Chapter 11. Known issues

During RHEL installation on IBM Z, udev does not assign predictable interface names to RoCE cards enumerated by FID

If you start a RHEL 8.7 or later installation with the net.naming-scheme=rhel-8.7 kernel command-line option, the udev device manager on the RHEL installation media ignores this setting for RoCE cards enumerated by the function identifier (FID). As a consequence, udev assigns unpredictable interface names to these devices. There is no workaround during the installation, but you can configure the feature after the installation. For further details, see Determining a predictable RoCE device name on the IBM Z platform.

Installation fails on IBM Power 10 systems with LPAR and secure boot enabled

RHEL installer is not integrated with static key secure boot on IBM Power 10 systems. Consequently, when logical partition (LPAR) is enabled with the secure boot option, the installation fails with the error, Unable to proceed with RHEL-x.x Installation.

Unexpected SELinux policies on systems where Anaconda is running as an application

When Anaconda is running as an application on an already installed system (for example to perform another installation to an image file using the –image anaconda option), the system is not prohibited to modify the SELinux types and attributes during installation. As a consequence, certain elements of SELinux policy might change on the system where Anaconda is running.

The auth and authconfig Kickstart commands require the AppStream repository

The authselect-compat package is required by the auth and authconfig Kickstart commands during installation. Without this package, the installation fails if auth or authconfig are used. However, by design, the authselect-compat package is only available in the AppStream repository.

The reboot --kexec and inst.kexec commands do not provide a predictable system state

Performing a RHEL installation with the reboot --kexec Kickstart command or the inst.kexec kernel boot parameters do not provide the same predictable system state as a full reboot. As a consequence, switching to the installed system without rebooting can produce unpredictable results.

The USB CD-ROM drive is not available as an installation source in Anaconda

Installation fails when the USB CD-ROM drive is the source for it and the Kickstart ignoredisk --only-use= command is specified. In this case, Anaconda cannot find and use this source disk.

Network access is not enabled by default in the installation program

Several installation features require network access, for example, registration of a system using the Content Delivery Network (CDN), NTP server support, and network installation sources. However, network access is not enabled by default, and as a result, these features cannot be used until network access is enabled.

Hard drive partitioned installations with iso9660 filesystem fails

You cannot install RHEL on systems where the hard drive is partitioned with the iso9660 filesystem. This is due to the updated installation code that is set to ignore any hard disk containing a iso9660 file system partition. This happens even when RHEL is installed without using a DVD.

IBM Power systems with HASH MMU mode fail to boot with memory allocation failures

IBM Power Systems with HASH memory allocation unit (MMU) mode support kdump up to a maximum of 192 cores. Consequently, the system fails to boot with memory allocation failures if kdump is enabled on more than 192 cores. This limitation is due to RMA memory allocations during early boot in HASH MMU mode. To work around this problem, use the Radix MMU mode with fadump enabled instead of using kdump.

RHEL for Edge installer image fails to create mount points when installing an rpm-ostree payload

When deploying rpm-ostree payloads, used for example in a RHEL for Edge installer image, the installer does not properly create some mount points for custom partitions. As a consequence, the installation is aborted with the following error:

Images built with the stig profile remediation fails to boot with FIPS error

FIPS mode is not supported by RHEL image builder. When using RHEL image builder customized with the xccdf_org.ssgproject.content_profile_stig profile remediation, the system fails to boot with the following error:

sshd -T provides inaccurate information about Ciphers, MACs and KeX algorithms

The output of the sshd -T command does not contain the system-wide crypto policy configuration or other options that could come from an environment file in /etc/sysconfig/sshd and that are applied as arguments on the sshd command. This occurs because the upstream OpenSSH project did not support the Include directive to support Red-Hat-provided cryptographic defaults in RHEL 8. Crypto policies are applied as command-line arguments to the sshd executable in the sshd.service unit during the service’s start by using an EnvironmentFile. To work around the problem, use the source command with the environment file and pass the crypto policy as an argument to the sshd command, as in sshd -T $CRYPTO_POLICY. For additional information, see Ciphers, MACs or KeX algorithms differ from sshd -T to what is provided by current crypto policy level. As a result, the output from sshd -T matches the currently configured crypto policy.

RHV hypervisor may not work correctly when hardening the system during installation

When installing Red Hat Virtualization Hypervisor (RHV-H) and applying the Red Hat Enterprise Linux 8 STIG profile, OSCAP Anaconda Add-on may harden the system as RHEL instead of RVH-H and remove essential packages for RHV-H. Consequently, the RHV hypervisor may not work. To work around the problem, install the RHV-H system without applying any profile hardening, and after the installation is complete, apply the profile by using OpenSCAP. As a result, the RHV hypervisor works correctly.

CVE OVAL feeds are now only in the compressed format, and data streams are not in the SCAP 1.3 standard

Red Hat provides CVE OVAL feeds in the bzip2-compressed format and are no longer available in the XML file format. Because referencing compressed content is not standardized in the Security Content Automation Protocol (SCAP) 1.3 specification, third-party SCAP scanners can have problems scanning rules that use the feed.

