The hostname identifies your server on a network and appears in shell prompts, log files, and monitoring dashboards. Ubuntu 26.04 LTS uses hostnamectl — a systemd utility — to view and change the hostname persistently without a reboot.

Tested and valid on:

  • Ubuntu 26.04 LTS

Prerequisites

  • Ubuntu 26.04 LTS server
  • A user with sudo privileges

Step 1 – Check the Current Hostname

Display the full hostname configuration:

hostnamectl

Step 2 – Set a New Static Hostname

Replace new-hostname with your desired name (lowercase letters, digits, and hyphens only):

sudo hostnamectl set-hostname new-hostname

Step 3 – Update /etc/hosts

Ensure the new hostname resolves locally to prevent sudo delays:

sudo nano /etc/hosts

Update the line with 127.0.1.1 to match the new hostname:

127.0.1.1   new-hostname

Step 4 – Set a Pretty Hostname (optional)

A pretty hostname can include spaces and special characters for display purposes:

sudo hostnamectl set-hostname "My Production Server" --pretty

Step 5 – Verify the Change

Confirm the new hostname is set:

hostnamectl
hostname
uname -n

Open a new shell session to see the updated prompt.

Step 6 – Set Hostname in Cloud Environments

On cloud instances (AWS, GCP, Azure), cloud-init may reset the hostname on reboot. Disable this behaviour:

sudo nano /etc/cloud/cloud.cfg

Set or confirm:

preserve_hostname: true

Conclusion

Your Ubuntu 26.04 LTS server now has a persistent hostname that survives reboots. Update DNS records if this server is addressed by a domain name, and inform any monitoring systems of the change.