Upgrade Ubuntu Server 24.04 LTS to 26.04 LTS (Step-by-Step Guide)

How to Upgrade Ubuntu Server 24.04 LTS to Ubuntu Server 26.04 LTS

Upgrading to Ubuntu Server 26.04 LTS gives you access to the latest Long Term Support release, including updated packages, improved security, newer hardware support, and continued maintenance from Canonical. This guide explains how to upgrade an existing Ubuntu Server 24.04 LTS installation safely while minimizing downtime.

Before You Start
Always perform the upgrade during a maintenance window. Create a verified backup or snapshot of your server before making any changes.

System Requirements

  • Ubuntu Server 24.04 LTS
  • Stable Internet connection
  • Root or sudo privileges
  • At least 2 GB free disk space (more is recommended)
  • A recent backup or VM snapshot

Step 1 – Update Your Current System

Install all available updates before starting the release upgrade.

sudo apt update sudo apt upgrade -y sudo apt full-upgrade -y sudo apt autoremove -y sudo reboot

Reconnect to the server after it has restarted.


Step 2 – Verify the Current Ubuntu Version

lsb_release -a

The output should show Ubuntu Server 24.04 LTS.


Step 3 – Ensure the Upgrade Tool Is Installed

sudo apt install update-manager-core

Confirm that /etc/update-manager/release-upgrades contains:

Prompt=lts

Step 4 – Start the Release Upgrade

sudo do-release-upgrade

Follow the on-screen instructions. During the process you may be asked about configuration files. If you have not customized them, choosing the maintainer's version is usually appropriate. If you have made local changes, review each prompt carefully.


Step 5 – Reboot the Server

After the upgrade finishes, reboot the system.

sudo reboot

Step 6 – Verify the Upgrade

lsb_release -a uname -r hostnamectl

Confirm that the system reports Ubuntu Server 26.04 LTS.


Post-Upgrade Checklist

  • Install the latest updates
  • Verify SSH access
  • Check web server and database services
  • Confirm firewall rules (UFW or other)
  • Review system logs for errors
  • Restart application services if required
sudo apt update sudo apt upgrade -y

Common Issues

Upgrade Not Available

Make sure all packages are fully updated and that the release upgrader is configured to use LTS releases.

Insufficient Disk Space

Remove unnecessary packages and clear the APT cache before retrying the upgrade.

sudo apt autoremove sudo apt clean

Third-Party Repositories

Disable unsupported third-party repositories before upgrading, then re-enable them only after confirming compatibility with Ubuntu 26.04 LTS.


Best Practices

  • Create a backup or VM snapshot before upgrading.
  • Test the upgrade on a staging server before production.
  • Schedule the upgrade during a maintenance window.
  • Verify application compatibility in advance.
  • Review the official release notes before upgrading.

Conclusion

Upgrading from Ubuntu Server 24.04 LTS to Ubuntu Server 26.04 LTS is straightforward when your system is fully updated and prepared. By following the steps in this guide, you can reduce the risk of downtime and ensure a smooth transition to the latest Long Term Support release.


Related Articles

  • What's New in Ubuntu Server 26.04 LTS
  • Ubuntu Server 26.04 LTS Release Notes Explained
  • Breaking Changes in Ubuntu Server 26.04 LTS