The libguestfs-benchmarking and lld-test packages are not included in Oracle Linux 8.6. Consequently, if your Oracle Linux 8.5 system includes these packages, upgrading the system to Oracle Linux 8.6 fails.

To work around this issue, remove these packages from the system prior to upgrading to Oracle Linux 8.6. For example:

sudo dnf remove libguestfs-benchmarking lld-test

(Bug ID 34122488)

During an upgrade from Oracle Linux 8.5 to Oracle Linux 8.6, and with the appropriate Oracle Linux 8 repositories enabled, the dnf upgrade command displays messages similar to the following:

Running scriptlet: systemd-239-44.0.1.el8.x86_64                    
4550/4550
[/usr/lib/tmpfiles.d/dnssec-trigger.conf:1] Line references path below legacy
directory /var/run/, updating /var/run/dnssec-trigger → /run/dnssec-trigger;
please update the tmpfiles.d/ drop-in file accordingly.
[/usr/lib/tmpfiles.d/krb5-krb5kdc.conf:1] Line references path below legacy
directory /var/run/, updating /var/run/krb5kdc → /run/krb5kdc; please update
the tmpfiles.d/ drop-in file accordingly.
[/usr/lib/tmpfiles.d/nss-pam-ldapd.conf:2] Line references path below legacy
directory /var/run/, updating /var/run/nslcd → /run/nslcd; please update the
tmpfiles.d/ drop-in file accordingly.
[/usr/lib/tmpfiles.d/pesign.conf:1] Line references path below legacy
directory /var/run/, updating /var/run/pesign → /run/pesign; please update
the tmpfiles.d/ drop-in file accordingly.
[/usr/lib/tmpfiles.d/portreserve.conf:1] Line references path below legacy
directory /var/run/, updating /var/run/portreserve → /run/portreserve; please
update the tmpfiles.d/ drop-in file accordingly.
.
.
.

These messages can be safely ignored, as the upgrade or package installation completes successfully.

As an alternative workaround, update the configuration by following the instructions in the message. Change the legacy var/run/<...> directory path to /run/<...>.

(Bug ID 32852433)

During a Preboot Execution Environment (PXE) installation of Oracle Linux 8, the installer automatically enables the Ethernet over USB network interface with the bootproto=dhcp and ONBOOT=yes parameters. These default settings causes the NetworkManager service to fail to start.

To prevent this issue from occurring, or to resolve the issue if you have already encountered it, use one of the following workarounds:

• Prior to installation, disable the ONBOOT parameter for the Ethernet over USB network interface in the kickstart file, as follows:

  network --bootproto=dhcp --device=enp0s20f0u8u3c2 --onboot=off --ipv6=auto

• During installation, on the Network & Host Name screen, do not select the Connect automatically with priority check box to connect automatically on every reboot for the Ethernet over USB network interface.

• If you have already encountered this issue, then after the installation, change the network configuration setting for the Ethernet over USB network interface to ONBOOT=no. Then reboot the system.

(Bug ID 31888490)

If you selected an alternate language while using the text-based installer to install the OS, you cannot proceed with the installation. The installation is blocked with [!] flags for Software Selection and Installation Destination regardless of what you have set for these two options.

However, this issue does not occur if you are performing an installation by using the default English language selection or by using the graphical installation program.

(Bug IDs 30535416, 29648703)

A minor upstream usability error affects the graphical installation program during the configuration of Kdump.

If you specify an unacceptable value when manually configuring the Kdump memory reservation, you can click Done to return to the Installation Summary screen. The installer does not generate a warning or error message. Instead, the installer automatically resets the value either to the last known acceptable value or the default value of 512 MB, which enables the installation to succeed. However, because this corrected setting is not displayed on the screen, you might not become aware that your specified value was ignored.

This issue does not occur with the text-based installer, which correctly returns an error if you enter an unacceptable value and prevents you from continuing.

(Bug IDs 31133351, 31182708)

A minor usability error affects the graphical installation program during the configuration of Kdump. If you manually change the default memory size that is reserved for Kdump, the new setting is not displayed when the screen is refreshed. Instead, only the values for the total system memory and usable system memory are displayed. Consequently, the limits for the parameter "Memory to be reserved (Mb)" become unknown for future Kdump configuration.

