Chapter 8. Performing post-upgrade tasks
The following major tasks are recommended after an in-place upgrade to RHEL 8.
Prerequisites
- You have upgraded the system following the steps described in Performing the upgrade from RHEL 7 to RHEL 8 and you have been able to log in to RHEL 8.
- You have verified the status of the in-place upgrade following the steps described in Verifying the post-upgrade status of the RHEL 8 system.
Procedure
After performing the upgrade, complete the following tasks:
Remove any remaining
Leapp
packages from the exclude list in the/etc/dnf/dnf.conf
configuration file, including thesnactor
package. During the in-place upgrade,Leapp
packages that were installed with theLeapp
utility are automatically added to the exclude list to prevent critical files from being removed or updated. After the in-place upgrade, you must remove theseLeapp
packages from the exclude list before they can be removed from the system.-
To manually remove packages from the exclude list, edit the
/etc/dnf/dnf.conf
configuration file and remove the desiredLeapp
packages from theexclude
list. To remove all packages from the
exclude
list:# yum config-manager --save --setopt exclude=''
-
To manually remove packages from the exclude list, edit the
Remove remaining RHEL 7 packages, including remaining
Leapp
packages.Determine old kernel versions:
# cd /lib/modules && ls -d *.el7*
Remove weak modules from the old kernel. If you have multiple old kernels, repeat the following step for each kernel:
# [ -x /usr/sbin/weak-modules ] && /usr/sbin/weak-modules --remove-kernel <version>
Replace <version> with the kernel version determined in the previous step, for example:
# [ -x /usr/sbin/weak-modules ] && /usr/sbin/weak-modules --remove-kernel 3.10.0-1160.25.1.el7.x86_64
NoteIgnore the following error message, which is generated if the kernel package has been previously removed:
/usr/sbin/weak-modules: line 1081: cd: /lib/modules/<version>/weak-updates: No such file or directory
Remove the old kernel from the boot loader entry. If you have multiple old kernels, repeat this step for each kernel:
# /bin/kernel-install remove <version> /lib/modules/<version>/vmlinuz
Replace version with the kernel version determined in the previous step, for example:
# /bin/kernel-install remove 3.10.0-1160.25.1.el7.x86_64 /lib/modules/3.10.0-1160.25.1.el7.x86_64/vmlinuz
Locate remaining RHEL 7 packages:
# rpm -qa | grep -e '\.el[67]' | grep -vE '^(gpg-pubkey|libmodulemd|katello-ca-consumer)' | sort
Remove remaining RHEL 7 packages, including old kernel packages, and the
kernel-workaround
package from your RHEL 8 system. To ensure that RPM dependencies are maintained, useYUM
orDNF
when performing these actions. Review the transaction before accepting to ensure no packages are unintentionally removed.For example:
# yum remove kernel-workaround $(rpm -qa | grep \.el7 | grep -vE 'gpg-pubkey|libmodulemd|katello-ca-consumer')
Remove remaining
Leapp
dependency packages:# yum remove leapp-deps-el8 leapp-repository-deps-el8
Remove any remaining empty directories:
# rm -r /lib/modules/*el7*
Optional: Remove all remaining upgrade-related data from the system:
# rm -rf /var/log/leapp /root/tmp_leapp_py3 /var/lib/leapp
ImportantRemoving this data might limit Red Hat Support’s ability to investigate and troubleshoot post-upgrade problems.
Disable YUM repositories whose packages cannot be installed or used on RHEL 8. Repositories managed by RHSM are handled automatically. To disable these repositories:
# yum config-manager --set-disabled <repository_id>
Replace <repository_id> with the repository ID.
Replace the old rescue kernel and initial RAM disk with the current kernel and disk:
Remove the existing rescue kernel and initial RAM disk:
# rm /boot/vmlinuz-*rescue* /boot/initramfs-*rescue*
Reinstall the rescue kernel and related initial RAM disk:
# /usr/lib/kernel/install.d/51-dracut-rescue.install add "$(uname -r)" /boot "/boot/vmlinuz-$(uname -r)"
NoteIf your system’s kernel package has a different name, such as on real-time systems, replace
kernel-core
with the correct package name.If your system is on the IBM Z architecture, update the
zipl
boot loader:# zipl
-
Optional: Review, remediate, and then remove the
rpmnew
,rpmsave
, andleappsave
files. Note thatrpmsave
andleappsave
are equivalent and can be handled similarly. For more information, see What are rpmnew & rpmsave files? - Re-evaluate and re-apply your security policies. Especially, change the SELinux mode to enforcing. For details, see Applying security policies.
Verification
Verify that the old kernels have been removed from the boot loader entry:
# grubby --info=ALL | grep "\.el7" || echo "Old kernels are not present in the boot loader."
Verify that the previously removed rescue kernel and rescue initial RAM disk files have been created for the current kernel:
# ls /boot/vmlinuz-*rescue* /boot/initramfs-*rescue* # lsinitrd /boot/initramfs-*rescue*.img | grep -qm1 "$(uname -r)/kernel/" && echo "OK" || echo "FAIL"
Verify the rescue boot entry refers to the existing rescue files. See the grubby output:
# grubby --info $(ls /boot/vmlinuz-*rescue*)