Certain Rsyslog priority strings do not work correctly

Support for the GnuTLS priority string for imtcp that allows fine-grained control over encryption is not complete. Consequently, the following priority strings do not work properly in the Rsyslog remote logging application:

Server with GUI and Workstation installations are not possible with CIS Server profiles

The CIS Server Level 1 and Level 2 security profiles are not compatible with the Server with GUI and Workstation software selections. As a consequence, a RHEL 8 installation with the Server with GUI software selection and CIS Server profiles is not possible. An attempted installation using the CIS Server Level 1 or Level 2 profiles and either of these software selections will generate the error message:

Kickstart uses org_fedora_oscap instead of com_redhat_oscap in RHEL 8

The Kickstart references the Open Security Content Automation Protocol (OSCAP) Anaconda add-on as org_fedora_oscap instead of com_redhat_oscap, which might cause confusion. This is necessary to keep compatibility with Red Hat Enterprise Linux 7.

libvirt overrides xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_forwarding

The libvirt virtualization framework enables IPv4 forwarding whenever a virtual network with a forward mode of route or nat is started. This overrides the configuration by the xccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_forwarding rule, and subsequent compliance scans report the fail result when assessing this rule.

The fapolicyd utility incorrectly allows executing changed files

Correctly, the IMA hash of a file should update after any change to the file, and fapolicyd should prevent execution of the changed file. However, this does not happen due to differences in IMA policy setup and in file hashing by the evctml utility. As a result, the IMA hash is not updated in the extended attribute of a changed file. Consequently, fapolicyd incorrectly allows the execution of the changed file.

OpenSSL in FIPS mode accepts only specific D-H parameters

In FIPS mode, TLS clients that use OpenSSL return a bad dh value error and abort TLS connections to servers that use manually generated parameters. This is because OpenSSL, when configured to work in compliance with FIPS 140-2, works only with Diffie-Hellman parameters compliant to NIST SP 800-56A rev3 Appendix D (groups 14, 15, 16, 17, and 18 defined in RFC 3526 and with groups defined in RFC 7919). Also, servers that use OpenSSL ignore all other parameters and instead select known parameters of similar size. To work around this problem, use only the compliant groups.

crypto-policies incorrectly allow Camellia ciphers

The RHEL 8 system-wide cryptographic policies should disable Camellia ciphers in all policy levels, as stated in the product documentation. However, the Kerberos protocol enables the ciphers by default.

OpenSC might not detect CardOS V5.3 card objects correctly

The OpenSC toolkit does not correctly read cache from different PKCS #15 file offsets used in some CardOS V5.3 cards. Consequently, OpenSC might not be able to list card objects and prevent using them from different applications.

Smart-card provisioning process through OpenSC pkcs15-init does not work properly

The file_caching option is enabled in the default OpenSC configuration, and the file caching functionality does not handle some commands from the pkcs15-init tool properly. Consequently, the smart-card provisioning process through OpenSC fails.

Connections to servers with SHA-1 signatures do not work with GnuTLS

SHA-1 signatures in certificates are rejected by the GnuTLS secure communications library as insecure. Consequently, applications that use GnuTLS as a TLS backend cannot establish a TLS connection to peers that offer such certificates. This behavior is inconsistent with other system cryptographic libraries.

libselinux-python is available only through its module

The libselinux-python package contains only Python 2 bindings for developing SELinux applications and it is used for backward compatibility. For this reason, libselinux-python is no longer available in the default RHEL 8 repositories through the yum install libselinux-python command.

udica processes UBI 8 containers only when started with --env container=podman

The Red Hat Universal Base Image 8 (UBI 8) containers set the container environment variable to the oci value instead of the podman value. This prevents the udica tool from analyzing a container JavaScript Object Notation (JSON) file.

Negative effects of the default logging setup on performance

The default logging environment setup might consume 4 GB of memory or even more and adjustments of rate-limit values are complex when systemd-journald is running with rsyslog.

SELINUX=disabled in /etc/selinux/config does not work properly

Disabling SELinux using the SELINUX=disabled option in the /etc/selinux/config results in a process in which the kernel boots with SELinux enabled and switches to disabled mode later in the boot process. This might cause memory leaks.

IKE over TCP connections do not work on custom TCP ports

The tcp-remoteport Libreswan configuration option does not work properly. Consequently, an IKE over TCP connection cannot be established when a scenario requires specifying a non-default TCP port.

scap-security-guide cannot configure termination of idle sessions

Even though the sshd_set_idle_timeout rule still exists in the data stream, the former method for idle session timeout of configuring sshd is no longer available. Therefore, the rule is marked as not applicable and cannot harden anything. Other methods for configuring idle session termination, such as systemd (Logind), are also not available. As a consequence, scap-security-guide cannot configure the system to reliably disconnect idle sessions after a certain amount of time.

