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Chapter 4. New features

This part describes new features and major enhancements introduced in Red Hat Enterprise Linux 8.5.

4.1. Installer and image creation

RHEL for Edge now supports a Simplified Installer

This enhancement enables Image Builder to build the RHEL for Edge Simplified Installer (edge-simplified-installer) and RHEL for Edge Raw Images (edge-raw-image).

RHEL for Edge Simplified Installer enables you to specify a new blueprint option, installation_device and thus, perform an unattended installation to a device. To create the raw image, you must provide an existing OSTree commit. It results in a raw image with the existing commit deployed in it. The installer will use this raw image to the specified installation device.

Additionally, you can also use Image Builder to build RHEL for Edge Raw Images. These are compressed raw images that contain a partition layout with an existing deployed OSTree commit in it. You can install the RHEL for Edge Raw Images to flash on a hard drive or booted in a virtual machine.

(BZ#1937854)

Warnings for deprecated kernel boot arguments

Anaconda boot arguments without the inst. prefix (for example, ks, stage2, repo and so on) are deprecated starting RHEL7. These arguments will be removed in the next major RHEL release.

With this release, appropriate warning messages are displayed when the boot arguments are used without the inst prefix. The warning messages are displayed in dracut when booting the installation and also when the installation program is started on a terminal.

Following is a sample warning message that is displayed on a terminal:

Deprecated boot argument ks must be used with the inst. prefix. Please use inst.ks instead. Anaconda boot arguments without inst. prefix have been deprecated and will be removed in a future major release.

Following is a sample warning message that is displayed in dracut:

ks has been deprecated. All usage of Anaconda boot arguments without the inst. prefix have been deprecated and will be removed in a future major release. Please use inst.ks instead.

(BZ#1897657)

Red Hat Connector is now fully supported

You can connect the system using Red Hat Connector (rhc). Red Hat Connector consists of a command-line interface and a daemon that allow users to execute Insights remediation playbook directly on their host within the web user interface of Insights (console.redhat.com). Red Hat Connector was available as a Technology Preview in RHEL 8.4 and as of RHEL 8.5, it is fully supported.

(BZ#1957316)

Ability to override official repositories available

By default, the osbuild-composer backend has its own set of official repositories defined in the /usr/share/osbuild-composer/repositories directory. Consequently, it does not inherit the system repositories located in the /etc/yum.repos.d/ directory. You can now override the official repositories. To do that, define overrides in the /etc/osbuild-composer/repositories and, as a result, the files located there take precedence over those in the /usr directory.

(BZ#1915351)

Image Builder now supports filesystem configuration

With this enhancement, you can specify custom filesystem configuration in your blueprints and you can create images with the desired disk layout. As a result, by having non-default layouts, you can benefit from security benchmarks, consistency with existing setups, performance, and protection against out-of-disk errors.

To customize the filesystem configuration in your blueprint, set the following customization: 

[[customizations.filesystem]]
mountpoint = "MOUNTPOINT"
size = MINIMUM-PARTITION-SIZE

(BZ#2011448)

Image Builder now supports creating bootable installer images

With this enhancement, you can use Image Builder to create bootable ISO images that consist of a tarball file, which contains a root file system. As a result, you can use the bootable ISO image to install the tarball file system to a bare metal system.

(BZ#2019318)

4.2. RHEL for Edge

Greenboot services now enabled by default

Previously, the greenboot services were not present in the default presets so, when the greenboot package was installed, users had to manually enable these greenboot services. With this update, the greenboot services are now present in the default presets configuration and users are no longer required to manually enable it.

(BZ#1935177)

4.3. Software management

RPM now has read-only support for the sqlite database backend

The ability to query an RPM database based on sqlite may be desired when inspecting other root directories, such as containers.This update adds read-only support for the RPM sqlite database backend. As a result, it is now possible to query packages installed in a UBI 9 or Fedora container from the host RHEL 8. To do that with Podman:

  1. Mount the container’s file system with the podman mount command.
  2. Run the rpm -qa command with the --root option pointing to the mounted location.

