Ubuntu Focal Fossa (20.04 LTS) is a long-term support release that offers a stable and reliable platform for various computing needs. Keeping your system updated is crucial for security, performance, and access to the latest features. This guide delves into the comprehensive process of installing updates from Ubuntu Focal, covering both graphical and command-line methods, and highlighting best practices for a smooth and secure update experience.
Understanding Ubuntu Updates
Ubuntu’s update mechanism is designed to be robust and user-friendly. It primarily relies on a package management system called APT (Advanced Packaging Tool). APT handles the downloading, installation, and management of software packages on your system. Updates can range from minor security patches to significant software version upgrades.

Types of Updates
There are generally two main categories of updates you’ll encounter:
- Security Updates: These are critical patches released to address vulnerabilities discovered in the operating system or installed software. They are paramount for protecting your system from malicious attacks.
- Software Updates: These include new versions of applications, libraries, and system components. They often introduce new features, improve existing functionality, and fix bugs.
Long-Term Support (LTS) Releases
Ubuntu Focal Fossa is an LTS release, meaning it receives standard security and maintenance updates for five years from its initial release. This makes it an excellent choice for users who prioritize stability and don’t want to upgrade their operating system frequently. For enterprise environments, extended security maintenance (ESM) is available for an additional five years, bringing the total support to ten years.
Sources of Updates
Updates are typically retrieved from official Ubuntu repositories. These are servers hosted by Canonical (the company behind Ubuntu) and its mirrors worldwide, ensuring fast and reliable access to software. You can also configure your system to use third-party repositories, often referred to as PPAs (Personal Package Archives), although these should be used with caution as they are not officially supported by Ubuntu.
Graphical Update Methods
For users who prefer a visual interface, Ubuntu provides intuitive graphical tools to manage system updates. These methods are straightforward and suitable for most users.
Using the Software Updater
The Software Updater application is the primary graphical tool for managing updates in Ubuntu. It scans your system for available updates and presents them in an organized list.
Launching Software Updater
- Open the Activities overview by clicking the “Activities” button in the top-left corner of your screen or by pressing the
Superkey (usually the Windows key). - Type “Software Updater” in the search bar.
- Click on the Software Updater icon when it appears.
Performing an Update
- Once Software Updater launches, it will automatically check for available updates.
- If updates are found, you will see a list of packages that can be updated. You can review this list to see what is being updated.
- Click the Install Now button to begin the update process.
- You may be prompted to enter your user password to authorize the installation.
- The updater will download and install the selected updates. This process can take some time depending on the number and size of the updates and your internet connection speed.
- After the updates are installed, you might be prompted to restart your computer to apply all changes. It’s generally recommended to restart after significant updates.
Managing Additional Software Sources
The Software & Updates application is a companion tool to Software Updater that allows you to manage your software sources.
- Open the Activities overview.
- Type “Software & Updates” and launch the application.
- In the Ubuntu Software tab, you can enable or disable official repositories and select the download server closest to your location for faster downloads.
- The Other Software tab is where you can add or remove PPAs. Be cautious when adding PPAs, as they can sometimes cause system instability or introduce security risks.
Using the Software Center
While primarily for installing new applications, the Ubuntu Software application (also known as Snap Store or GNOME Software) also indicates when updates are available for installed applications, especially those installed as snaps.
- Open the Activities overview.
- Type “Software” and launch the Ubuntu Software application.
- Click on the Updates tab (usually represented by a downward-pointing arrow or a circular arrow icon).
- Any available updates for applications installed through the Software Center will be listed here.
- Click the Update button next to each application you wish to update.
Command-Line Update Methods
For users who are comfortable with the terminal, command-line methods offer greater control and are often faster for experienced users. These methods are also essential for server environments where a graphical interface may not be present.
APT: The Core of Ubuntu Package Management
APT is a powerful command-line tool that underlies Ubuntu’s update process. It allows you to interact with software repositories to install, remove, and update packages.
Updating the Package List
Before installing any updates, it’s crucial to refresh your system’s local list of available packages. This ensures that APT knows about the latest versions of software available in the repositories.