The OSCAP Anaconda add-on does not fetch tailored profiles in the graphical installation

The OSCAP Anaconda add-on does not provide an option to select or deselect tailoring of security profiles in the RHEL graphical installation. Starting from RHEL 8.8, the add-on does not take tailoring into account by default when installing from archives or RPM packages. Consequently, the installation displays the following error message instead of fetching an OSCAP tailored profile:

OpenSCAP memory-consumption problems

On systems with limited memory, the OpenSCAP scanner might stop prematurely or it might not generate the results files. To work around this problem, you can customize the scanning profile to deselect rules that involve recursion over the entire / file system:

Rebuilding the rpm database assigns incorrect SELinux labeling

Rebuilding the rpm database with the rpmdb --rebuilddb command assigns incorrect SELinux labels to the rpm database files. As a consequence, some services that use the rpm database might not work correctly. To work around this problem after rebuilding the database, relabel the database by using the restorecon -Rv /var/lib/rpm command.

ANSSI BP28 HP SCAP rules for Audit are incorrectly used on the 64-bit ARM architecture

The ANSSI BP28 High profile in the SCAP Security Guide (SSG) contains the following security content automation protocol (SCAP) rules that configure the Linux Audit subsystem but are invalid on the 64-bit ARM architecture:

Remediating service-related rules during kickstart installations might fail

During a kickstart installation, the OpenSCAP utility sometimes incorrectly shows that a service enable or disable state remediation is not needed. Consequently, OpenSCAP might set the services on the installed system to a non-compliant state. As a workaround, you can scan and remediate the system after the kickstart installation. This will fix the service-related issues.

syspurpose addons have no effect on the subscription-manager attach --auto output

In Red Hat Enterprise Linux 8, four attributes of the syspurpose command-line tool have been added: role,usage, service_level_agreement and addons. Currently, only role, usage and service_level_agreement affect the output of running the subscription-manager attach --auto command. Users who attempt to set values to the addons argument will not observe any effect on the subscriptions that are auto-attached.

cr_compress_file_with_stat() can cause a memory leak

The createrepo_c C library has the API cr_compress_file_with_stat() function. This function is declared with char **dst as a second parameter. Depending on its other parameters, cr_compress_file_with_stat() either uses dst as an input parameter, or uses it to return an allocated string. This unpredictable behavior can cause a memory leak, because it does not inform the user when to free dst contents.

YUM transactions reported as successful when a scriptlet fails

Since RPM version 4.6, post-install scriptlets are allowed to fail without being fatal to the transaction. This behavior propagates up to YUM as well. This results in scriptlets which might occasionally fail while the overall package transaction reports as successful.

ipmitool is incompatible with certain server platforms

The ipmitool utility serves for monitoring, configuring, and managing devices that support the Intelligent Platform Management Interface (IPMI). The current version of ipmitool uses Cipher Suite 17 by default instead of the previous Cipher Suite 3. Consequently, ipmitool fails to communicate with certain bare metal nodes that announced support for Cipher Suite 17 during negotiation, but do not actually support this cipher suite. As a result, ipmitool aborts with the no matching cipher suite error message.

ReaR fails to recreate a volume group when you do not use clean disks for restoring

ReaR fails to perform recovery when you want to restore to disks that contain existing data.

coreutils might report misleading EPERM error codes

GNU Core Utilities (coreutils) started using the statx() system call. If a seccomp filter returns an EPERM error code for unknown system calls, coreutils might consequently report misleading EPERM error codes because EPERM can not be distinguished from the actual Operation not permitted error returned by a working statx() syscall.

The %vmeff metric from the sysstat package displays incorrect values

The sysstat package provides the %vmeff metric to measure the page reclaim efficiency. The values of the %vmeff column returned by the sar -B command are incorrect because sysstat does not parse all relevant /proc/vmstat values provided by later kernel versions. To work around this problem, you can calculate the %vmeff value manually from the /proc/vmstat file. For details, see Why the sar(1) tool reports %vmeff values beyond 100 % in RHEL 8 and RHEL 9?

Postfix TLS fingerprint algorithm in the FIPS mode needs to be changed to SHA-256

By default in RHEL 8, postfix uses MD5 fingerprints with the TLS for backward compatibility. But in the FIPS mode, the MD5 hashing function is not available, which may cause TLS to incorrectly function in the default postfix configuration. To work around this problem, the hashing function needs to be changed to SHA-256 in the postfix configuration file.

The brltty package is not multilib compatible

It is not possible to have both 32-bit and 64-bit versions of the brltty package installed. You can either install the 32-bit (brltty.i686) or the 64-bit (brltty.x86_64) version of the package. The 64-bit version is recommended.

RoCE interfaces lose their IP settings due to an unexpected change of the network interface name

The RDMA over Converged Ethernet (RoCE) interfaces lose their IP settings due to an unexpected change of the network interface name if both conditions are met:

Systems with the IPv6_rpfilter option enabled experience low network throughput

Systems with the IPv6_rpfilter option enabled in the firewalld.conf file currently experience suboptimal performance and low network throughput in high traffic scenarios, such as 100 Gbps links. To work around the problem, disable the IPv6_rpfilter option. To do so, add the following line in the /etc/firewalld/firewalld.conf file.

