How to Upgrade Ubuntu Safely: Complete Step-by-Step Guide for Beginners and Advanced Users

1. Preparation Before Upgrading

Before upgrading Ubuntu, several important preparations are required. Skipping these steps can increase the risk of errors during the upgrade process or even result in data loss. This section introduces essential steps to ensure system stability and safety.

System Backup Is Essential

Although Ubuntu upgrades are generally safe, creating a backup in advance is extremely important in case of unexpected errors or failures.

There are several backup methods available, and the following options are especially beginner-friendly:

• Copy important files to an external HDD or USB flash drive
• Back up the entire home directory using the rsync command
• Use disk image backup tools such as Clonezilla

An example of backing up via the command line is shown below:

rsync -a --progress /home/your-username /media/backup-drive/

Always take thorough precautions to protect your data.

Update the System to the Latest State

To ensure a smooth Ubuntu upgrade, your current system must be fully up to date. Use the following commands to update all packages:

sudo apt update
sudo apt upgrade
sudo apt dist-upgrade

dist-upgrade includes upgrades that involve dependency changes, making it essential before a version upgrade.

Remove Unnecessary Packages

Leftover unnecessary packages may cause errors during the upgrade. Use the following command to clean up your system:

sudo apt autoremove

It is also recommended to clear cached files to free up disk space and improve safety during the upgrade.

sudo apt clean

These steps complete the essential preparations before upgrading Ubuntu. Proper backups and system maintenance allow you to upgrade with confidence.

2. Upgrade Methods

There are two main ways to upgrade Ubuntu: using the GUI (Graphical User Interface) or using the command line (terminal). This section explains both methods with detailed steps and key points.

Upgrading via GUI (Recommended for Beginners)

If you are using the Ubuntu desktop edition, upgrading via the GUI is the most intuitive and safest option.

Step 1: Check Update Settings

Open “Software & Updates” and go to the “Updates” tab. Ensure that “Notify me of a new Ubuntu version” is set to either “For any new version” or “For long-term support versions.”

Step 2: Launch Update Manager

Start “Software Updater.” If a new version is available, a notification will appear.

Tip: Upgrades from one LTS version to the next LTS version may only appear after the first point release (.1) of the new LTS.

Step 3: Perform the Upgrade

Click the “Upgrade” button and follow the on-screen instructions. Multiple confirmation dialogs will appear—review each carefully. Ensure that the system power is not interrupted during the process.

Upgrading via Command Line (For Intermediate and Advanced Users)

For server environments or users who want more control and visibility, upgrading via the command line is recommended.

Step 1: Install Required Packages

First, ensure that the upgrade tool is installed:

sudo apt install update-manager-core

Step 2: Check the Configuration File

Edit the /etc/update-manager/release-upgrades file and confirm that the Prompt= value is set correctly:

• For regular releases: Prompt=normal
• For LTS releases only: Prompt=lts

sudo nano /etc/update-manager/release-upgrades

Step 3: Start the Upgrade

Run the following command to begin the upgrade:

sudo do-release-upgrade

This command upgrades your system to the next supported Ubuntu version. You may be prompted multiple times during the process—read each message carefully before proceeding.

Hint: If upgrading via SSH on a server, consider using options such as -d or -f DistUpgradeViewNonInteractive.

The upgrade process typically takes between 30 minutes and 1 hour, depending on your environment. After completion, you may be prompted to reboot the system.

3. Important Notes During the Upgrade

Although Ubuntu upgrades are generally safe, unexpected issues can still occur. This section explains common problems, how to handle them, and key decision points during the upgrade.

How to Handle Error Messages

You may encounter error messages such as the following during the upgrade:

Example 1: “Unable to fetch some archives, maybe run apt-get update or try with –fix-missing?”

This indicates that some packages could not be downloaded. Try the following command:

sudo apt update --fix-missing

In most cases, retrying the upgrade resolves the issue.

Example 2: “dpkg was interrupted, you must manually run ‘sudo dpkg –configure -a’”

This means the installation process was interrupted. Attempt recovery with:

sudo dpkg --configure -a

Then run sudo apt upgrade again to check the status.

