This article shows you how to change the root account password of a Linux system either knowing the current one or not knowing this information.
Steps
Method 1 of 2: Knowing the Current Password
Step 1. Open a "Terminal" window
Using most Linux distributions just press the hotkey combination Ctrl + Alt + T. This will bring up a new "Terminal" window.
If you are not using a Linux distribution with a graphical interface, it means that you already have the command prompt available and you can proceed directly to the next step of the method
Step 2. Type the command su into the "Terminal" window and press the Enter key
A new prompt will appear with the following Password:.
Step 3. Type the current root user's password and press the Enter key
If the password entered is correct, you will be automatically returned to the command prompt of the "Terminal" window with the access rights of the root account.
- If the password entered is wrong, run the su command again and try again.
- Remember that passwords are case-sensitive, meaning they differentiate between uppercase and lowercase letters.
Step 4. Type the command passwd and press the Enter key
A new command line will be displayed with the following text Enter new UNIX password:.
Step 5. Type the new password you want to set and press the Enter key
For security reasons, no characters will appear on the screen while typing the password.
Step 6. Retype the password you just entered and press the Enter key
You will see a text message similar to the following "password updated successfully".
Step 7. Type the command exit and press the Enter key
This will log you out of the root account and the "Terminal" window will close.
Method 2 of 2: Without Knowing the Current Password
Step 1. Restart your computer
Step 2. Press the E key when the "Grub" menu appears on the screen
The "Grub" menu will appear on the screen as soon as the computer starts the boot process. In most cases it will only remain visible for a few moments.
- If you don't press the E key before the "Grub" menu disappears from the screen, you will need to restart your system and try again.
- This procedure works for most popular Linux distributions (Ubuntu, CentOS 7, Debian). However, there are many other versions of Linux some easier to use than others, so if you are unable to boot the system in "single user" mode, refer to the website of the distribution in use for more information on how to proceed.
Step 3. Scroll through the list to find the line of text that begins with the following wording linux / boot
To move the text cursor use the ↑ and ↓ keys on the keyboard. In order to start the system in "single user" mode, the indicated line of text must be changed.
Using the CentOS version of Linux and some other distributions you will need to search for the line of text starting with the word linux16 instead of linux
Step 4. Move the text cursor to the end of the indicated line
Use the →, ←, ↑ and ↓ keys to position the cursor exactly after the final characters ro.
Step 5. Type the following text init = / bin / bash after the characters ro
When you are done editing, the indicated line of text should look like this:
ro init = / bin / bash
-
Note that the characters
ro
and the text
init = / bin / bash
- they are separated by a blank space.
Step 6. Press the key combination Ctrl + X
This will instruct the operating system to start the command prompt in "single user" mode with the privileges of the root account.
Step 7. Type the following text mount –o remount, rw / as soon as the command prompt appears and press the Enter key
This will "mount" the entire file system, but in "read / write" mode.
Step 8. Type the command passwd and press the Enter key
Since the system is active in "single user" mode with the access rights of the root account, you will not need to re-enter the admin password to run the passwd command
Step 9. Type the new password you want to set and press the Enter key
For security reasons, no characters will appear on the screen while typing the password.
Step 10. Retype the password you just entered and press the Enter key
As soon as the operating system confirms that you have entered the same password, you will see a text message similar to the following "password updated successfully".
Step 11. Type the reboot -f command and press the Enter key
This will cause the system to boot normally.
Advice
- The security password should be at least 8 characters long and should contain a combination of upper and lower case letters, numbers and symbols.
- To change the login password of another user account, run the su command to get the root account rights, then type the passwd command.
