Upgrade Ubuntu 24.04 to 26.04 LTS: Complete Step-by-Step Guide

Ubuntu 26.04 LTS, codenamed Resolute Raccoon, released on April 23, 2026. If you manage Ubuntu servers on 24.04, now is the time to prepare. The direct upgrade path from 24.04 to 26.04 opens on August 6, 2026 with the 26.04.1 point release. This guide walks through how to upgrade Ubuntu 24.04 to 26.04 properly, covering preparation, the upgrade command, common failure points, and what to verify afterward. Skipping preparation is how upgrades break at the worst possible time.

What Changed in Ubuntu 26.04 LTS

Before deciding when to upgrade Ubuntu 24.04 to 26.04, understand what is changing. Several things affect server workloads directly. According to the LinuxConfig Ubuntu 26.04 feature guide, key changes include:

• Linux kernel 7.0 — first LTS release to ship the 7.x kernel series
• Rust-based core utilities — sudo, coreutils, and system tools now have Rust replacements
• systemd 259 with mandatory cgroup v2 — cgroup v1 is removed entirely
• Dracut replaces initramfs-tools as the default initramfs generator
• APT 3 with apt-key removed and updated keyring management
• Post-quantum cryptography defaults in OpenSSH and OpenSSL
• Ubuntu 26.04 LTS receives security support until April 2036 with Ubuntu Pro

For servers, the mandatory cgroup v2 change is the most likely to cause issues. If you run Docker, LXC, or any container runtime, test compatibility in staging before upgrading production systems. The Canonical Ubuntu 26.04 release notes have the full list of removed and deprecated packages worth checking against your stack.

Upgrade Path: When to Do It

The direct upgrade from 24.04 to 26.04 is not yet open. Canonical enables LTS-to-LTS upgrades only after the first point release. Ubuntu 26.04.1 is scheduled for August 6, 2026. That is the earliest safe date for production server upgrades through the standard do-release-upgrade tool.

You can upgrade right now from Ubuntu 25.10 to 26.04. You can also force an early upgrade from 24.04 for testing environments:

# Standard path (wait until August 6, 2026 for production)
sudo do-release-upgrade

# Force early upgrade from 24.04 (testing/dev only)
sudo do-release-upgrade -d

For production servers on 24.04, do not rush. Ubuntu 24.04 LTS has security support until April 2029. Wait for 26.04.1, test your stack in staging, then roll out in waves.

Step 1: Update Everything First

Upgrade failures usually trace back to three causes: the system was not fully updated, a PPA broke dependency resolution, or the machine was not rebooted after a kernel update. Fix all three before starting:

sudo apt update && sudo apt upgrade -y
sudo apt full-upgrade -y
sudo apt autoremove -y && sudo apt autoclean

# Reboot after any kernel update
sudo reboot

After rebooting, confirm the current kernel is running and fix any broken packages:

uname -r

sudo dpkg --configure -a
sudo apt install -f

# Check for held packages
sudo apt-mark showhold

If packages are held, review whether they can be released. Held packages that conflict with 26.04 dependencies will stop the upgrade partway through.

Step 2: Disable Third-Party PPAs

PPAs are the most common cause of failed Ubuntu upgrades. During the upgrade, do-release-upgrade disables them automatically. But if a PPA introduced conflicting packages, the upgrade can fail mid-process. Disable them first:

# List all enabled PPAs
grep -r "^deb " /etc/apt/sources.list.d/ | grep -v "archive.ubuntu.com"

# Disable all third-party PPAs
for ppa in /etc/apt/sources.list.d/*.list; do
    sudo mv "$ppa" "${ppa}.disabled"
done

sudo apt update

After the upgrade, re-enable PPAs one at a time after confirming they have Ubuntu 26.04 packages available.

Step 3: Check Disk Space

The upgrade downloads several gigabytes of packages. You need at least 15 GB free on the root partition. Check first:

df -h /

If space is low, clear the cache and remove old kernels:

sudo apt clean
sudo apt autoremove --purge
df -h /

If your root volume is on LVM, you can extend it without downtime before starting. Our LVM disk management guide walks through adding space to a live volume.

Step 4: Run do-release-upgrade

For remote servers, run the upgrade inside a screen or tmux session so a disconnection cannot interrupt it:

# Start a screen session
screen -S ubuntu-upgrade

# Install the upgrade tool
sudo apt install update-manager-core -y

# Verify release upgrade is set to lts
cat /etc/update-manager/release-upgrades

# Run the upgrade
sudo do-release-upgrade

If you disconnect during the upgrade, reattach with screen -r ubuntu-upgrade. When prompted about locally modified config files, review the diff carefully before accepting. For system files like sshd_config, accepting the package maintainer version is usually safer after saving your customisations first.

Step 5: Reboot and Verify

After the upgrade completes, reboot and verify:

sudo reboot

# Confirm the new Ubuntu version
lsb_release -a

# Confirm kernel 7.x is running
uname -r

# Check for failed services
systemctl --failed

# Run final update pass
sudo apt update && sudo apt upgrade -y
sudo apt autoremove -y

Some packages get held back during the release upgrade and only resolve cleanly after the first normal update pass. Always run apt upgrade again after confirming the system is stable.

Common Issues After the Upgrade

Three problems come up most often after this upgrade.

Container runtime failures: Docker and LXC may fail because cgroup v1 is removed in Ubuntu 26.04. Update Docker and verify it switches to cgroup v2:

sudo apt update && sudo apt install docker-ce -y
sudo systemctl restart docker
docker info | grep "Cgroup"

SSH configuration overwritten: The upgrade may replace your SSH config with the package default. Check that your settings survived:

diff /etc/ssh/sshd_config /etc/ssh/sshd_config.dpkg-old 2>/dev/null

PPA package conflicts: After re-enabling PPAs, run apt update and look for 404 errors. Disable any PPA that does not yet have 26.04 packages and wait for the maintainer to update.

After the upgrade, re-verify your server hardening configuration. Ubuntu 26.04 ships stronger defaults but your custom SSH, firewall, and sysctl settings still need review. Our Linux server hardening checklist covers every setting worth checking after a major OS upgrade.

Should Production Servers Upgrade Now?

Not yet. Wait for 26.04.1 on August 6, 2026. Test your full stack in staging first. The cgroup v2, kernel 7.0, and Rust utility changes are significant enough that a staged rollout is worth the wait. Ubuntu 24.04 LTS is fully supported until April 2029, so there is no pressure.

Conclusion

The process to upgrade Ubuntu 24.04 to 26.04 is straightforward when properly prepared. Update everything first, disable third-party PPAs, confirm disk space, run do-release-upgrade inside a screen session, reboot, and verify. The official upgrade path opens August 6, 2026. Use the next two months to test in staging and prepare your production fleet. Start that testing today while the release is current and documentation is fresh.