How to Change Root Password on Centos 7

As a technical blogger, it is essential to understand the importance of securing your Linux server. One way to increase security measures is by changing root password on Centos 7. Root is the ultimate account in Linux, with access to all files and system privileges. Therefore, it is important to have a strong password that is hard for unauthorized users to guess or hack. In this blog post, we will guide you through various methods and steps to change root password on Centos 7.

Video Tutorial:

What’s Needed

Before we start, there are some prerequisites for changing the root password on Centos 7. You must have access to the following:

1. A Linux server running Centos 7
2. A user account with sudo privileges
3. A stable Internet connection

What Requires Your Focus?

Changing root password on Centos 7 requires attention to detail to ensure security and prevent any unintended consequences. You should focus on:

1. Creating a strong password that is long and complex, including alphanumeric characters and special characters.
2. Remembering the password or store it securely.
3. Verifying the new password after changing it to ensure it is entered correctly.
4. Checking the new password functions correctly, in case any errors come up.

Methods to Change Root Password on Centos 7

Here are several methods to change root password on Centos 7.

Method 1: Changing the Root Password Using the passwd Command

This method involves using the passwd command in the CentOS terminal to change the root password. Follow the following steps:

1. Use the su command to switch to the root user:

su

2. Enter the current password for the root user.

3. Type the passwd command, followed by the new password:

passwd

4. Enter the new password when prompted, ensuring that it is complex and secure.

5. The system will prompt you to retype the new password to confirm it.

6. Type the new password once more to confirm.

Pros

– This method is easy to remember.
– You do not require sophisticated software to change the password.

Cons

– It is vulnerable to dictionary attacks.

Method 2: Changing the password Using Gnome Desktop

This method requires a graphical user interface (GUI). You can use the following steps:

1. Launch gnome control center.

2. Select “Users.”

3. Click on the user whose password you want to update.

4. Click on “Unlock” to change the attributes.

5. Enter your user password.

6. The next step is to click on the “Password” section.

7. At the top right corner of the Account Details window, click "Change".

8. You’ll be prompted to enter your current password and then put in a new password two times.

9. Once done, click “Change” to Confirm.

Pros

– This method does not require the use of terminal commands.
– It is easy to use for beginners.

Cons

– It only work for Graphical interface users.
– It is not effective for big systems.

Method 3: Changing the Root Password Using System Rescue Mode

Using system rescue mode is a more technical method, mainly for users who have lost access to root account due to forgotten passwords. You can use the following steps:

1. Boot into rescue mode. Connect to the system for which the password must be changed, then reboot the server and interrupt the boot process.

2. At the Grub boot menu, select the “CentOS Linux Rescue” option.

3. Press Enter to begin the rescue mode startup.

4. Choose your language.

5. Choose your keyboard layout.

6. When prompted for the root password, you’ll see an option that says “Continue”, click on it.

7. Once the system is booted, you will see your system information on the screen. Open shell terminal.

8. Type the command: chroot /mnt/sysimage.

9. Type the command: passwd root.

10. Enter the new password.

Pros

– This method enables you to reset the root password without using sudo powers.

Cons

– You must have technical knowledge to do this.
– The method involves the use of multiple steps.

Why Can’t I Change Root Password on Centos 7

Here are some reasons why you can cannot change root password:

1. You are not logged in as a current user when using Terminal.
2. The legacy system that uses NIS or LDAP, which does not allow local member password modification.
3. The password is locked as part of the company IT policy.

Fixes:

1. Ensure that you have sudo powers before resetting the password in Terminal.
2. Check your company’s IT policy and ensure that it does allows password modification.

Implications and Recommendations

Changing your root password on CentOS 7 limits the risk of unauthorized access to your Linux server. A strong password that can’t be easily predicted or guessed is vital. Here are some recommendations:

1. Password Length: Use passwords that are at least 12 characters long.

2. Password Complexity: Use various character classes, including uppercase and lowercase letters, symbols, and digits.

3. Password Storage: Use password managers like 1Password and LastPass to store your passwords securely.

5 FAQs About Changing Root Password on Centos 7

Q1: How Do You Reset a Forgotten Root Password on Centos 7?

A: Boot the server in rescue mode, and use the passwd command.

Q2: Can I Change the Root Password for Another User on Centos 7?

A: No. But the admin can reset the password for another user.

Q3: What is Root Account?

A: Root is a "superuser" account that oversees all administrative functions on Linux systems.

Q4: Can I Reuse an Old Password to New Password?

A: No. The new password must be new.

Q5: Can a Password Contain Spaces?

A: No. Linux does not allow you to store passwords with spaces.

In Conclusion

In conclusion, changing your root password on Centos 7 is a fundamental task that ensures that your server is secure and reduces chances of unauthorized access. The above methods are easy to use and employ. Still, always keep in mind that the new passwords must be secure, complex and preventative to prevent security breaches.