How to change Hostname in Linux?

Introduction: The Importance of the Hostname in Linux

The hostname in Linux serves as a unique identifier for a device on a network. It plays a crucial role in network communication and system administration, including the process of how to change hostname in Linux. When devices connect to a network, the hostname helps distinguish one system from another, allowing for efficient data transfer and identification. Additionally, the hostname is used by various services and applications for network configuration, security, and troubleshooting purposes.

Having a meaningful and descriptive hostname is particularly useful in larger networks or environments where multiple devices are interconnected. A well-chosen hostname can provide valuable information about the device's purpose, location, or owner, making it easier to manage and administer the network.

Best Practices for Choosing a Hostname

When selecting a hostname for your Linux system, following some best practices is advisable to ensure a practical and secure choice. Here are a few guidelines:

1. Avoid Sensitive Information:
   • Refrain from including sensitive information in the hostname, such as personal details or confidential data.
   • This helps minimize the risk of inadvertently exposing sensitive information to external parties.
2. Use Descriptive Names:
   • Choose a hostname that provides meaningful information about the device's purpose, location, or role.
   • This makes identifying and managing the device easier within a network environment.
3. Stick to Alphanumeric Characters:
   • Limit the hostname to alphanumeric characters (letters and numbers) and hyphens ("-").
   • Avoid using special characters or spaces, as they can cause issues with network protocols or applications that interact with the hostname.
4. Keep it Concise:
   • Opt for a concise hostname that is easy to remember and type.
   • Long or complex hostnames can be prone to typos or errors, which can cause difficulties when managing the system.
5. Consider FQDN:
   • If your Linux system is part of a domain or larger network, you might want to choose a Fully Qualified Domain Name (FQDN) as the hostname.
   • An FQDN consists of the host and domain names, separated by a dot.
   • This can enhance network management and allow for easier DNS resolution.

How To Change Hostname in Linux?

The hostname in Linux refers to the name assigned to a computer or device on a network. It is a unique identifier that helps distinguish one system from another. Changing the hostname in Linux can be necessary for various reasons, such as personalizing the system or resolving network conflicts. In this article, we will explore different methods on how to change hostname in Linux

Option 1. Using the hostnamectl Command

One of the simplest and most common ways to change the hostname in Linux is by using the hostnamectl command. This command is available in most modern Linux distributions and provides a straightforward method for managing the system's hostname.

Here's a step-by-step guide on how to change the hostname using the hostnamectl command:

1. Open a terminal or command prompt on your Linux system.
2. Use the following command to check the current hostname:
   This command will display information about the current system hostname.
3. To change the hostname, use the set-hostname option followed by the desired hostname. For example, to change the hostname to mylinuxmachine, use the following command:
   Replace mylinuxmachine with your preferred hostname.
4. After executing the command, you need to update the hosts file. Open the host's file using a text editor such as nano or vim:
   Locate the line that contains the old hostname and replace it with the new hostname.
5. Save the changes and exit the text editor.
6. Finally, update the hostname by restarting the systemd-hostnamed service:
   Alternatively, you can also reboot the system for the changes to take effect.

By following these steps, you should be able to change the hostname using the hostnamectl command.

Option 2. Using the Network Manager Text User Interface (nmtui)

Another method to change the hostname in Linux is by utilizing the Network Manager Text User Interface (nmtui). This approach is especially useful for systems with a graphical interface, where accessing the terminal might not be as convenient.

To change the hostname using nmtui, perform the following steps:

1. Open a terminal or command prompt on your Linux system.
2. Type the following command to launch the Network Manager Text User Interface:
   This command will open the nmtui interface, allowing you to manage network settings.
3. Use the arrow keys to navigate to the "Edit a connection" option and press Enter.
4. Select the network connection you want to modify and press Enter.
5. Navigate to the "IPv4 CONFIGURATION" section and press Enter.
6. Locate the "Hostname" field and enter the desired hostname.
7. Press Tab to move the cursor to the "OK" button and press Enter.
8. Exit the nmtui interface.

After completing these steps, the system should have the updated hostname. It's important to note that changes made through nmtui may require a system reboot to take effect.

Option 3. Edit the Configuration Files

For advanced users or those who prefer manual configuration, editing the relevant configuration files is another viable option to change the hostname in Linux. This method requires modifying specific files directly, so caution is advised to avoid any unintended changes that may disrupt the system.

Follow the steps below to change the hostname by editing the configuration files:

1. Open a terminal or command prompt on your Linux system.
2. Use a text editor such as nano or vim to open the main hostname configuration file:

3. Within the file, replace the current hostname with the desired hostname.
4. Save the changes and exit the text editor.
5. Next, open the hosts file:

6. Locate the line that contains the old hostname and update it with the new hostname.
7. Save the changes and exit the text editor.
8. Restart the system or execute the following command to apply the new hostname without rebooting:
   Replace <new_hostname> with the desired hostname.

By following these steps and editing the appropriate configuration files, you can successfully change the hostname in Linux.

How to Change Hostname in Linux Without Rebooting

In some cases, it may be desirable to change the hostname without rebooting the system. Although rebooting is the most reliable way to ensure the new hostname is fully applied, alternative methods allow you to change the hostname without a restart.

One method involves executing the following command after changing the hostname:

This command restarts the systemd-hostnamed service, which will apply the new hostname. However, it's worth noting that this method may not work consistently across all Linux distributions or configurations. Rebooting the system remains the recommended approach to ensure all services and applications recognize the new hostname correctly.

Another option to change the hostname without rebooting is by creating a temporary network namespace. This method is more complex and requires advanced knowledge of Linux networking. It involves using commands such as ip netns add, ip netns exec, and ip netns delete to create a separate network namespace where the new hostname can be applied temporarily. However, this approach is beyond the scope of this article and is not recommended for beginners.