Update or manage software on your system and on your schedule using Discover or command-line. Continue to work while updates are being installed.
Please read the disclaimer before proceeding. This solution is updated regularly. If you have suggestions or requests, please share your thoughts on the Guided Solution Authorship Form.
Ubuntu, Kubuntu, and most derivatives use Debian packages and the Apt system to install and update most software. The official documentation provides a great overview of all the pieces.
We recommend you Upgrade your system once per day. This keeps your system up-to-date with the latest security and feature enhancements. Updates on the Focus rarely cause issues because it ships with only 20.04 Long Term Support (LTS) releases which are designed to minimize breakage. The Focus team also run daily regression tests to identify and quickly fix issues.
Even with all these safeguards, however, we still recommend delaying updates until after critical work is done for the day. Although glitches are rare, it is best to deal with them on your own terms. If you do need to revert a change, you may use the apt-rollback tool we have included. As with any package management tool, use this carefully and always backup your data.
The Discover package manager is the official KDE GUI to update, browse, install, and remove most software from the system. It is built on top of the apt package system. Please refer to the documentation as needed.
The typical update procedure is illustrated below. Package updates are indicated by a blue dot in the system tray.
Click on the update indicator to review changes.
After Update is clicked, Discover starts and the update list is refreshed.
Click on the Update All button to start the process.
User authorization is required.
The update takes seconds or minutes depending on the number of packages.
After updates are complete Discover will appear as shown.
Discover can find, install or remove software.
One can manage software using the apt package tools including apt, apt-get, apt-cache, aptitude, and wajig. We recommend using apt for daily maintenance, and aptitude when resolving more complex package issues.
The CLI tools use update as the keyword to update the list of software, while the upgrade keyword is used to install newer packages.
Q: I appear to have a number of unused packages. How can I remove them?
A: Enter the following into a terminal: sudo apt autoremove
Q: You used to also show Muon as an option. What happened?
A: As of Fall 2020 Muon does not appear actively developed. In addition, Discover has gotten significantly faster and more powerful. As a result, we dropped Muon from this guide on 2020-09-28.
Q: Discover proxy settings gets stuck. How can I resolve this?
A: Enter the following commands and follow steps.
Q: I see the following error message when fetching software updates. This happens when using Discover or the command-line. How can I fix this?
A: This is due to expired key. This can be fixed as illustrated below.
The keyserver URL may alternately be hkp://keyserver.ubuntu.com:80. This This can be useful when working through firewalls. After updating the key, the error should be eliminated.
Q. I am seeing similar key issues with the QGIS repositories. Can I fix this too?
A: Yes. Try sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys F7E06F06199EF2F2 (thanks Justin!).
This is a partial revision history. See the git repository for all entries.
2021-03-21 2a8443b2 Clarified language2020-09-28 fb8295ec Removed Muon as deprecated2020-09-10 5f5c2fe5 Added expired key actions in troubleshooting2020-06-10 c4ed9299 Restructure layoutWe try hard to provide a useful solution validated by professionals. However, we cannot anticipate every situation, and therefore cannot guarantee this procedure will work for your needs. Always backup your data and test the solution to determine the correct procedure for you.
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