Downgrading packages
Before downgrading a single or multiple packages, consider why you wish to do so. If it is due to a bug, search the bug tracker for existing tasks. If there is none, add a new task; it is better to correct bugs, or at least warn other users of possible issues.
- Downgrading one package may require that its dependencies be downgraded as well. When the number of packages to downgrade is large, consider using a snapshot. See Arch Linux Archive#How to restore all packages to a specific date.
- Be careful with changes to configuration files and scripts. For now pacman will handle this for us, as long as we do not bypass its safeguards.
- If a downgrade involves a soname change, all dependencies may need downgrading or rebuilding too.
Return to an earlier package version
Using the pacman cache
If a package was installed at an earlier stage, and the pacman cache was not cleaned, install an earlier version from /var/cache/pacman/pkg/.
This process will remove the current package and install the older version. Dependency changes will be handled, but pacman will not handle version conflicts. If a library or other package needs to be downgraded with the packages, please be aware that you will have to downgrade this package yourself as well.
# pacman -U /var/cache/pacman/pkg/package-old_version.pkg.tar.type
Note that type will be xz for older package builds, and zst for those following the 2020 change.
Once the package is reverted, temporarily add it to the IgnorePkg section of pacman.conf, until the difficulty with the updated package is resolved.
Downgrading the kernel
In case of issue with a new kernel, the Linux packages can be downgraded to the last working ones #Using the pacman cache. Go into the directory /var/cache/pacman/pkg and downgrade at least linux, linux-headers and any kernel modules. For example:
# pacman -U linux-4.15.8-1-x86_64.pkg.tar.xz linux-headers-4.15.8-1-x86_64.pkg.tar.xz virtualbox-host-modules-arch-5.2.8-4-x86_64.pkg.tar.xz
/mnt. If you have /boot or /var on separate partitions, also mount them to /mnt (e.g. mount /dev/sdc3 /mnt/boot). Then chroot into the system using: # arch-chroot /mnt /bin/bashNow you can go into the pacman cache directory and downgrade the Linux packages using the command indicated above. Once done, exit the chroot (with
exit) and reboot.Arch Linux Archive
The Arch Linux Archive is a daily snapshot of the official repositories. It can be used to install a previous package version, or restore the system to an earlier date.
Rebuild the package
If the package is unavailable, find the correct PKGBUILD and rebuild it with makepkg.
For packages from the official repositories, retrieve the PKGBUILD with ABS and change the software version. Alternatively, find the package on the Packages website, click "View Changes", and navigate to the desired version. The necessary files can then be downloaded from the directory so that the package can be rebuilt.
See also Arch Build System#Checkout an older version of a package.
Old AUR packages can be built by checking out an old commit in the AUR package Git repository. For pre-2015 AUR3 PKGBUILDs, see Arch User Repository#Git repositories for AUR3 packages.
Automation
downgrader-gitAUR is a tool which works with libalpm, supports the pacman log and downgrading packages using Arch Linux Archive, local cache and ARM.
The downgradeAUR package is a Bash script to downgrade one (or multiple) packages, by using the pacman cache or the Arch Rollback Machine. See man downgrade for details.