Chapter 6. Performing the upgrade from RHEL 7 to RHEL 8
Upgrade to RHEL 8 using the Leapp
utility.
Prerequisites
- The steps listed in Preparing for the upgrade have been completed, including a full system backup.
- The steps listed in Reviewing the pre-upgrade report have been completed and all reported issues resolved.
Procedure
On your RHEL 7 system, start the upgrade process:
# leapp upgrade --target <target_os_version>
Replace <target_os_version> with the target operating system (OS) version, for example 8.10. If no target OS version is defined,
Leapp
uses the default target OS version specified in the table 1.1 in Supported upgrade paths.NoteIf you are using custom repositories from the
/etc/yum.repos.d/
directory for the upgrade, enable the selected repositories as follows:# leapp upgrade --enablerepo <repository_id1> --enablerepo <repository_id2> …
If you are upgrading without RHSM or using RHUI, add the
--no-rhsm
option.If you are upgrading by using an ISO image, add the
--no-rhsm
and--iso <file_path>
options. Replace <file_path> with the file path to the saved ISO image, for example/home/rhel8.iso
.If you have an Extended Upgrade Support (EUS), Advanced Update Support (AUS), or Update Services for SAP Solutions (E4S) subscription, add the
--channel <channel>
option:-
If you are upgrading to RHEL 8.8, replace channel with the value you used with the
leapp preupgrade
command, for example,eus
,aus
, ore4s
. Note that you must use the same value with the--channel
option in both theleapp preupgrade
andleapp upgrade
commands. -
If you are upgrading to RHEL 8.10, replace channel with
ga
.
At the beginning of the upgrade process,
Leapp
performs the pre-upgrade phase described in Reviewing the pre-upgrade report.If the system is upgradable,
Leapp
downloads necessary data and prepares an RPM transaction for the upgrade.If your system does not meet the parameters for a reliable upgrade,
Leapp
terminates the upgrade process and provides a record describing the issue and a recommended solution in the/var/log/leapp/leapp-report.txt
file. For more information, see Troubleshooting.-
If you are upgrading to RHEL 8.8, replace channel with the value you used with the
Manually restart the system:
# reboot
In this phase, the system boots into a RHEL 8-based initial RAM disk image, initramfs.
Leapp
upgrades all packages and automatically reboots to the RHEL 8 system.Alternatively, you can enter the
leapp upgrade
command with the--reboot
option and skip this manual step.If a failure occurs, investigate logs as described in Troubleshooting.
- Log in to the RHEL 8 system and verify its state as described in Verifying the post-upgrade state of the RHEL 8 system.
- Perform all post-upgrade tasks described in the upgrade report and in Performing post-upgrade tasks. Especially, re-evaluate and re-apply your security policies.
- In case of upgrading a system that was and will be running in FIPS mode, remove any RHEL 7 kernels. Then, regenerate and otherwise ensure the FIPS compliance of all cryptographic keys. See Locations of cryptographic keys in RHEL 8 for more information.