Note that RPM on RHEL 8 still uses the BerkeleyDB database (bdb) backend.

(BZ#1938928)

libmodulemd rebased to version 2.12.1

The libmodulemd packages have been rebased to version 2.12.1. Notable changes include:

  • Added support for version 1 of the modulemd-obsoletes document type, which provides information about a stream obsoleting another one, or a stream reaching its end of life.
  • Added support for version 3 of the modulemd-packager document type, which provides a packager description of a module stream content for a module build system.
  • Added support for the static_context attribute of the version 2 modulemd document type. With that, a module context is now defined by a packager instead of being generated by a module build system.
  • Now, a module stream value is always serialized as a quoted string.

(BZ#1894573)

libmodulemd rebased to version 2.13.0

The libmodulemd packages have been rebased to version 2.13.0, which provides the following notable changes over the previous version:

  • Added support for delisting demodularized packages from a module.
  • Added support for validating modulemd-packager-v3 documents with a new --type option of the modulemd-validator tool.
  • Fortified parsing integers.
  • Fixed various modulemd-validator issues.

(BZ#1984402)

sslverifystatus has been added to dnf configuration

With this update, when sslverifystatus option is enabled, dnf checks each server certificate revocation status using the Certificate Status Request TLS extension (OCSP stapling). As a result, when a revoked certificate is encountered, dnf refuses to download from its server.

(BZ#1814383)

4.4. Shells and command-line tools

ReaR has been updated to version 2.6

Relax-and-Recover (ReaR) has been updated to version 2.6. Notable bug fixes and enhancements include:

  • Added support for eMMC devices.
  • By default, all kernel modules are included in the rescue system. To include specific modules, set the MODULES array variable in the configuration file as: MODULES=( mod1 mod2 )
  • On the AMD and Intel 64-bit architectures and on IBM Power Systems, Little Endian, a new configuration variable GRUB2_INSTALL_DEVICES is introduced to control the location of the bootloader installation. See the description in /usr/share/rear/conf/default.conf for more details.
  • Improved backup of multipath devices.
  • Files under /media, /run, /mnt, /tmp are automatically excluded from backups as these directories are known to contain removable media or temporary files. See the description of the AUTOEXCLUDE_PATH variable in /usr/share/rear/conf/default.conf.
  • CLONE_ALL_USERS_GROUPS=true is now the default. See the description in /usr/share/rear/conf/default.conf for more details.

(BZ#1988493)

The modulemd-tools package is now available

With this update, the modulemd-tools package has been introduced which provides tools for parsing and generating modulemd YAML files.

To install modulemd-tools, use: 

# yum install modulemd-tools

(BZ#1924850)

opencryptoki rebased to version 3.16.0

opencryptoki has been upgraded to version 3.16.0. Notable bug fixes and enhancements include:

  • Improved the protected-key option and support for the attribute-bound keys in the EP11 core processor.
  • Improved the import and export of secure key objects in the cycle-count-accurate (CCA) processor.

(BZ#1919223)

lsvpd rebased to version 1.7.12

lsvpd has been upgraded to version 1.7.12. Notable bug fixes and enhancements include:

  • Added the UUID property in sysvpd.
  • Improved the NVMe firmware version.
  • Fixed PCI device manufacturer parsing logic.
  • Added recommends clause to the lsvpd configuration file.

(BZ#1844428)

ppc64-diag rebased to version 2.7.7

ppc64-diag has been upgraded to version 2.7.7. Notable bug fixes and enhancements include:

  • Improved unit test cases.
  • Added the UUID property in sysvpd.
  • The rtas_errd service does not run in the Linux containers.
  • The obsolete logging options are no longer available in the systemd service files.