(Bug IDs 31133287 and 31182699)

A scriplet-related error message might be displayed during an upgrade of an Oracle Linux 8 release to its next version. When you run the dnf update command, an output similar to the following might appear:

  Running scriptlet: tuned-2.13.0-6.0.2.el8.noarch                            
             1089/1089
  Running scriptlet: microcode_ctl-4:20191115-4.el8.x86_64                    
             1089/1089
realpath: weak-updates/kmod-kvdo/vdo/kvdo.ko: No such file or directory
realpath: weak-updates/kmod-kvdo/uds/uds.ko: No such file or directory
dracut: installkernel failed in module kernel-modules-extra
warning: %posttrans(microcode_ctl-4:20191115-4.el8.x86_64) scriptlet failed,
exit status 1

Error in POSTTRANS scriptlet in rpm package microcode_ctl
  Running scriptlet: libgcc-8.3.1-4.5.0.7.el8.x86_64                          
             1089/1089
  Running scriptlet: glibc-common-2.28-101.0.1.el8.x86_64                    
             1089/1089
  Running scriptlet: info-6.5-6.el8.x86_64                                    
             1089/1089

This error message is displayed if you use the Server with GUI environment to install Oracle Linux 8 and then you reboot the server by using RHCK. This installation method installs the kernel dependent, kmod-kvdo package or module, which is a different version in the previous Oracle Linux 8 release.

However, you can safely ignore the message because the kmod-kvdo package is successfully installed during the upgrade process.

(Bug ID 31292199)

Beginning with Oracle Linux 8.1, using the rhnreg_ks command to register a system with the Unbreakable Linux Network (ULN)might fail if the python3-rhn-virtualization-hosts package is installed on the system. This issue has been observed when the libvirtd service is not running.

To work around this issue, ensure that the libvirtd packages are installed on your system and that the service is enabled and running prior to issuing the rhnreg_ks command.

(Bug ID 30366521)

Beginning with Oracle Linux 8.5, when you upgrade Oracle Linux 8 with both the ol8_baseos_latest and ol8_appstream yum repositories enabled, a conflict between the usbguard-1.0.0-2.el8.i686 and usbguard-1.0.0-8.el8.x86_64 packages occurs.

The following error is produced:

Problem: package usbguard-1.0.0-8.el8.x86_64 conflicts with usbguard
provided by usbguard-1.0.0-2.el8.i686
  - cannot install the best candidate for the job
  - problem with installed package usbguard-1.0.0-2.el8.i686
(try to add '--allowerasing' to command line to replace conflicting packages
or '--skip-broken' to skip uninstallable packages or '--nobest' to use not
only best candidate packages)

This conflict occurs because in Oracle Linux 8.6 and later releases, the usbguard-1.0.0-2.el8.i686 and the usbguard-1.0.0-8.el8.x86_64 packages conflict with each other and could no longer be installed together, unlike in previous Oracle Linux 8 releases.

To work around this issue, remove the usbguard-1.0.0-2.el8.i686 package from your Oracle Linux 8 system prior to upgrading to the current release.

(Bug ID 34097708)

While upgrading a system to the current Oracle Linux 8 release, you might encounter a dependency issue if the beignet package exists on the system to be upgraded.

This issue exists specifically in cases where you upgrade systems running Oracle Linux 8.2 or earlier releases to the current Oracle Linux version. In these earlier releases, the beginet package requires earlier versions of the clang-libs package.

However, the beignet package is currently not available for Oracle Linux 8.4 and later Oracle Linux 8 releases. Therefore, the issue does not exist for these cases.

To work around this issue, remove the beignet package from the system prior to upgrading to the current Oracle Linux 8 release.

(Bug ID 31213935)

On new installations of Oracle Linux 8, the ULN registration wizard that presents the options to register with ULN and to use Oracle Ksplice is not displayed on first boot.

As an alternative, you can register with ULN after the installation completes. For instructions, see https://linux.oracle.com/.

(Bug ID 29933974)

To successfully install Oracle Linux 8 on an Oracle VM VirtualBox guest, where the graphical installation program is used and the default Server with GUI environment is selected, you must set the guest to use the VMSVGA graphics controller and configure the guest with at least 64MB of memory. Otherwise, the graphical display is unable to start correctly.

Beginning with Oracle VM VirtualBox 6.0, the VMSVGA graphics controller is the default controller for guests running Linux operating systems. This issue is more likely to appear if install Oracle Linux 8 on an existing guest that was created on an earlier Oracle VM VirtualBox release. To configure Oracle Linux 8 guests, Oracle recommends that you use Oracle VM VirtualBox 6.0 or later.

(Bug ID 30004543)

The Oracle Linux 8.6 installer displays the following error on aarch64 systems that have a multipath-enabled NVMe controller:

Failed to set new efi boot target . This is most likely a kernel or firmware bug.

To work around this issue, disable native multipath support for the installation at boot time by adding the nvme_core.multipath=N command-line argument on the target system.

(Bug IDs 34215333, 31758304)

The Btrfs file system is removed from RHCK in Oracle Linux 8, which means you cannot create or mount this file system when using this kernel. Also, any Btrfs user space packages that are provided are not supported with RHCK.