The kernel ACPI driver reports it has no access to a PCIe ECAM memory region

The Advanced Configuration and Power Interface (ACPI) table provided by firmware does not define a memory region on the PCI bus in the Current Resource Settings (_CRS) method for the PCI bus device. Consequently, the following warning message occurs during the system boot:

The tuned-adm profile powersave command causes the system to become unresponsive

Executing the tuned-adm profile powersave command leads to an unresponsive state of the Penguin Valkyrie 2000 2-socket systems with the older Thunderx (CN88xx) processors. Consequently, reboot the system to resume working. To work around this problem, avoid using the powersave profile if your system matches the mentioned specifications.

The HP NMI watchdog does not always generate a crash dump

In certain cases, the hpwdt driver for the HP NMI watchdog is not able to claim a non-maskable interrupt (NMI) generated by the HPE watchdog timer because the NMI was instead consumed by the perfmon driver.

Reloading an identical crash extension may cause segmentation faults

When you load a copy of an already loaded crash extension file, it might trigger a segmentation fault. Currently, the crash utility detects if an original file has been loaded. Consequently, due to two identical files co-existing in the crash utility, a namespace collision occurs, which triggers the crash utility to cause a segmentation fault.

Connections fail when attaching a virtual function to virtual machine

Pensando network cards that use the ionic device driver silently accept VLAN tag configuration requests and attempt configuring network connections while attaching network virtual functions (VF) to a virtual machine (VM). Such network connections fail as this feature is not yet supported by the card’s firmware.

The OPEN MPI library may trigger run-time failures with default PML

In OPEN Message Passing Interface (OPEN MPI) implementation 4.0.x series, Unified Communication X (UCX) is the default point-to-point communicator (PML). The later versions of OPEN MPI 4.0.x series deprecated openib Byte Transfer Layer (BTL).

vmcore capture fails after memory hot-plug or unplug operation

After performing the memory hot-plug or hot-unplug operation, the event comes after updating the device tree which contains memory layout information. Thereby the makedumpfile utility tries to access a non-existent physical address. The problem appears if all of the following conditions meet:

Using irqpoll causes vmcore generation failure

Due to an existing problem with the nvme driver on the 64-bit ARM architecture that run on the Amazon Web Services Graviton 1 processor, causes vmcore generation to fail when you provide the irqpoll kernel command line parameter to the first kernel. Consequently, no vmcore file is dumped in the /var/crash/ directory upon a kernel crash. To work around this problem:

Hardware certification of the real-time kernel on systems with large core-counts might require passing the skew-tick=1 boot parameter

Large or moderate sized systems with numerous sockets and large core-counts can experience latency spikes due to lock contentions on xtime_lock, which is used in the timekeeping system. As a consequence, latency spikes and delays in hardware certifications might occur on multiprocessing systems. As a workaround, you can offset the timer tick per CPU to start at a different time by adding the skew_tick=1 boot parameter.

Debug kernel fails to boot in crash capture environment on RHEL 8

Due to the memory-intensive nature of the debug kernel, a problem occurs when the debug kernel is in use and a kernel panic is triggered. As a consequence, the debug kernel is not able to boot as the capture kernel and a stack trace is generated instead. To work around this problem, increase the crash kernel memory as required. As a result, the debug kernel boots successfully in the crash capture environment.

Allocating crash kernel memory fails at boot time

On some Ampere Altra systems, allocating the crash kernel memory during boot fails when the 32-bit region is disabled in BIOS settings. Consequently, the kdump service fails to start. This is caused by memory fragmentation in the region below 4 GB with no fragment being large enough to contain the crash kernel memory.

The QAT manager leaves no spare device for LKCF

The Intel® QuickAssist Technology (QAT) manager (qatmgr) is a user space process, which by default uses all QAT devices in the system. As a consequence, there are no QAT devices left for the Linux Kernel Cryptographic Framework (LKCF). There is no need to work around this situation, as this behavior is expected and a majority of users will use acceleration from the user space.

The Solarflare fails to create maximum number of virtual functions (VFs)

The Solarflare NICs fail to create a maximum number of VFs due to insufficient resources. You can check the maximum number of VFs that a PCIe device can create in the /sys/bus/pci/devices/PCI_ID/sriov_totalvfs file. To workaround this problem, you can either adjust the number of VFs or the VF MSI interrupt value to a lower value, either from Solarflare Boot Manager on startup, or using Solarflare sfboot utility. The default VF MSI interrupt value is 8.

Using page_poison=1 can cause a kernel crash

When using page_poison=1 as the kernel parameter on firmware with faulty EFI implementation, the operating system can cause the kernel to crash. By default, this option is disabled and it is not recommended to enable it, especially in production systems.

