Troubleshooting common issues while upgrading from RHEL 7 to RHEL 8

Environment

• Red Hat Enterprise Linux Server 7
• leapp

Issue

• How do I perform an in-place upgrade from Red Hat Enterprise Linux 7 to Red Hat Enterprise Linux 8?

Resolution

The RHEL 8 Documentation details all necessary steps for the upgrade process. It is recommended to carefully review the section regarding limitations and requirements as the process is only supported under specific circumstances.

• Upgrading to RHEL 8
• Considerations in Adopting RHEL 8
• In-place upgrade Support Policy
• Supported in-place upgrade paths for Red Hat Enterprise Linux
• Customizing your Red Hat Enterprise Linux in-place upgrade

A collection of knowledge base articles describing known issues is listed below.
Please carefully read the articles (in particular the Diagnostic Steps sections) prior to upgrading just in case some may apply to your system, this will prevent a failure to happen and recovery to be difficult or impossible:

• Pre Upgrade step

  • Why does leapp preupgrade fail with sqlite3.OperationalError: unable to open database file traceback error ?
  • leapp fails with "There is not enough space on the file system hosting /var/lib/leapp directory to extract the packages"
  • [leapp] At least X MB more space needed on the </XXX> filesystem
  • Leapp fails on VMWare guest with an error "Inhibitor: Detected loaded kernel drivers which have been removed in RHEL 8. Upgrade cannot proceed." for drivers mptbase, mptscsih and mptspi
  • Leapp preupgrade getting "Inhibitor: Detected loaded kernel drivers which have been removed in RHEL 8. Upgrade cannot proceed."
  • RHEL7: "leapp preupgrade" fails with message "Unable to use yum successfully"
  • RHEL 7 to RHEL 8 LEAPP Upgrade Failing When Using Red Hat Satellite
  • Leapp In-Place Upgrade: how to check DNF is working with the Satellite repositories from the client side?
  • RHEL7: "leapp preupgrade" fails with message "Failed to synchronize cache for repo"
  • leapp upgrade fails with The value of "rhui" field must be one of ", aws, azure"
  • Leapp can fail with OverlayFS + XFS ftype=1
  • Leapp preupgrade fails with: The pam_tally2 pam module(s) no longer available
  • leapp upgrade stops with Inhibitor "Upgrade requires links in root directory to be relative"
  • Leapp fails with "Could not check for valid GPG keys"
  • Detected a corrupted grubenv file
  • Why does leapp upgrade fail with error "Command ['chroot', '/var/lib/leapp/el8userspace', '/bin/bash', '-c', 'su - -c update-ca-trust'] failed with exit code 127" ?
  • Why does leapp upgrade fail with error "Command ['chroot', '/var/lib/leapp/el8userspace', '/bin/bash', '-c', 'su - -c update-ca-trust'] failed with exit code 1" ?

• Upgrade step

  • Leapp upgrade fails with "DNF execution failed with non zero exit code."
  • Leapp upgrade fails with "Cannot obtain data about the DNF configuration" while in reboot phase

• Reboot step

  Whenever an error occurs during the Reboot step, collect the rdsosreport before opening a case, refer to Leapp upgrade fails and drops to emergency mode for the procedure.

  • RHEL7: "leapp upgrade" fails in reboot phase with message "OSError: [Errno 17] File exists: '/root/tmp_leapp_py3'" then enters emergency
  • RHEL7: "leapp upgrade" fails in reboot phase with message "OSError: [Errno 30] Read-only file system" then enters Emergency mode
  • RHEL7: "leapp upgrade" fails in reboot phase with message "BLS file /boot/loader/entries/XXX.conf already exists" then system reboots automatically
  • RHEL7: "leapp upgrade" fails in reboot phase with no message and enters emergency prompt
  • Leapp fails to upgrade the system in reboot phase and prints "Message: Failed to append extra arguments to kernel command line."
  • s390x/ZFCP: leapp fails in reboot phase when executing "zipl-switch-to-blscfg" command
  • Why does leapp upgrade fails in emergency with error "UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 1: ordinal not in range(128)"?
  • Leapp fails with 'Grubby listed args= multiple times with different values' or 'Grubby output is malformed'.
  • RHEL7: leapp upgrade crashes during reboot phase with "Failed to retrieve kernel command line to save for future installed kernels"
  • RHEL7: "leapp upgrade" fails in reboot phase with message "/usr/bin/bash: /usr/bin/python3: No such file or directory" then enters emergency mode"
  • leapp fails in reboot phase with "Cannot obtain data about the DNF configuration" error message

• Post Upgrade step

  • leapp post-upgrade task "yum remove kernel-workaround [...]" fails with "Problem: The operation would result in removing the following protected packages: dnf"
  • Leapp: "netconsole" SysV initscripts symbolic links are not removed after upgrade
  • Updating the kernel of systems upgraded by Leapp doesn't generate the initramfs
  • RHEL8/zVM: some disk or network devices are missing after upgrading using Leapp from RHEL7
  • The Dell system does not use the biosdevname scheme by default in RHEL 8

• Miscellaneous

  • The best practices and recommendations for performing RHEL Upgrade using Leapp
  • Consolidated Troubleshooting Article for Red Hat Satellite 6.x LEAPP Issues
  • This content is not included.How to in-place upgrade SAP environments from RHEL 7 to RHEL 8
  • How to in-place upgrade an offline / disconnected RHEL 7 machine to RHEL 8 with Leapp?
  • RHEL7/VMWare - How to change SCSI controller from LSI Logic SAS or Parallel to VMware Paravirtual
  • leapp: How to solve Risk Factor HIGH "GRUB core will be updated during upgrade"
  • How to perform an in-place upgrade to RHEL 8 when using kernel NIC names on RHEL 7
  • RHEL7: how to strace the reboot phase of leapp
  • Installing leapp-upgrade on RHEL 7.9 fails with 'Error: Package: audit-libs-python-2.8.5-4.el7.x86_64 (rhel-7-server-rpms)

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