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 the snactor package. During the in-place upgrade, Leapp packages that were installed with the Leapp 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 these Leapp 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 desired Leapp packages from the exclude list. To remove all packages from the exclude list: Remove remaining RHEL 7 packages, including remaining Leapp packages. Determine old kernel versions: Remove weak modules from the old kernel. If you have multiple old kernels, repeat the following step for each kernel: Replace <version> with the kernel version determined in the step, for example: Note Ignore the following error message, which is generated if the kernel package has been previously removed: Remove the old kernel from the boot loader entry. If you have multiple old kernels, repeat this step for each kernel: Replace version with the kernel version determined in the step, for example: Locate remaining RHEL 7 packages: 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, use YUM or DNF when performing these actions. Review the transaction before accepting to ensure no packages are unintentionally removed. For example: Remove remaining Leapp dependency packages: Remove any remaining empty directories: Optional: Remove all remaining upgrade-related data from the system: Important Removing 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: 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: Reinstall the rescue kernel and related initial RAM disk: Note If 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: Optional: Review, remediate, and then remove the rpmnew , rpmsave , and leappsave files. Note that rpmsave and leappsave 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: Verify that the previously removed rescue kernel and rescue initial RAM disk files have been created for the current kernel: Verify the rescue boot entry refers to the existing rescue files. See the grubby output:

Commands:
yum config-manager --save --setopt exclude=''
cd /lib/modules && ls -d *.el7*
[ -x /usr/sbin/weak-modules ] && /usr/sbin/weak-modules --remove-kernel <version>
[ -x /usr/sbin/weak-modules ] && /usr/sbin/weak-modules --remove-kernel 3.10.0-1160.25.1.el7.x86_64
/usr/sbin/weak-modules: line 1081: cd: /lib/modules/ <version> /weak-updates: No such file or directory
/bin/kernel-install remove <version> /lib/modules/ <version> /vmlinuz
/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
rpm -qa | grep -e '\.el[67]' | grep -vE '^(gpg-pubkey|libmodulemd|katello-ca-consumer)' | sort
yum remove kernel-workaround USD(rpm -qa | grep \.el7 | grep -vE 'gpg-pubkey|libmodulemd|katello-ca-consumer')
yum remove leapp-deps-el8 leapp-repository-deps-el8
rm -r /lib/modules/*el7*
rm -rf /var/log/leapp /root/tmp_leapp_py3 /var/lib/leapp
yum config-manager --set-disabled <repository_id>
rm /boot/vmlinuz-*rescue* /boot/initramfs-*rescue*
/usr/lib/kernel/install.d/51-dracut-rescue.install add "USD(uname -r)" /boot "/boot/vmlinuz-USD(uname -r)"
zipl
grubby --info=ALL | grep "\.el7" || echo "Old kernels are not present in the boot loader."
ls /boot/vmlinuz-*rescue* /boot/initramfs-*rescue* lsinitrd /boot/initramfs-*rescue*.img | grep -qm1 "USD(uname -r)/kernel/" && echo "OK" || echo "FAIL"
grubby --info USD(ls /boot/vmlinuz-*rescue*)