- Open a terminal window. You can do this by pressing
Ctrl + Alt + T. - Execute the following command:
bash
sudo apt update
sudo(superuser do) is used to execute commands with administrative privileges, which are required for package management.apt updatedownloads package information from all configured sources.
Upgrading Installed Packages
Once the package list is updated, you can upgrade all installed packages to their latest available versions.
- After running
sudo apt update, execute the following command:
bash
sudo apt upgrade
apt upgradeinstalls newer versions of all packages currently installed on the system from the sources enumerated in/etc/apt/sources.list. It will not remove packages or install new packages that are not already installed.- APT will present a list of packages to be upgraded and ask for confirmation before proceeding. Type
Yand press Enter to continue.
Full System Upgrade (Dist-Upgrade)
The apt upgrade command is generally safe, but it avoids removing packages or installing new ones to resolve dependencies. For more comprehensive upgrades that might involve installing new dependencies or removing conflicting packages, apt dist-upgrade is used. This is often necessary when upgrading between different minor versions of Ubuntu or when significant package changes are introduced.
- After running
sudo apt update, execute:
bash
sudo apt dist-upgrade
apt dist-upgradeperforms the same function asupgradebut will also intelligently handle changing dependencies with new versions of packages;apt upgradewill not perform these actions.- This command can be more aggressive in resolving dependencies and might lead to the removal of some packages if they conflict with newly installed ones. Always review the list of changes carefully before confirming.
Removing Unused Packages
After performing upgrades, you might have packages that are no longer needed. These can be automatically removed to free up disk space.
- Execute the following command:
bash
sudo apt autoremove
apt autoremoveremoves packages that were automatically installed to satisfy dependencies for other packages and are now no longer needed.
Cleaning the Local Repository Cache
APT caches downloaded package files (.deb files) in /var/cache/apt/archives/. Over time, this cache can grow quite large.
- Execute the following command to remove downloaded package files that can no longer be downloaded:
bash
sudo apt clean
apt cleanclears out the local repository of retrieved package files. It empties the/var/cache/apt/archives/directory.
- To remove only outdated package files, you can use:
bash
sudo apt autoclean
apt autocleanis similar toclean, but it only removes package files that can no longer be downloaded and are largely useless.
Best Practices for System Updates
Adhering to best practices ensures that your Ubuntu Focal system remains secure, stable, and performs optimally after applying updates.
Regular Update Schedule
Establish a routine for checking and applying updates. For personal systems, weekly checks are usually sufficient. For servers, a more frequent schedule might be necessary, especially for security updates.
Backup Before Major Updates
While Ubuntu’s update system is generally reliable, it’s always prudent to back up your important data before performing significant system upgrades or applying a large number of updates. This provides a safety net in case of unexpected issues.
Reviewing Changes
Before confirming any update operation, especially apt dist-upgrade, take a moment to review the list of packages that will be installed, upgraded, or removed. If you are unsure about any specific package, it’s better to research it or postpone the update.
Restarting After Updates
Many updates, particularly those affecting the kernel, system libraries, or core system services, require a system restart to take full effect. Always restart your system when prompted after a significant update to ensure all changes are properly applied.
Managing Third-Party Repositories (PPAs)
While PPAs can provide access to newer software versions not yet available in official Ubuntu repositories, they also introduce potential risks.
- Trustworthiness: Only add PPAs from sources you trust. Unverified PPAs can distribute malicious or unstable software.
- Compatibility: Ensure the PPA is compatible with your Ubuntu version (Focal Fossa, 20.04 LTS). Using a PPA for a different Ubuntu release can lead to dependency conflicts and system instability.
- Disabling PPAs: If you encounter issues after adding a PPA, you can disable it through the “Software & Updates” application or by commenting out its entry in
/etc/apt/sources.list.d/.
Understanding Kernel Updates
Kernel updates are among the most critical system updates. They are responsible for managing your hardware and core system processes.
- New Kernels: When a new kernel is released and installed, your system will typically boot into the newest one by default. Older kernels are kept as a fallback option.
- Removing Old Kernels: Over time, you may accumulate several old kernel versions. You can safely remove these to free up disk space using
sudo apt autoremove. This command is designed to intelligently remove old, unused kernels.

Using apt-get vs. apt
Historically, apt-get was the primary command-line tool for package management. The newer apt command offers a more user-friendly interface, combining functionalities of apt-get and apt-cache with progress indicators and a more intuitive output. For most users on Ubuntu Focal, apt is the recommended command. However, apt-get is still widely used and fully supported. The commands sudo apt-get update, sudo apt-get upgrade, and sudo apt-get dist-upgrade function similarly to their apt counterparts.
By diligently following these guidelines and understanding the mechanisms behind Ubuntu’s update system, you can confidently maintain a secure, up-to-date, and robust Ubuntu Focal Fossa installation.