The iwl7260-firmware breaks Wi-Fi on Intel Wi-Fi 6 AX200, AX210, and Lenovo ThinkPad P1 Gen 4

After updating the iwl7260-firmware or iwl7260-wifi driver to the version provided by RHEL 8.7 and later, the hardware gets into an incorrect internal state. reports its state incorrectly. Consequently, Intel Wifi 6 cards may not work and display the error message:

Secure boot on IBM Power Systems does not support migration

Currently, on IBM Power Systems, logical partition (LPAR) does not boot after successful physical volume (PV) migration. As a result, any type of automated migration with secure boot enabled on a partition fails.

weak-modules from kmod fails to work with module inter-dependencies

The weak-modules script provided by the kmod package determines which modules are kABI-compatible with installed kernels. However, while checking modules' kernel compatibility, weak-modules processes modules symbol dependencies from higher to lower release of the kernel for which they were built. As a consequence, modules with inter-dependencies built against different kernel releases might be interpreted as non-compatible, and therefore the weak-modules script fails to work in this scenario.

kdump in Ampere Altra servers enters the OOM state

The firmware in Ampere Altra and Altra Max servers currently causes the kernel to allocate too many event, interrupt and command queues, which consumes too much memory. As a consequence, the kdump kernel enters the Out of memory (OOM) state.

LVM mirror devices that store a LUKS volume sometimes become unresponsive

Mirrored LVM devices with a segment type of mirror that store a LUKS volume might become unresponsive under certain conditions. The unresponsive devices reject all I/O operations.

The /boot file system cannot be placed on LVM

You cannot place the /boot file system on an LVM logical volume. This limitation exists for the following reasons:

LVM no longer allows creating volume groups with mixed block sizes

LVM utilities such as vgcreate or vgextend no longer allow you to create volume groups (VGs) where the physical volumes (PVs) have different logical block sizes. LVM has adopted this change because file systems fail to mount if you extend the underlying logical volume (LV) with a PV of a different block size.

Limitations of LVM writecache

The writecache LVM caching method has the following limitations, which are not present in the cache method:

Device-mapper multipath is not supported when using NVMe/TCP driver.

The use of device-mapper multipath on top of NVMe/TCP devices can cause reduced performance and error handling. To avoid this problem, use native NVMe multipath instead of DM multipath tools. For RHEL 8, you can add the option nvme_core.multipath=Y to the kernel command line.

The blk-availability systemd service deactivates complex device stacks

In systemd, the default block deactivation code does not always handle complex stacks of virtual block devices correctly. In some configurations, virtual devices might not be removed during the shutdown, which causes error messages to be logged. To work around this problem, deactivate complex block device stacks by executing the following command:

XFS quota warnings are triggered too often

Using the quota timer results in quota warnings triggering too often, which causes soft quotas to be enforced faster than they should. To work around this problem, do not use soft quotas, which will prevent triggering warnings. As a result, the amount of warning messages will not enforce soft quota limit anymore, respecting the configured timeout.

Creating virtual Python 3.11 environments fails when using the virtualenv utility

The virtualenv utility in RHEL 8, provided by the python3-virtualenv package, is not compatible with Python 3.11. An attempt to create a virtual environment by using virtualenv will fail with the following error message:

python3.11-lxml does not provide the lxml.isoschematron submodule

The python3.11-lxml package is distributed without the lxml.isoschematron submodule because it is not under an open source license. The submodule implements ISO Schematron support. As an alternative, pre-ISO-Schematron validation is available in the lxml.etree.Schematron class. The remaining content of the python3.11-lxml package is unaffected.

PAM plug-in version 1.0 does not work in MariaDB

MariaDB 10.3 provides the Pluggable Authentication Modules (PAM) plug-in version 1.0. MariaDB 10.5 provides the plug-in versions 1.0 and 2.0, version 2.0 is the default.

Symbol conflicts between OpenLDAP libraries might cause crashes in httpd

When both the libldap and libldap_r libraries provided by OpenLDAP are loaded and used within a single process, symbol conflicts between these libraries might occur. Consequently, Apache httpd child processes using the PHP ldap extension might terminate unexpectedly if the mod_security or mod_auth_openidc modules are also loaded by the httpd configuration.

getpwnam() might fail when called by a 32-bit application

When a user of NIS uses a 32-bit application that calls the getpwnam() function, the call fails if the nss_nis.i686 package is missing. To work around this problem, manually install the missing package by using the yum install nss_nis.i686 command.

Actions required when running Samba as a print server and updating from RHEL 8.4 and earlier

With this update, the samba package no longer creates the /var/spool/samba/ directory. If you use Samba as a print server and use /var/spool/samba/ in the [printers] share to spool print jobs, SELinux prevents Samba users from creating files in this directory. Consequently, print jobs fail and the auditd service logs a denied message in /var/log/audit/audit.log. To avoid this problem after updating your system from 8.4 and earlier:

Using the cert-fix utility with the --agent-uid pkidbuser option breaks Certificate System

Using the cert-fix utility with the --agent-uid pkidbuser option corrupts the LDAP configuration of Certificate System. As a consequence, Certificate System might become unstable and manual steps are required to recover the system.

