to change the root password. You can still do it easily from grub as described above as long as you are able to gain access to the disk.

The only difference now is that outsiders won’t be able to just slide in and do the same themselves.

2. What is the difference between root and superuser password?

In most cases, the root user is the same as the superuser. Changing the root password should also change the superuser password. In Ubuntu, the superuser is the one with User ID 0. If you have configured another user with the UID 0, then in this case, the root and superuser passwords are not the same.

3. Can I create an expiration date for passwords?

Yes, you can! Using the -x flag, you can set the lifespan for the password of a particular user. For example, typing passwd -x 30 root will make the root password valid for only 30 days. Upon expiration, you must change the password.

Additionally, you could use the -w flag to set the number of days required for an advanced warning about the need to change the password . Typing passwd -w 7 root will send you warnings about changing the root password a week prior to the deadline you previously set with the -x flag.

Want to keep digging into Linux? We have a guide for setting up Bluetooth on Linux. You can also check out our list of tools to create your very own Linux distro!

Miguel has been a business growth and technology expert for more than a decade and has written software for even longer. From his little castle in Romania, he presents cold and analytical perspectives to things that affect the tech world.

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Как сбросить пароль в Linux


Давайте рассмотрим несколько способов сбрасывания системного пароля в Linux. Вы наверное знаете, что у пользователя root есть права на изменение пароля любого пользователя в системе. А что если вы забыли пароль от рута? Вот об этом и пойдет речь в статье.

При восстановления пароля (рута или любого другого пользователя) встречаются две различные ситуации, требующие разного подхода.

Когда можно использовать GRUB

    После этого вы либо увидите приглашение для рута, либо восстанавливающее меню, где нужно выбрать строку с рутом. Используйте passwd для того чтобы изменить пароль у любого пользователя

  • Выполните команду reboot для перезагрузки системы и затем авторизуйтесь с новым паролем
  • Также следует заметить что некоторые дистрибутивы создают режим восстановления во время установки. Если в вашем меню GRUB есть такой пункт, вам не нужно производить все вышеперечисленные действия, просто выберите режим восстановления, а затем приглашение для рута, в последующем диалоговом окне.

    Когда нет возможности использовать GRUB

    Если вы не используете GRUB по каким-то причинам, вы можете восстановить пароль с помощью live CD (Я буду использовать Ubuntu live CD, вы можете взять любой другой). Просто следуйте дальнейшим инструкциям:

    • Загрузитесь с live CD
    • Выберите «Попробовать Ubuntu без изменений на вашем компьютере» (Try Ubuntu without any changes to your computer)

  • Когда система будет готова, запустите окно терминала и приготовьтесь к выполнению некоторых действий в командной строке
  • Напечатайте в окне терминала sudo fdisk -l. В результате мы узнаем, в какой раздел диска установлен линукс и непосредственно имя самого жесткого диска, в представленном примере нужный нам раздел называется /dev/sda1 . Если вы точно знаете нужный раздел, этот шаг можно пропустить.

    Далее нам нужно монтировать линукс-раздел. Для этого создайте папку, в качестве точки для монтирования, используя команду: sudo mkdir /media/linx_part

    Примонтируйте линукс-раздел командой sudo mount /dev/sda1 /media/linx_part

  • Измените рута в примонтированном разделе — sudo chroot /media/sda1
  • Используйте passwd для изменения текущего пароля на новый

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    How to Reset Ubuntu Password in 2 Minutes

    Last updated August 4, 2020 By Abhishek Prakash 375 Comments

    Brief: If you forgot your user password on Ubuntu, don’t worry. You can reset an Ubuntu password very easily. This guide explains an easy method for changing the root password on Ubuntu. The method should also be applicable to other Linux distributions.

    Forgot your Ubuntu login password? It happens.

    If you haven’t used Ubuntu for some time, it’s only natural to not remember the password. The good news is that you don’t need to reinstall the entire operating system because of it. You can recover Ubuntu passwords easily.

    The method mentioned here works for resetting an Ubuntu password in VMware, dual boot or single install. All you need is a little bit of patience and to run a couple of commands. You’ll reset the root password within minutes.

    Using Linux on WSL?

    It’s a bit different for WSL. You may follow the steps for resetting Linux password in WSL here.

    Reset Ubuntu password from recovery mode

    If you prefer watching videos to reading text, I’ve also made a video of this tutorial. Don’t forget to subscribe to our YouTube channel for more Linux tutorial videos.