(BZ#1779206)

The ipmi_power and ipmi_boot modules are available in the redhat.rhel_mgmt Collection

This update provides support to the Intelligent Platform Management Interface (IPMI) Ansible modules. IPMI is a specification for a set of management interfaces to communicate with baseboard management controller (BMC) devices. The IPMI modules - ipmi_power and ipmi_boot - are available in the redhat.rhel_mgmt Collection, which you can obtain by installing the ansible-collection-redhat-rhel_mgmt package.

(BZ#1843859)

udftools 2.3 are now added to RHEL

The udftools packages provide user-space utilities for manipulating Universal Disk Format (UDF) file systems. With this enhancement, udftools provides the following set of tools:

  • cdrwtool - It performs actions like blank, format, quick setup, and write to the DVD-R/CD-R/CD-RW media.
  • mkfs.udf, mkudffs - It creates a Universal Disk Format (UDF) filesystem.
  • pktsetup - It sets up and tears down the packet device.
  • udfinfo - It shows information about the Universal Disk Format (UDF) file system.
  • udflabel - It shows or changes the Universal Disk Format (UDF) file system label.
  • wrudf - It provides an interactive shell with cp, rm, mkdir, rmdir, ls, and cd operations on the existing Universal Disk Format (UDF) file system.

(BZ#1882531)

Tesseract 4.1.1 is now present in RHEL 8.5

Tesseract is an open-source OCR (optical character reading) engine and has the following features:

  • Starting with tesseract version 4, character recognition is based on Long Short-Term Memory (LSTM) neural networks.
  • Supports UTF-8.
  • Supports plain text, hOCR (HTML), PDF, and TSV output formats.

(BZ#1826085)

Errors when restoring LVM with thin pools do not happen anymore

With this enhancement, ReaR now detects when thin pools and other logical volume types with kernel metadata (for example, RAIDs and caches) are used in a volume group (VG) and switches to a mode where it recreates all the logical volumes (LVs) in the VG using lvcreate commands. Therefore, LVM with thin pools are restored without any errors.

Note

This new method does not preserve all the LV properties, for example LVM UUIDs. A restore from the backup should be tested before using ReaR in a Production environment in order to determine whether the recreated storage layout matches the requirements.

(BZ#1747468)

Net-SNMP now detects RSA and ECC certificates

Previously, Net-Simple Network Management Protocol (Net-SNMP) detected only Rivest, Shamir, Adleman (RSA) certificates. This enhancement adds support for Elliptic Curve Cryptography (ECC). As a result, Net-SNMP now detects RSA and ECC certificates.

(BZ#1919714)

FCoE option is changed to rd.fcoe

Previously, the man page for dracut.cmdline documented rd.nofcoe=0 as the command to turn off Fibre Channel over Ethernet (FCoE).

With this update, the command is changed to rd.fcoe. To disable FCoE, run the command rd.fcoe=0.

For further information on FCoE see, Configuring Fibre Channel over Ethernet

(BZ#1929201)

4.5. Infrastructure services

linuxptp rebased to version 3.1

The linuxptp package has been updated to version 3.1. Notable bug fixes and enhancements include:

  • Added ts2phc program for synchronization of Precision Time Protocol (PTP) hardware clock to Pulse Per Second (PPS) signal.
  • Added support for the automotive profile.
  • Added support for client event monitoring.

(BZ#1895005)

chrony rebased to version 4.1

chrony has been updated to version 4.1. Notable bug fixes and enhancements include:

  • Added support for Network Time Security (NTS) authentication. For more information, see Overview of Network Time Security (NTS) in chrony.
  • By default, the Authenticated Network Time Protocol (NTP) sources are trusted over non-authenticated NTP sources. Add the autselectmode ignore argument in the chrony.conf file to restore the original behavior.
  • The support for authentication with RIPEMD keys - RMD128, RMD160, RMD256, RMD320 is no longer available.
  • The support for long non-standard MACs in NTPv4 packets is no longer available. If you are using chrony 2.x, non-MD5/SHA1 keys, you need to configure chrony with the version 3 option.

