Upgrading to Fedora 42: Smooth Sailing… Until It Wasn't

Upgrading to Fedora 42: Smooth Sailing… Until It Wasn't

Last week, I bit the bullet and upgraded both my personal desktop and work laptop (Lenovo P1) to Fedora 42. With Fedora 41 retiring in less than 6 months, procrastination wasn’t an option. Here’s my experience - including the moment my desktop decided to play dead during the upgrade.

The recommended way to upgrade to the latest Fedora release, is to use the Discover app. I chose the command line, as Discover has caused past issues with upgrades becoming “stuck” and providing no visibility into what was going on. If you choose to do the same, do not skip any of the steps.

Failure to Prepare is Preparing to Fail

Maybe your last Fedora major upgrade when smoothly. That doesn’t mean that this one will. Take precautions:

  • Perform, and test, a backup: Use your preferred tool to back up your system. That could be as simple as a file copy to an external drive. Sure it will take a while and be frustrating. Do you know what is more frustrating? Losing your data.
  • Download, and test, a live image: If you encounter any upgrade issues, a bootable live image is a life-saver. Download one and test that you can boot from it.

Failing to Prepare When You’ve Been Reminded to Prepare is Stupid

Sods Law exists for times like these. Don’t progress until you’ve backed up your system, tested it, downloaded a live image and ensure you can boot from it.

Let’s Begin The Upgrade

Step 1: Ensure Fedora Is Fully Up-to-Date

If you have upgraded Fedora from the command line before, this command will be familiar.

$ sudo dnf upgrade --refresh

If you haven’t used the --refresh switch before, it simply tells dnf to get the latest metadata now.

Normally you’d be unlikely to need to reboot but before a system upgrade, let’s just do it to make sure. After the reboot, do this step again, and again until there are no more upgrades available. Then move onto …

Step 2: Determine the Upgrade Version

Fedora only guarantees an upgrade of 2 major versions. So if you’re on 40, or later, you’re good to go to 42. If you’re running 39 and earlier, you’re best to jump up only 2 major releases at a time (so from 39, go to 41 and then 42). See step 2 of the Fedora documentation:

Most people will want to upgrade to the latest stable release, which is 42, but in some cases, such as when you’re currently running an older release than 41, you may want to upgrade just to Fedora Linux 41. System upgrade is only officially supported and tested over 2 releases at most (e.g. from 40 to 42). If you need to upgrade over more releases, it is recommended to do it in several smaller steps (read more).

Step 3: Upgrade the System

To start the upgrade process, run the following command replacing UPGRADE VERSION with the version number you are going to upgrade to:

$ sudo dnf system-upgrade download --releasever=<UPGRADE VERSION>

So if you are going to upgrade to Fedora 42, run:

$ sudo dnf system-upgrade download --releasever=42

For Fedora 42, you’ll see output similar to what is below:

Upgrading groups:
 Virtualization
 LibreOffice
 KDE Spin Initial Setup
 KDE PIM
 KDE Multimedia support
 KDE Applications
 Firefox Web Browser
 Development Tools
 Anaconda tools
Upgrading groups:
 Standard
 Printing Support
 Common NetworkManager Submodules
 Multimedia
 KDE
 Input Methods
 Hardware Support
 Guest Desktop Agents
 Fonts
 Dial-up Networking Support
 Desktop accessibility
 Core
 base-graphical
Upgrading environmental groups:
 KDE Plasma Workspaces

Transaction Summary:
 Installing:        65 packages
 Upgrading:       2871 packages
 Replacing:       2879 packages
 Removing:           6 packages
 Downgrading:        1 package

Total size of inbound packages is 3 GiB. Need to download 3 GiB.
After this operation, 123 MiB extra will be used (install 11 GiB, remove 11 GiB).
Is this ok [y/N]:

Once you see this output, press `Y` to continue the install

Press y to continue the upgrade. Eventually, you’ll then be prompted to accept the new Fedora 42 GPG key:

Importing OpenPGP key 0x105EF944:
 UserID     : "Fedora (42) <[email protected]>"
 Fingerprint: B0F4950458F69E1150C6C5EDC8AC4916105EF944
 From       : file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora-42-x86_64
Is this ok [y/N]:

You know what to do (press y again):

The key was successfully imported.
Transaction stored to be performed offline. Run `dnf5 offline reboot` to reboot and run the transaction. To cancel the transaction and delete the downloaded files, use `dnf5 offline clean`.
Complete

And that’s it! Depending on how fast your internet connection and computer are, this can take a few minutes to a few hours. Just be patient and make sure things are still progressing.

Step 4: Reboot

You’ve taken a backup. You’ve tested your backup. You have a bootable live image on-hand, that you’ve tested. It’s time to reboot. Run this command to reboot:

$ sudo dnf system-upgrade reboot

And press y when you see this:

The system will now reboot to upgrade to release version 42.
Is this ok [y/N]

Step 5: Post-Install Tasks

The official Fedora documentation has a section devoted to optional post-install tasks that you may want, or need, to do. I don’t cover those here as I didn’t perform any of them.

My Desktop Upgrade: When Things Don’t Go As Planned

I started to upgrade my personal desktop first with the package upgrade going smoothly. The familiar Fedora logo appeared at the shutdown stage, and it was still there after 5 minutes. Reluctant to interfere with the upgrade process I left it another 10 minutes, watching the hard drive activity light for the last few minutes showed that nothing was happening.

Taking a deep breath, I powered off the desktop. The silence was deafening - no fan noise, no hard drive activity. Just me and a potentially broken system. I pressed the power button again, half expecting to see the dreaded black screen of a failed upgrade.

But then - the familiar Fedora logo appeared… and a few seconds later messages confirming the system upgrade was in progress. What happened is unknown, but the power cycle unstuck the shutdown process. The feeling was not one of victory, but of luck. Everything I had read about the Fedora upgrade process gave me confidence that it was robust and for every upgrade failure, there are 10 or more that upgrade without issue. But somebody has to have a failed upgrade.

In contrast to the desktop computer, the work laptop upgraded without incident.

Much Ado About Upgrades

If you’re concerned about upgrading your system to a major release:

  1. Take precautions. Backup your system and ensure you have a bootable live image you have tested.
  2. Read the official Fedora upgrade documentation and follow:
  3. Upgrade your system until there are no more upgrades left.
  4. Give it time. Don’t rush performing the upgrade. Don’t try to hurry the upgrade process. It will take as long as it takes. Give it time. Hard reset is a last resort.
  5. You took precautions, didn’t you?

The Fedora upgrade process was fairly boring. Not much drama. It just worked. Take your time. Prepare and you’ll be fine.

Final Thoughts

After upgrading both machines to Fedora 42, I’m reminded why I stick with Fedora despite the yearly upgrade dance. The process, while nerve-wracking when things go sideways, is generally robust and well-documented.

My desktop’s hiccup during shutdown was a reminder that backups aren’t optional - they’re insurance against Sods Law. The laptop’s smooth upgrade showed that most of the time, things just work.

Would I do anything differently next time? Probably schedule the upgrades when I have more time to troubleshoot. But overall, Fedora 42 is running beautifully on both machines, and the upgrade process - drama and all - took less than an hour total.

What’s your Fedora upgrade story? Have you had any heart-stopping moments during a system upgrade? I’d love to hear about your experiences!

And if you’re still on Fedora 41, don’t wait too long - that retirement date is coming up fast!