Choosing How to Handle Configuration Files

During the upgrade, you may be asked whether to replace configuration files such as /etc/default/grub or /etc/ssh/sshd_config with newer versions.

Typical options include:

• Keep the current configuration file
• Install the new version
• Compare differences (press d to view diff)

Which Should You Choose?

• If you have not customized the settings → Install the new version
• If you have custom configurations → Keep the current version

You can always manually compare and adjust configuration files later, so reviewing differences carefully is recommended.

Avoid Power and Network Issues During the Upgrade

If power or network connectivity is lost during the upgrade, the system may become unstable. Pay special attention to the following:

• Keep the AC adapter connected (especially on laptops)
• Ensure a stable internet connection
• Allocate sufficient uninterrupted time for the upgrade

By following these precautions, you can upgrade Ubuntu safely and reliably.

4. Post-Upgrade Checks

Even after a successful Ubuntu upgrade, performing several checks and adjustments helps ensure long-term system stability and comfort. This section summarizes recommended post-upgrade tasks.

Verify the System Version

Confirm that the upgrade was successful by checking the system version:

lsb_release -a

Example output:

Distributor ID: Ubuntu
Description:    Ubuntu 24.04 LTS
Release:        24.04
Codename:       noble

If the target version is displayed, the upgrade was successful.

Remove Unnecessary Packages Again

After upgrading, unused packages and dependencies from the old version may remain. Clean them up using:

sudo apt autoremove
sudo apt clean

This frees disk space and improves system stability.

Check Japanese Input and Locale Settings

After upgrading, Japanese input methods (especially IBus or Fcitx) may stop working. If Japanese input is unavailable, reconfigure it as follows:

If Using Fcitx:

sudo apt install fcitx-mozc
im-config -n fcitx

Log out or reboot to enable the input method.

Reconfigure Locale Settings:

sudo dpkg-reconfigure locales

This is useful if the system language has reverted to English.

Check Third-Party Applications

Upgrading Ubuntu may affect PPAs (Personal Package Archives) and Snap applications. Verify the following:

• Frequently used applications launch correctly
• PPAs have not been disabled (re-add if necessary)
• Snap auto-update settings remain intact

To re-enable PPAs, check /etc/apt/sources.list.d/ and re-add or re-authenticate as needed.

These are the essential checks after upgrading Ubuntu. If everything works correctly, you can safely resume daily use.

5. Frequently Asked Questions (FAQ)

This section answers common questions about Ubuntu upgrades to help both new and experienced users.

Q1. How long does an Ubuntu upgrade take?

A1. It typically takes 30 minutes to 1 hour, depending on your hardware and internet speed.
Upgrading across multiple versions (e.g., 18.04 → 22.04) or using low-spec hardware may take longer. Ensure you have enough time before starting.

Q2. What should I do if the power goes out during the upgrade?

A2. Power loss can corrupt system files. Try the following steps:

1. Boot into recovery mode (GRUB menu → “Advanced options” → “Recovery mode”)
2. Run the following commands:

sudo dpkg --configure -a
sudo apt update
sudo apt upgrade

3. If the system remains unstable, restore from backup or boot using a Live USB to recover data.

Q3. What is the difference between LTS and regular releases?

A3. LTS (Long Term Support) releases provide five years of support and prioritize stability. Regular releases introduce new features more quickly but are supported for only nine months.

• Choose LTS if: You value stability, use servers, or rely on Ubuntu for work
• Choose regular releases if: You want the latest features and are an advanced user or developer

Q4. Can I upgrade directly from an old version to the latest release?

A4. Generally, upgrades must be performed sequentially, one version at a time. For example, upgrading directly from 18.04 LTS to 22.04 LTS usually requires passing through 20.04 LTS.
However, Ubuntu officially supports some LTS-to-LTS upgrades via do-release-upgrade.

Q5. Can I roll back after an upgrade if problems occur?

A5. Ubuntu does not provide a built-in rollback feature like Windows. This makes pre-upgrade backups extremely important.
To revert, you must perform a clean installation of the previous version using its ISO image and restore your data from backup.

This FAQ is based on real user experiences. Resolving common concerns in advance helps ensure a smooth and stress-free Ubuntu upgrade.