(BZ#1895003)

PowerTop rebased to version 2.14

PowerTop has been upgraded to version 2.14. This is an update adding Alder Lake, Sapphire Rapids, and Rocket Lake platforms support.

(BZ#1834722)

TuneD now moves unnecessary IRQs to housekeeping CPUs

Network device drivers like i40e, iavf, mlx5, evaluate the online CPUs to determine the number of queues and hence the MSIX vectors to be created.

In low-latency environments with a large number of isolated and very few housekeeping CPUs, when TuneD tries to move these device IRQs to the housekeeping CPUs it fails due to the per CPU vector limit.

With this enhancement, TuneD explicitly adjusts the numbers of network device channels (and hence MSIX vectors) as per the housekeeping CPUs. Therefore, all the device IRQs can now be moved on the housekeeping CPUs to achieve low latency.

(BZ#1951992)

4.6. Security

libreswan rebased to 4.4

The libreswan packages have been upgraded to upstream version 4.4, which introduces many enhancements and bug fixes. Most notably:

  • The IKEv2 protocol:

    • Introduced fixes for TCP encapsulation in Transport Mode and host-to-host connections.
    • Added the --globalstatus option to the ipsec whack command for displaying redirect statistics.
    • The vhost and vnet values in the ipsec.conf configuration file are no longer allowed for IKEv2 connections.

  • The pluto IKE daemon:

    • Introduced fixes for host-to-host connections that use non-standard IKE ports.
    • Added peer ID (IKEv2 IDr or IKEv1 Aggr) to select the best initial connection.
    • Disabled the interface-ip= option because Libreswan does not provide the corresponding functionality yet.
    • Fixed the PLUTO_PEER_CLIENT variable in the ipsec__updown script for NAT in Transport Mode.
    • Set the PLUTO_CONNECTION_TYPE variable to transport or tunnel.
    • Non-templated wildcard ID connections can now match.

(BZ#1958968)

GnuTLS rebased to 3.6.16

The gnutls packages have been updated to version 3.6.16. Notable bug fixes and enhancements include:

  • The gnutls_x509_crt_export2() function now returns 0 instead of the size of the internal base64 blob in case of success. This aligns with the documentation in the gnutls_x509_crt_export2(3) man page.
  • Certificate verification failures due to the Online Certificate Status Protocol (OCSP) must-stapling not being followed are now correctly marked with the GNUTLS_CERT_INVALID flag.
  • Previously, even when TLS 1.2 was explicitly disabled through the -VERS-TLS1.2 option, the server still offered TLS 1.2 if TLS 1.3 was enabled. The version negotiation has been fixed, and TLS 1.2 can now be correctly disabled.

(BZ#1956783)

socat rebased to 1.7.4

The socat packages have been upgraded from version 1.7.3 to 1.7.4, which provides many bug fixes and improvements. Most notably:

  • GOPEN and UNIX-CLIENT addresses now support SEQPACKET sockets.
  • The generic setsockopt-int and related options are, in the case of listening or accepting addresses, applied to the connected sockets. To enable setting options on a listening socket, the setsockopt-listen option is now available.
  • Added the -r and -R options for a raw dump of transferred data to a file.
  • Added the ip-transparent option and the IP_TRANSPARENT socket option.
  • OPENSSL-CONNECT now automatically uses the SNI feature and the openssl-no-sni option turns SNI off. The openssl-snihost option overrides the value of the openssl-commonname option or the server name.
  • Added the accept-timeout and listen-timeout options.
  • Added the ip-add-source-membership option.
  • UDP-DATAGRAM address now does not check peer port of replies as it did in 1.7.3. Use the sourceport optioon if your scenario requires the previous behavior.
  • New proxy-authorization-file option reads PROXY-CONNECT credentials from a file and enables to hide this data from the process table.
  • Added AF_VSOCK support for VSOCK-CONNECT and VSOCK-LISTEN addresses.