FIPS mode does not support using a shared secret to establish a cross-forest trust

Establishing a cross-forest trust using a shared secret fails in FIPS mode because NTLMSSP authentication is not FIPS-compliant. To work around this problem, authenticate with an Active Directory (AD) administrative account when establishing a trust between an IdM domain with FIPS mode enabled and an AD domain.

Downgrading authselect after the rebase to version 1.2.2 breaks system authentication

The authselect package has been rebased to the latest upstream version 1.2.2. Downgrading authselect is not supported and breaks system authentication for all users, including root.

IdM to AD cross-realm TGS requests fail

The Privilege Attribute Certificate (PAC) information in IdM Kerberos tickets is now signed with AES SHA-2 HMAC encryption, which is not supported by Active Directory (AD).

Potential risk when using the default value for ldap_id_use_start_tls option

When using ldap:// without TLS for identity lookups, it can pose a risk for an attack vector. Particularly a man-in-the-middle (MITM) attack which could allow an attacker to impersonate a user by altering, for example, the UID or GID of an object returned in an LDAP search.

pki-core-debuginfo update from RHEL 8.6 to RHEL 8.7 or later fails

Updating the pki-core-debuginfo package from RHEL 8.6 to RHEL 8.7 or later fails. To work around this problem, run the following commands:

Migrated IdM users might be unable to log in due to mismatching domain SIDs

If you have used the ipa migrate-ds script to migrate users from one IdM deployment to another, those users might have problems using IdM services because their previously existing Security Identifiers (SIDs) do not have the domain SID of the current IdM environment. For example, those users can retrieve a Kerberos ticket with the kinit utility, but they cannot log in. To work around this problem, see the following Knowledgebase article: Migrated IdM users unable to log in due to mismatching domain SIDs.

IdM in FIPS mode does not support using the NTLMSSP protocol to establish a two-way cross-forest trust

Establishing a two-way cross-forest trust between Active Directory (AD) and Identity Management (IdM) with FIPS mode enabled fails because the New Technology LAN Manager Security Support Provider (NTLMSSP) authentication is not FIPS-compliant. IdM in FIPS mode does not accept the RC4 NTLM hash that the AD domain controller uses when attempting to authenticate.

IdM Vault encryption and decryption fails in FIPS mode

The OpenSSL RSA-PKCS1v15 padding encryption is blocked if FIPS mode is enabled. Consequently, Identity Management (IdM) Vaults fail to work correctly as IdM is currently using the PKCS1v15 padding for wrapping the session key with the transport certificate.

Incorrect warning when setting expiration dates for a Kerberos principal

If you set a password expiration date for a Kerberos principal, the current timestamp is compared to the expiration timestamp using a 32-bit signed integer variable. If the expiration date is more than 68 years in the future, it causes an integer variable overflow resulting in the following warning message being displayed:

Disabling flatpak repositories from Software Repositories is not possible

Currently, it is not possible to disable or remove flatpak repositories in the Software Repositories tool in the GNOME Software utility.

Generation 2 RHEL 8 virtual machines sometimes fail to boot on Hyper-V Server 2016 hosts

When using RHEL 8 as the guest operating system on a virtual machine (VM) running on a Microsoft Hyper-V Server 2016 host, the VM in some cases fails to boot and returns to the GRUB boot menu. In addition, the following error is logged in the Hyper-V event log:

Drag-and-drop does not work between desktop and applications

Due to a bug in the gnome-shell-extensions package, the drag-and-drop functionality does not currently work between desktop and applications. Support for this feature will be added back in a future release.

WebKitGTK fails to display web pages on IBM Z

The WebKitGTK web browser engine fails when trying to display web pages on the IBM Z architecture. The web page remains blank and the WebKitGTK process terminates unexpectedly.

The radeon driver fails to reset hardware correctly

The radeon kernel driver currently does not reset hardware in the kexec context correctly. Instead, radeon falls over, which causes the rest of the kdump service to fail.

Multiple HDR displays on a single MST topology may not power on

On systems using NVIDIA Turing GPUs with the nouveau driver, using a DisplayPort hub (such as a laptop dock) with multiple monitors which support HDR plugged into it may result in failure to turn on. This is due to the system erroneously thinking there is not enough bandwidth on the hub to support all of the displays.

GUI in ESXi might crash due to low video memory

The graphical user interface (GUI) on RHEL virtual machines (VMs) in the VMware ESXi 7.0.1 hypervisor with vCenter Server 7.0.1 requires a certain amount of video memory. If you connect multiple consoles or high-resolution monitors to the VM, the GUI requires at least 16 MB of video memory. If you start the GUI with less video memory, the GUI might terminate unexpectedly.

VNC Viewer displays wrong colors with the 16-bit color depth on IBM Z

The VNC Viewer application displays wrong colors when you connect to a VNC session on an IBM Z server with the 16-bit color depth.