    Step 1: Boot into recovery mode

    Switch the computer on. Go to the grub menu. Generally, it appears automatically – if not, then hold down the shift key or press Esc key until the boot menu appears.

    If you’re using Oracle VirtualBox or VMware, you have to hold down the shift key when the logo of Oracle or VMware appears.

    In the grub menu, select the “Advanced Options for Ubuntu”:

    In here, you’ll see the option to go to recovery mode:

    It will bring you to a black screen with several lines of output being displayed in a flash. Wait for a few seconds here.

    Step 2: Drop to root shell prompt

    Now you’ll be presented with different options for recovery mode. Here you need to choose “Root – Drop to root shell prompt“. Just press the enter key to select this option. Like in the picture below:

    You’ll see that when you select the root shell prompt option, an option to enter commands appears at the bottom. This is your root shell prompt and this is where you’ll use the commands to reset the password.

    Step 3: Remount the root with write access

    You need to have write access to the root partition. By default, it has read-only access.

    Use the command below to remount it with write access:

    Step 4: Reset username or password

    Here, you’ll be given root access. Use the following command to list all the users available:

    Based on this command, choose the “username” for which you want to reset or (say) hack the password. Now, use the following command to reset the password for the selected “username“:

    It prompts for a new password. Enter the new password twice:

    Voilà! There you go. You have just successfully reset the password. Now exit the root shell prompt:

    When you exit, you’ll be back at the recovery mode menu. Select the normal boot option here.

    There will be a warning about graphics mode compatibility. Don’t worry. A complete reboot will fix any issues with this.

    You should now be able to log in with the new password.

    Possible Troubleshoot:

    While entering the new password you might be prompted with Authentication token manipulation error like this:

    The reason for this error is that the file system is mounted with read access only. Change the access and remount the file system in the following manner:

    Now try to reset the password again. It should work now.

    As you can see, it is extremely easy to change Ubuntu password even if you’ve forgotten it. It will barely take a few minutes.

    Alternate method to reset Ubuntu pasword

    If for some reason you have difficulty dropping to the root shell and changing the password, you can try these steps.

    Step 1

    Reboot your computer. Hold shift to bring up the grub screen (if it doesn’t appear automatically). Press E at the grub prompt to edit the grub screen.

    Step 2

    Find the line starting with linux, change the ro to rw and append init=/bin/bash at the end of that line.

    Change ro to rw and add init=/bin/bash at the end of this line

    Step 3

    Press ctrl-x to save your changes and boot.

    Now you are booting into the Linux kernel with read and write permissions, and instead of going to a graphical user interface, you’ll use the bash shell.

    In other words, your system will boot up to a passwordless root shell.

    Step 4

    Type in the passwd command with your username. If you don’t know the username, check with ls /home command (as mentioned in method 1).

    Set your new password.

    Once you’ve set the new password, exit the terminal. Just type reboot in the terminal or use the shutdown command.

    Your password should be changed now.

    If resetting Ubuntu passwords is this easy, isn’t this a security risk?

    That’s a fair question. One of the main advantages of Linux over Windows is its security. But if “anyone” can reset the password, how come Ubuntu or other Linux distributions can be considered secure?

    Let me explain a few things here. The main security risk is if someone hacks into your account from a remote location via the internet. That’s not happening here.

    If anyone has physical access to your computer, the data in your computer is already at risk. Unless the entire disk is encrypted, anyone can “steal” your data using a live USB without even entering your installed operating system.

    By default, Ubuntu doesn’t have a root password and the root account is locked. The user account you set up while installing Ubuntu is included as an admin with sudo rights. But that doesn’t mean that you are root.

    This lack of root password is a deliberate feature The “advanced options for Ubuntu” in the boot menu allow you to perform some specific root-related tasks from the “root shell prompt”. This is why you’re able to reset the Ubuntu password through this method.

    If you want to make your system more secure, you can either encrypt the disk (to save your data) or setup a password for root user in Ubuntu.

    Bonus Tip: Handling the possible keyring issue after changing password

    There is a keyring feature in Ubuntu that is used for keeping passwords locked and safe.

    When you reset the forgotten password, the keyring remains unlocked and you may see an error message like this.

    Open the Passwords and Keys application and here, delete the Login passwords.

    When you try to use Google Chrome again in Ubuntu, it will ask you to create a new keyring. Use the new login password as the keyring password.

    Did it help you?

    I hope I made things clear about resetting forgotten passwords in Ubuntu.

    Did this quick tip help you recover your admin password? Do share in the comments below.

    Like what you read? Please share it with others.

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