(BZ#1947338)

crypto-policies rebased to 20210617

The crypto-policies packages have been upgraded to upstream version 20210617, which provides a number of enhancements and bug fixes over the previous version, most notably:

  • You can now use scoped policies to enable different sets of algorithms for different back ends. Each configuration directive can now be limited to specific protocols, libraries, or services. For a complete list of available scopes and details on the new syntax, see the crypto-policies(7) man page. For example, the following directive allows using AES-256-CBC cipher with the SSH protocol, impacting both the libssh library and the OpenSSH suite: 

    cipher@SSH = AES-256-CBC+

  • Directives can now use asterisks for specifying multiple values using wildcards. For example, the following directive disables all CBC mode ciphers for applications using libssh: 

    cipher@libssh = -*-CBC

    Note that future updates can introduce new algorithms matched by the current wildcards.

(BZ#1960266)

crypto-policies now support AES-192 ciphers in custom policies

The system-wide cryptographic policies now support the following values for the cipher option in custom policies and subpolicies: AES-192-GCM, AES-192-CCM, AES-192-CTR, and AES-192-CBC. As a result, you can enable the AES-192-GCM and AES-192-CBC ciphers for the Libreswan application and the AES-192-CTR and AES-192-CBC ciphers for the libssh library and the OpenSSH suite through crypto-policies.

(BZ#1876846)

CBC ciphers disabled in the FUTURE cryptographic policy

This update of the crypto-policies packages disables ciphers that use cipher block chaining (CBC) mode in the FUTURE policy. The settings in FUTURE should withstand near-term future attacks, and this change reflects the current progress. As a result, system components respecting crypto-policies cannot use CBC mode when the FUTURE policy is active.

(BZ#1933016)

Adding new kernel AVC tracepoint

With this enhancement, a new avc:selinux_audited kernel tracepoint is added that triggers when an SELinux denial is to be audited. This feature allows for more convenient low-level debugging of SELinux denials. The new tracepoint is available for tools such as perf.

(BZ#1954024)

New ACSC ISM profile in the SCAP Security Guide

The scap-security-guide packages now provide the Australian Cyber Security Centre (ACSC) Information Security Manual (ISM) compliance profile and a corresponding Kickstart file. With this enhancement, you can install a system that conforms with this security baseline and use the OpenSCAP suite for checking security compliance and remediation using the risk-based approach for security controls defined by ACSC.

(BZ#1955373)

SCAP Security Guide rebased to 0.1.57

The scap-security-guide packages have been rebased to upstream version 0.1.57, which provides several bug fixes and improvements. Most notably:

  • The Australian Cyber Security Centre (ACSC) Information Security Manual (ISM) profile has been introduced. The profile extends the Essential Eight profile and adds more security controls defined in the ISM.
  • The Center for Internet Security (CIS) profile has been restructured into four different profiles respecting levels of hardening and system type (server and workstation) as defined in the official CIS benchmarks.
  • The Security Technical Implementation Guide (STIG) security profile has been updated, and implements rules from the recently-released version V1R3.
  • The Security Technical Implementation Guide with GUI (STIG with GUI) security profile has been introduced. The profile derives from the STIG profile and is compatible with RHEL installations that select the Server with GUI package selection.
  • The ANSSI High level profile, which is based on the ANSSI BP-028 recommendations from the French National Security Agency (ANSSI), has been introduced. This contains a profile implementing rules of High hardening levels.