Unable to run graphical applications using sudo command

When trying to run graphical applications as a user with elevated privileges, the application fails to open with an error message. The failure happens because Xwayland is restricted by the Xauthority file to use regular user credentials for authentication.

Hardware acceleration is not supported on ARM

Built-in graphics drivers do not support hardware acceleration or the Vulkan API on the 64-bit ARM architecture.

Using the RHEL system role with Ansible 2.9 can display a warning about using dnf with the command module

Since RHEL 8.8, the RHEL system roles no longer use the warn parameter in with the dnf module because this parameter was removed in Ansible Core 2.14. However, if you use the latest rhel-system-roles package still with Ansible 2.9 and a role installs a package, one of the following warnings can be displayed:

Unable to manage localhost by using the localhost hostname in the playbook or inventory

With the inclusion of the ansible-core 2.13 package in RHEL, if you are running Ansible on the same host you manage your nodes, you cannot do it by using the localhost hostname in your playbook or inventory. This happens because ansible-core 2.13 uses the python38 module, and many of the libraries are missing, for example, blivet for the storage role, gobject for the network role. To workaround this problem, if you are already using the localhost hostname in your playbook or inventory, you can add a connection, by using ansible_connection=local, or by creating an inventory file that lists localhost with the ansible_connection=local option. With that, you are able to manage resources on localhost. For more details, see the article RHEL system roles playbooks fail when run on localhost.

The rhc system role fails on already registered systems when rhc_auth contains activation keys

Executing playbook files on already registered systems fails if activation keys are specified for the rhc_auth parameter. To workaround this issue, do not specify activation keys when executing the playbook file on the already registered system.

Using a large number of queues might cause Windows virtual machines to fail

Windows virtual machines (VMs) might fail when the virtual Trusted Platform Module (vTPM) device is enabled and the multi-queue virtio-net feature is configured to use more than 250 queues.

The Milan VM CPU type is sometimes not available on AMD Milan systems

On certain AMD Milan systems, the Enhanced REP MOVSB (erms) and Fast Short REP MOVSB (fsrm) feature flags are disabled in the BIOS by default. Consequently, the Milan CPU type might not be available on these systems. In addition, VM live migration between Milan hosts with different feature flag settings might fail. To work around these problems, manually turn on erms and fsrm in the BIOS of your host.

SMT CPU topology is not detected by VMs when using host passthrough mode on AMD EPYC

When a virtual machine (VM) boots with the CPU host passthrough mode on an AMD EPYC host, the TOPOEXT CPU feature flag is not present. Consequently, the VM is not able to detect a virtual CPU topology with multiple threads per core. To work around this problem, boot the VM with the EPYC CPU model instead of host passthrough.

Attaching LUN devices to virtual machines using virtio-blk does not work

The q35 machine type does not support transitional virtio 1.0 devices, and RHEL 8 therefore lacks support for features that were deprecated in virtio 1.0. In particular, it is not possible on a RHEL 8 host to send SCSI commands from virtio-blk devices. As a consequence, attaching a physical disk as a LUN device to a virtual machine fails when using the virtio-blk controller.

Virtual machines sometimes fail to start when using many virtio-blk disks

Adding a large number of virtio-blk devices to a virtual machine (VM) may exhaust the number of interrupt vectors available in the platform. If this occurs, the VM’s guest OS fails to boot, and displays a dracut-initqueue[392]: Warning: Could not boot error.

Virtual machines with iommu_platform=on fail to start on IBM POWER

RHEL 8 currently does not support the iommu_platform=on parameter for virtual machines (VMs) on IBM POWER system. As a consequence, starting a VM with this parameter on IBM POWER hardware results in the VM becoming unresponsive during the boot process.

IBM POWER hosts now work correctly when using the ibmvfc driver

When running RHEL 8 on a PowerVM logical partition (LPAR), a variety of errors could previously occur due to problems with the ibmvfc driver. As a consequence, a kernel panic triggered on the host under certain circumstances, such as:

Using perf kvm record on IBM POWER Systems can cause the VM to crash

When using a RHEL 8 host on the little-endian variant of IBM POWER hardware, using the perf kvm record command to collect trace event samples for a KVM virtual machine (VM) in some cases results in the VM becoming unresponsive. This situation occurs when:

Windows Server 2016 virtual machines with Hyper-V enabled fail to boot when using certain CPU models

Currently, it is not possible to boot a virtual machine (VM) that uses Windows Server 2016 as the guest operating system, has the Hyper-V role enabled, and uses one of the following CPU models:

Migrating a POWER9 guest from a RHEL 7-ALT host to RHEL 8 fails

Currently, migrating a POWER9 virtual machine from a RHEL 7-ALT host system to RHEL 8 becomes unresponsive with a Migration status: active status.

Using virt-customize sometimes causes guestfs-firstboot to fail

After modifying a virtual machine (VM) disk image using the virt-customize utility, the guestfs-firstboot service in some cases fails due to incorrect SELinux permissions. This causes a variety of problems during VM startup, such as failing user creation or system registration.