Support for the Btrfs file system is enabled in UEK R7 and UEK R6. Starting with Oracle Linux 8.3, during an installation, you have the option to create a Btrfs root file system, as well as select Btrfs as the file system type when formatting devices.

For further details about these changes, see the following documentation:

• For information about creating a Btrfs root file system during an installation, see Oracle Linux 8: Installing Oracle Linux.

• For information about managing the Btrfs file system, see Oracle Linux 8: Managing Local File Systems.

• For the latest information about other enhancements that have been made to Btrfs in UEK R6, see Unbreakable Enterprise Kernel: Release Notes for Unbreakable Enterprise Kernel Release 6 Update 3 (5.4.17-2136).

  For information about UEK R7, see Unbreakable Enterprise Kernel: Release Notes for Unbreakable Enterprise Kernel Release 7 (5.15.0-0.30).

The OCFS2 file system is removed from RHCK in Oracle Linux 8, which means you cannot create or mount this file system when using this kernel. Also, OCFS2 user space packages that are provided are not supported with RHCK.

Note that support for OCFS2 file systems is enabled in UEK R7 and UEK R6. For the latest information and other enhancements that have been made to OCFS2 in UEK R6, see Unbreakable Enterprise Kernel: Release Notes for Unbreakable Enterprise Kernel Release 6 Update 3 (5.4.17-2136). See also Unbreakable Enterprise Kernel: Release Notes for Unbreakable Enterprise Kernel Release 7 (5.15.0-0.30).

If a system that is using the ext4 file system is repeatedly or frequently shut down, the file system might become corrupted. This issue is difficult to replicate and is therefore considered to be a corner-case issue. The issue exists in the upstream code and proposed patches are currently under review.

(Bug ID 27547113)

The following errors might be displayed repeatedly when KVM guests are booting on 64-bit AMD hosts:

[   12.474069] amd64_edac_mod: Unknown symbol amd_register_ecc_decoder (err [ 120)
[   12.474083] amd64_edac_mod: Unknown symbol amd_report_gart_errors (err 0)
[   12.852250] amd64_edac_mod: Unknown symbol amd_unregister_ecc_decoder (err 0)
[   12.852297] amd64_edac_mod: Unknown symbol amd_register_ecc_decoder (err 0)
.
.
.

These errors occur because the module code for the kernel erroneously returns -EEXIST for modules that failed to load and are in the process of being removed from the module list. The amd64_edac_mod module will not be loaded in a VM. These errors can be ignored, as they do not impact functionality in any way.

This issue occurs on Oracle Linux 8 hosts that are running RHCK only and is not encountered on UEK R6 hosts.

(Bug ID 29853602)

A bug in the Oracle Linux 8 code causes Retropline support to not be displayed in the output of the modinfo -F retpoline command, even though the CONFIG_RETPOLINE flag is set to Y, for example:

sudo modinfo -F retpoline
/usr/lib/modules/4.18.0-80.el8.x86_64/kernel/sound/usb/usx2y/snd-usb-us122l.ko
.xz

The CONFIG_RETPOLINE=Y flag is still required to add and display Retpoline support. If the parameter is enabled, the kernel builds with a retpoline capable compiler.

To confirm that the CONFIG_RETPOLINE flag is enabled, search for the parameter in the kernel's config-kernel configuration file, for example:

cat /boot/config-5.4.17-2011.7.4.el8uek.x86_64 | grep RETPOLINE.

CONFIG_RETPOLINE=y

(Bug ID 29894295)

Kdump might fail on some AMD hardware that is running the current Oracle Linux release. Impacted hardware includes the AMD EPYC CPU servers.

To work around this issue, modify the /etc/sysconfig/kdump configuration file and remove the iommu=off command-line option from the KDUMP_COMMANDLINE_APPEND variable. Restart the kdump service for the changes to take effect.

(Bug ID 31274238, 34034614, 34211826)

The new LVM dm-writecache caching method has certain limitations that do not exist with the dm-cache method, including the following:

• Cannot attach or detach dm-writecache when a logical volume is active.

• Cannot take a snapshot of a logical volume when the logical volume is using dm-writecache.

• Must use a dm-writecache block size that matches the existing file system block size when attaching dm-writecache to an inactive logical volume.

• Cannot resize a logical volume when dm-writecache is attached to the volume.

• Cannot use pvmove commands on devices that are used with dm-writecache.

• Cannot use logical volumes with dm-writecache when using thin pools or the virtual data optimizer (VDO).

For more information about the dm-writecache caching method, see the File Systems and Storage features section of Oracle Linux 8: Release Notes for Oracle Linux 8.2. See also the lvmcache(7) manual page.