(BZ#1966577)

OpenSCAP rebased to 1.3.5

The OpenSCAP packages have been rebased to upstream version 1.3.5. Notable fixes and enhancements include:

  • Enabled Schematron-based validation by default for the validate command of oval and xccdf modules.
  • Added SCAP 1.3 source data stream Schematron.
  • Added XML signature validation.
  • Allowed clamping mtime to SOURCE_DATE_EPOCH.
  • Added severity and role attributes.
  • Support for requires and conflicts elements of the Rule and Group (XCCDF).
  • Kubernetes remediation in the HTML report.
  • Handling gpfs, proc and sysfs file systems as non-local.
  • Fixed handling of common options styled as --arg=val.
  • Fixed behavior of the StateType operator.
  • Namespace ignored in XPath expressions (xmlfilecontent) to allow for incomplete XPath queries.
  • Fixed a problem that led to a warning about the presence of obtrusive data.
  • Fixed multiple segfaults and a broken test in the --stig-viewer feature.
  • Fixed the TestResult/benchmark/@href attribute.
  • Fixed many memory management issues.
  • Fixed many memory leaks.

(BZ#1953092)

Validation of digitally signed SCAP source data streams

To conform with the Security Content Automation Protocol (SCAP) 1.3 specifications, OpenSCAP now validates digital signatures of digitally signed SCAP source data streams. As a result, OpenSCAP validates the digital signature when evaluating a digitally signed SCAP source data stream. The signature validation is performed automatically while loading the file. Data streams with invalid signatures are rejected, and OpenSCAP does not evaluate their content. OpenSCAP uses the XML Security Library with the OpenSSL cryptography library to validate the digital signature.

You can skip the signature validation by adding the --skip-signature-validation option to the oscap xccdf eval command.

Important

OpenSCAP does not address the trustworthiness of certificates or public keys that are part of the KeyInfo signature element and that are used to verify the signature. You should verify such keys by yourselves to prevent evaluation of data streams that have been modified and signed by bad actors.

(BZ#1966612)

New DISA STIG profile compatible with Server with GUI installations

A new profile, DISA STIG with GUI, has been added to the SCAP Security Guide. This profile is derived from the DISA STIG profile and is compatible with RHEL installations that selected the Server with GUI package group. The previously existing stig profile was not compatible with Server with GUI because DISA STIG demands uninstalling any Graphical User Interface. However, this can be overridden if properly documented by a Security Officer during evaluation. As a result, the new profile helps when installing a RHEL system as a Server with GUI aligned with the DISA STIG profile.

(BZ#1970137)

STIG security profile updated to version V1R3

The DISA STIG for Red Hat Enterprise Linux 8 profile in the SCAP Security Guide has been updated to align with the latest version V1R3. The profile is now also more stable and better aligns with the RHEL 8 STIG (Security Technical Implementation Guide) manual benchmark provided by the Defense Information Systems Agency (DISA).

This second iteration brings approximately 90% of coverage with regards to the STIG. You should use only the current version of this profile because older versions are no longer valid.

Warning

Automatic remediation might render the system non-functional. Run the remediation in a test environment first.

(BZ#1993056)

Three new CIS profiles in SCAP Security Guide

Three new compliance profiles aligned with the Center for Internet Security (CIS) Red Hat Enterprise Linux 8 Benchmark have been introduced to the SCAP Security Guide. The CIS RHEL 8 Benchmark provides different configuration recommendations for "Server" and "Workstation" deployments, and defines two levels of configuration, "level 1" and "level 2" for each deployment. The CIS profile previously shipped in RHEL8 represented only the "Server Level 2". The three new profiles complete the scope of the CIS RHEL8 Benchmark profiles, and you can now more easily evaluate your system against CIS recommendations.

All currently available CIS RHEL 8 profiles are:

Workstation Level 1

xccdf_org.ssgproject.content_profile_cis_workstation_l1

Workstation Level 2

xccdf_org.ssgproject.content_profile_cis_workstation_l2

Server Level 1

xccdf_org.ssgproject.content_profile_cis_server_l1

Server Level 2

xccdf_org.ssgproject.content_profile_cis

(BZ#1993197)

Performance of remediations for Audit improved by grouping similar system calls

Previously, Audit remediations generated an individual rule for each system call audited by the profile. This led to large numbers of audit rules, which degraded performance. With this enhancement, remediations for Audit can group rules for similar system calls with identical fields together into a single rule, which improves performance.