Deleting a forward interface from a macvtap virtual network resets all connection counts of this network

Currently, deleting a forward interface from a macvtap virtual network with multiple forward interfaces also resets the connection status of the other forward interfaces of the network. As a consequence, the connection information in the live network XML is incorrect. Note, however, that this does not affect the functionality of the virtual network. To work around the issue, restart the libvirtd service on your host.

Virtual machines with SLOF fail to boot in netcat interfaces

When using a netcat (nc) interface to access the console of a virtual machine (VM) that is currently waiting at the Slimline Open Firmware (SLOF) prompt, the user input is ignored and VM stays unresponsive. To work around this problem, use the nc -C option when connecting to the VM, or use a telnet interface instead.

Attaching mediated devices to virtual machines in virt-manager in some cases fails

The virt-manager application is currently able to detect mediated devices, but cannot recognize whether the device is active. As a consequence, attempting to attach an inactive mediated device to a running virtual machine (VM) using virt-manager fails. Similarly, attempting to create a new VM that uses an inactive mediated device fails with a device not found error.

RHEL 9 virtual machines fail to boot in POWER8 compatibility mode

Currently, booting a virtual machine (VM) that runs RHEL 9 as its guest operating system fails if the VM also uses CPU configuration similar to the following:

SUID and SGID are not cleared automatically on virtiofs

When you run the virtiofsd service with the killpriv_v2 feature, your system may not automatically clear the SUID and SGID permissions after performing some file-system operations. Consequently, not clearing the permissions might cause a potential security threat. To work around this issue, disable the killpriv_v2 feature by entering the following command:

Restarting the OVS service on a host might block network connectivity on its running VMs

When the Open vSwitch (OVS) service restarts or crashes on a host, virtual machines (VMs) that are running on this host cannot recover the state of the networking device. As a consequence, VMs might be completely unable to receive packets.

NFS failure during VM migration causes migration failure and source VM coredump

Currently, if the NFS service or server is shut down during virtual machine (VM) migration, the source VM’s QEMU is unable to reconnect to the NFS server when it starts running again. As a result, the migration fails and a coredump is initiated on the source VM. Currently, there is no workaround available.

nodedev-dumpxml does not list attributes correctly for certain mediated devices

Currently, the nodedev-dumpxml does not list attributes correctly for mediated devices that were created using the nodedev-create command. To work around this problem, use the nodedev-define and nodedev-start commands instead.

Starting a VM with an NVIDIA A16 GPU sometimes causes the host GPU to stop working

Currently, if you start a VM that uses an NVIDIA A16 GPU passthrough device, the NVIDIA A16 GPU physical device on the host system in some cases stops working.

Setting static IP in a RHEL virtual machine on a VMware host does not work

Currently, when using RHEL as a guest operating system of a virtual machine (VM) on a VMware host, the DatasourceOVF function does not work correctly. As a consequence, if you use the cloud-init utility to set the VM’s network to static IP and then reboot the VM, the VM’s network will be changed to DHCP.

kdump sometimes does not start on Azure and Hyper-V

On RHEL 8 guest operating systems hosted on the Microsoft Azure or Hyper-V hypervisors, starting the kdump kernel in some cases fails when post-exec notifiers are enabled.

The SCSI host address sometimes changes when booting a Hyper-V VM with multiple guest disks

Currently, when booting a RHEL 8 virtual machine (VM) on the Hyper-V hypervisor, the host portion of the Host, Bus, Target, Lun (HBTL) SCSI address in some cases changes. As a consequence, automated tasks set up with the HBTL SCSI identification or device node in the VM do not work consistently. This occurs if the VM has more than one disk or if the disks have different sizes.

RHEL instances on Azure fail to boot if provisioned by cloud-init and configured with an NFSv3 mount entry

Currently, booting a RHEL virtual machine (VM) on the Microsoft Azure cloud platform fails if the VM was provisioned by the cloud-init tool and the guest operating system of the VM has an NFSv3 mount entry in the /etc/fstab file.

The getattachment command fails to download multiple attachments at once

The redhat-support-tool command offers the getattachment subcommand for downloading attachments. However, getattachment is currently only able to download a single attachment and fails to download multiple attachments.

redhat-support-tool does not work with the FUTURE crypto policy

Because a cryptographic key used by a certificate on the Customer Portal API does not meet the requirements by the FUTURE system-wide cryptographic policy, the redhat-support-tool utility does not work with this policy level at the moment.

Timeout when running sos report on IBM Power Systems, Little Endian

When running the sos report command on IBM Power Systems, Little Endian with hundreds or thousands of CPUs, the processor plugin reaches its default timeout of 300 seconds when collecting huge content of the /sys/devices/system/cpu directory. As a workaround, increase the plugin’s timeout accordingly:

Running systemd within an older container image does not work

Running systemd within an older container image, for example, centos:7, does not work: