How to Change Hostname on Ubuntu 26.04

Changing your hostname on Ubuntu 26.04 is a fundamental system administration task that identifies your machine on a network. Whether you’re setting up a new server, renaming a workstation, or organizing your home lab, this guide covers all the methods to hostname change Ubuntu 26.04 systems effectively, from quick command-line solutions to GUI approaches.

Software Requirements

Software Requirements and Linux Command Line Conventions

Category	Requirements, Conventions or Software Version Used
System	Ubuntu 26.04 Resolute Raccoon
Software	systemd (pre-installed), hostnamectl utility
Other	Privileged access to your Linux system as root or via the sudo command.
Conventions	# – requires given linux commands to be executed with root privileges either directly as a root user or by use of sudo command $ – requires given linux commands to be executed as a regular non-privileged user

Using hostnamectl to Change Hostname on Ubuntu 26.04

The hostnamectl command is the recommended method to hostname change Ubuntu 26.04 systems. This systemd utility handles all hostname types and persists changes automatically across reboots.

Understanding Hostname Types

Before changing your hostname, it’s helpful to understand that Linux systems maintain three different hostname types:

• Static hostname: The traditional hostname stored in /etc/hostname. This is the main system identifier.
• Pretty hostname: A free-form UTF-8 hostname for presentation to users (can include spaces and special characters).
• Transient hostname: A dynamic hostname assigned by DHCP or mDNS at runtime.

Step-by-Step Instructions

1. Check your current hostname: First, view your existing hostname configuration by running:

   $ hostnamectl

   This displays all three hostname types along with other system information like machine ID, boot ID, operating system, and kernel version. For example, if your current hostname is linuxconfig, you’ll see that in the Static hostname field.

   

2. Set the new hostname: Use the set-hostname subcommand to change your hostname:

   $ sudo hostnamectl set-hostname webserver

   Replace webserver with your desired hostname. This command updates the static hostname immediately without requiring a reboot.

3. Update the /etc/hosts file: Although hostnamectl updates /etc/hostname, you should also update /etc/hosts to prevent potential issues with local hostname resolution:

   $ sudo nano /etc/hosts

   Locate the line containing your old hostname (e.g., linuxconfig) and replace it with the new one. The file should look similar to:

   127.0.0.1       localhost
   127.0.1.1       webserver

   

4. Verify the change: Confirm your new hostname is active:

   $ hostnamectl

Setting a Pretty Hostname

If you want a human-friendly hostname with spaces or special characters, use the --pretty flag:

$ sudo hostnamectl set-hostname "Web Server" --pretty

This sets the pretty hostname while keeping the static hostname unchanged. You can view it with:

$ hostnamectl --pretty

GUI Method for Ubuntu Desktop

Ubuntu 26.04 desktop users can change the hostname through GNOME Settings without touching the command line.

1. Open Settings: Click the system menu in the top-right corner and select “Settings,” or search for “Settings” in the Activities overview.
2. Navigate to System: In the Settings window, click on “System” in the left sidebar, then select “About.”
3. Change Device Name: Click on “Device Name” to edit it. Enter your new hostname and confirm the change.

The GUI method sets the pretty hostname, which GNOME displays as the device name. For comprehensive hostname configuration including static hostname changes, use the command-line methods described above.

Hostname Naming Conventions

When choosing a new hostname, follow these guidelines to avoid issues:

Hostname Naming Rules and Guidelines

Rule	Description	Example
Allowed characters	Use only lowercase letters (a-z), numbers (0-9), and hyphens (-)	web-server-01 ✓
Start character	Must start with a letter, not a number or hyphen	server1 ✓ / 1server ✗
End character	Must not end with a hyphen	web-server ✓ / web-server- ✗
Maximum length	Keep under 63 characters (DNS limit)	webserver ✓
No underscores	Avoid underscores. Violates RFC 1123 and may cause DNS issues	web-server ✓ / web_server ✗

Conclusion

You have learned how to hostname change Ubuntu 26.04 systems using the recommended hostnamectl command and the GNOME Settings GUI for desktop users. Regardless of which method you choose, remember to update both /etc/hostname and /etc/hosts to ensure consistent hostname resolution across your system.

Frequently Asked Questions

1. Do I need to reboot after changing the hostname on Ubuntu 26.04? No, a reboot is not required when using hostnamectl set-hostname. The change takes effect immediately. However, you may need to open a new terminal session or log out and back in to see the updated hostname in your shell prompt. Some running services may need to be restarted to pick up the new hostname.
2. What is the difference between static, pretty, and transient hostnames? The static hostname is your permanent system identifier stored in /etc/hostname. The pretty hostname is a descriptive name that can include spaces and special characters, used for display purposes. The transient hostname is temporary and can be set dynamically by DHCP or network services. For most uses, you only need to worry about the static hostname.
3. Why should I update /etc/hosts after changing the hostname? The /etc/hosts file maps hostnames to IP addresses for local resolution. If you don’t update it, some applications may fail to resolve your hostname locally, potentially causing delays or errors. Always update the 127.0.1.1 line to match your new hostname.
4. Can I use special characters or spaces in my hostname? The static hostname should only contain lowercase letters, numbers, and hyphens. However, you can set a “pretty hostname” with spaces and special characters using hostnamectl set-hostname "My Server" --pretty. The pretty hostname is used for display purposes only and doesn’t affect network identification.
5. How do I change the hostname on Ubuntu Server without a GUI? Use the command sudo hostnamectl set-hostname webserver followed by editing /etc/hosts to update the 127.0.1.1 entry. This is the same method used on desktop systems and doesn’t require any graphical interface.