Examples of system calls grouped together: 

-a always, exit -F arch=b32 -S chown, fchown, fchownat, lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
-a always, exit -F arch=b32 -S unlink, unlinkat, rename, renameat, rmdir -F auid>=1000 -F auid!=unset -F key=delete
-a always, exit -F arch=b32 -S chown, fchown, fchownat, lchown -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccesful-perm-change
-a always, exit -F arch=b32 -S unlink, unlinkat, rename, renameat -F auid>=1000 -F auid!=unset -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=unsuccessful-delete

(BZ#1876483)

Added profile for ANSSI-BP-028 High level

The ANSSI High level profile, based on the ANSSI BP-028 recommendations from the French National Security Agency (ANSSI), has been introduced. This completes the availability of profiles for all ANSSI-BP-028 v1.2 hardening levels in the SCAP Security Guide. With the new profile, you can harden the system to the recommendations from ANSSI for GNU/Linux Systems at the High hardening level. As a result, you can configure and automate compliance of your RHEL 8 systems to the strictest hardening level by using the ANSSI Ansible Playbooks and the ANSSI SCAP profiles.

(BZ#1955183)

OpenSSL added for encrypting Rsyslog TCP and RELP traffic

The OpenSSL network stream driver has been added to Rsyslog. This driver implements TLS-protected transport using the OpenSSL library. This provides additional functionality compared to the stream driver using the GnuTLS library. As a result, you can now use either OpenSSL or GnuTLS as an Rsyslog network stream driver.

(BZ#1891458)

Rsyslog rebased to 8.2102.0-5

The rsyslog packages have been rebased to upstream version 8.2102.0-5, which provides the following notable changes over the previous version:

  • Added the exists() script function to check whether a variable exists or not, for example $!path!var.
  • Added support for setting OpenSSL configuration commands with a new configuration parameter tls.tlscfgcmd for the omrelp and imrelp modules.

  • Added new rate-limit options to the omfwd module for rate-limiting syslog messages sent to the remote server:

    • ratelimit.interval specifies the rate-limiting interval in seconds.
    • ratelimit.burst specifies the rate-limiting burst in the number of messages.
  • Rewritten the immark module with various improvements.
  • Added the max sessions config parameter to the imptcp module. The maximum is measured per instance, not globally across all instances.
  • Added the rsyslog-openssl subpackage; this network stream driver implements TLS-protected transport using the OpenSSL library.
  • Added per-minute rate limiting to the imfile module with the MaxBytesPerMinute and MaxLinesPerMinute options. These options accept integer values and limit the number of bytes or lines that may be sent in a minute.
  • Added support to the imtcp and omfwd module to configure a maximum depth for the certificate chain verification with the streamdriver.TlsVerifyDepth option.

(BZ#1932795)

4.7. Networking

Support for pause parameter of ethtool in NetworkManager

Non auto-pause parameters need to be set explicitly on a specific network interface in certain cases. Previously, NetworkManager could not pause the control flow parameters of ethtool in nmstate. To disable the auto negotiation of the pause parameter and enable RX/TX pause support explicitly, use the following command: 

# nmcli connection modify enp1s0 ethtool.pause-autoneg no ethtool.pause-rx true ethtool.pause-tx true

(BZ#1899372)

New property in NetworkManager for setting physical and virtual interfaces in promiscuous mode

With this update the 802-3-ethernet.accept-all-mac-addresses property has been added to NetworkManager for setting physical and virtual interfaces in the accept all MAC addresses mode. With this update, the kernel can accept network packages targeting current interfaces’ MAC address in the accept all MAC addresses mode. To enable accept all MAC addresses mode on eth1, use the following command: 

$ sudo nmcli c add type ethernet  ifname eth1 connection.id eth1  802-3-ethernet.accept-all-mac-addresses true

(BZ#1942331)

NetworkManager rebased to version 1.32.10

The NetworkManager packages have been upgraded to upstream version 1.32.10, which provides a number of enhancements and bug fixes over the previous version.

