link:++https://github.com/rpm-software-management/dnf-plugins-extras++[`dnf-plugin-system-upgrade`] is a plugin for the xref:dnf.adoc[DNF] package manager and is used to upgrade your system to the current release of Fedora.
For Fedora Silverblue and Fedora CoreOS, which use rpm-ostree, you may refer to link:++https://coreos.github.io/rpm-ostree/administrator-handbook/++[rpm-ostree documentation] for details.
*Back up your data* before performing a system-wide upgrade as every system upgrade is potentially risky.
As a precaution, download the link:++https://getfedora.org/en/workstation/download/++[Fedora Workstation Live image] in the event something goes wrong.
*Important:* Do not skip this step. System updates are required to receive signing keys of higher-versioned releases, and they often fix problems related to the upgrade process.
Most people will want to upgrade to the latest stable release, which is `{MAJOROSVER}`, but in some cases, such as when you're currently running an older release than `{PREVVER}`, you may want to upgrade just to Fedora `{PREVVER}`. System upgrade is only officially supported and tested over 2 releases at most (e.g. from `{PREVPREVVER}` to `{MAJOROSVER}`). If you need to upgrade over more releases, it is recommended to do it in several smaller steps (<<sect-how-many-releases-can-i-upgrade-across-at-once,read more>>).
You can also use `{NEXTVER}` to upgrade to a link:https://fedoraproject.org/wiki/Releases/Branched[Branched] release, or `rawhide` to upgrade to link:https://fedoraproject.org/wiki/Releases/Rawhide[Rawhide]. Note that neither of these two are stable releases. For details about the upgrade process and common issues related to those two releases, please look at appropriate sections on aforelinked pages.
. If some of your packages have unsatisfied dependencies, the upgrade will refuse to continue until you run it again with an extra `--allowerasing` option.
* In case of unsatisfied dependencies, you can sometimes see more details if you add `--best` option to the command line.
* If you want to remove/install some packages manually before running `dnf system-upgrade download` again, it is advisable to perform those operations with `--setopt=keepcache=1` dnf command line option.
. Trigger the upgrade process. This will reboot your machine (immediately!, without a countdown or confirmation, so close other programs and save your work) into the upgrade process running in a console terminal:
Most configuration files are stored in the `/etc` folder.
If you have changed the package's configuration files, RPM creates new files with either `.rpmnew` (the new default config file), or `.rpmsave` (your old config file backed up).
You can search for these files, or use the `rpmconf` tool that simplifies this process. To install rpmconf, enter:
Some third party software drop edited configuration files in `/etc/yum.repos.d/` and reverting these files to their original versions may disable updates for the software.
Please remember to review configuration files in this directory carefully.
If you use `rpmconf` to upgrade the system configuration files supplied with the upgraded packages then some configuration files may change. After the upgrade you should verify `/etc/ssh/sshd_config`, `/etc/nsswitch.conf`, `/etc/ntp.conf` and others are expected. For example, if OpenSSH is upgraded then `sshd_config` reverts to the default package configuration. The default package configuration *does not* enable public key authentication, and allows password authentication.
After you boot into the latest kernel and test the system you can remove previous kernels. Old kernels remain even after `dnf autoremove` to avoid unintentional removals.
One of the easier ways to remove old kernels is with a script that retains the latest kernel. The script below works whenever Fedora updates a kernel, and does not depend upon a system upgrade.
There may be some dangling symlinks in the filesystem after an upgrade. You can clean the dangling links by installing the symlinks utility and deleteing the old links.
The system upgrade tool uses `dnf distro-sync` by default.
If your system is partly upgraded or you see some package dependency issues, try running another distro-sync manually to see if this fixes the problem.
This will attempt to make your installed packages the same version in your currently enabled repositories, even if it must downgrade some packages:
. See link:++https://fedoraproject.org/wiki/Bugs/Common++[Common bugs] to check if it is a known problem the community is already aware of.
. Search link:++https://bugzilla.redhat.com/buglist.cgi?product=Fedora&component=dnf-plugin-system-upgrade&resolution=---++[Bugzilla for an existing bug report].
If you do not see a report that matches your symptoms, you can file a new report from the search page.
Please follow the bug reporting instructions mentioned in the link:++https://github.com/rpm-software-management/dnf-plugin-system-upgrade/blob/master/README.md++[README from the github repo] or in `man dnf.plugin.system-upgrade`.
If you encounter any issues after the upgrade with a specific package, file a bug against the package with which you are having issues.
The package signing keys for the newer Fedora release are sent to older Fedora releases to allow DNF to verify the integrity of the downloaded packages.
You can disable this function if needed, but is not recommended as you will be open to attacks from malicious software.
Yes, if they are configured like regular DNF repositories and the version numbers are not hard-coded in the repository file (usually found in `/etc/yum.repos.d/`.)
Commonly used third-party repositories like RPM Fusion should work.
However, if attempting to upgrade prior to, or soon after, an official Fedora release, they may not have updated their repository paths, and DNF may be unable to find their packages.
Usually, this should not prevent the upgrade from running successfully.
Also, you can update packages from the third-party repository later.
It is strongly recommended to upgrade an EOL release on any production system, or any system connected to the public internet.
Any upgrade from Fedora 20 or earlier is done *at your own risk* as DNF was not the default package management tool.
However, if you do have a release newer than Fedora 20 that is EOL, you can attempt to do an upgrade, but this method is *not supported*.
You may try to upgrade through intermediate releases until you reach a currently-supported release, or try to upgrade to a currently-supported release in a single operation.
Upgrades to the very next release (e.g. `{PREVVER}` to `{MAJOROSVER}`) as well as upgrades skipping one release (e.g. `{PREVPREVVER}` to `{MAJOROSVER}`) are both supported. However, it is highly recommended to perform the upgrade before your release gets End of Life (EOL). That happens roughly a month after N+2 release has been released (when you're currently on release N). The link:https://fedoraproject.org/wiki/Fedora_Release_Life_Cycle[Fedora Release Life Cycle] is specifically designed to provide this approximate one month "grace period" to allow users the choice to upgrade their systems on a yearly basis, i.e. once every two releases. You can study link:https://fedoraproject.org/wiki/Releases[Releases] to see the current release status and schedule. Around a month after the new release comes out, the last-but-one release becomes End of Life (EOL). The upgrade is likely to work successfully after the release goes EOL, but the time period after the new release may be uncertain.