For further information about notable changes, read the upstream release notes for this version.

(BZ#1934465)

NetworkManager now supports nftables as firewall back end

This enhancement adds support for the nftables firewall framework to NetworkManager. To switch the default back end from iptables to nftables:

  1. Create the /etc/NetworkManager/conf.d/99-firewall-backend.conf file with the following content: 

    [main]
firewall-backend=nftables

  2. Reload the NetworkManager service. 

    # systemctl reload NetworkManager

(BZ#1548825)

firewalld rebased to version 0.9.3

The firewalld packages have been upgraded to upstream version 0.9.3, which provides a number of enhancements and bug fixes over the previous version.

For further details, see the upstream release notes:

(BZ#1872702)

The firewalld policy objects feature is now available

Previously, you could not use firewalld to filter traffic flowing between virtual machines, containers, and zones. With this update, the firewalld policy objects feature has been introduced, which provides forward and output filtering in firewalld.

(BZ#1492722)

Multipath TCP is now fully supported

Starting with RHEL 8.5, Multipath TCP (MPTCP) is fully supported. MPTCP improves resource usage within the network and resilience to network failure. For example, with Multipath TCP on the RHEL server, smartphones with MPTCP v1 enabled can connect to an application running on the server and switch between Wi-Fi and cellular networks without interrupting the connection to the server.

RHEL 8.5 introduced additional features, such as:

  • Multiple concurrent active substreams
  • Active-backup support
  • Improved stream performances
  • Better memory usage, with receive and send buffer auto-tuning
  • SYN cookie support

Note that either the applications running on the server must natively support MPTCP or administrators must load an eBPF program into the kernel to dynamically change IPPROTO_TCP to IPPROTO_MPTCP.

For further details see, Getting started with Multipath TCP.

(JIRA:RHELPLAN-57712)

Alternative network interface naming is now available in RHEL

Alternative interface naming is the RHEL kernel configuration, which provides the following networking benefits:

  • Network interface card (NIC) names can have arbitrary length.
  • One NIC can have multiple names at the same time.
  • Usage of alternative names as handles for commands.

(BZ#2164986)

4.8. Kernel

Kernel version in RHEL 8.5

Red Hat Enterprise Linux 8.5 is distributed with the kernel version 4.18.0-348.

(BZ#1839151)

EDAC for Intel Sapphire Rapids processors is now supported

This enhancement provides Error Detection And Correction (EDAC) device support for Intel Sapphire Rapids processors. EDAC mainly handles Error Code Correction (ECC) memory and detects and reports PCI bus parity errors.

(BZ#1837389)

The bpftrace package rebased to version 0.12.1

The bpftrace package has been upgraded to version 0.12.1, which provides multiple bug fixes and enhancements. Notable changes over previous versions include:

  • Added the new builtin path, which is a new reliable method to display the full path from a path structure.
  • Added wildcard support for kfunc probes and tracepoint categories.

(BZ#1944716)

vmcore capture works as expected after CPU hot-add or hot-removal operations

Previously, on IBM POWER systems, after every CPU or memory hot-plug or removal operation, the CPU data on the device tree became stale unless the kdump.service is reloaded. To reload the latest CPU information, the kdump.service parses through the device nodes to fetch the CPU information. However, some of the CPU nodes are already lost during its hot-removal. Consequently, a race condition between the kdump.service reload and a CPU hot-removal happens at the same time and this may cause the dump to fail. A subsequent crash might then not capture the vmcore file.

This update eliminates the need to reload the kdump.service after a CPU hot-plug and the vmcore capture works as expected in the described scenario.

Note: This enhancement works as expected for firmware-assisted dumps (fadump). In the case of standard kdump, the kdump.service reload takes place during the hot-plug operation.

(BZ#1922951)

The kdumpctl command now supports the new kdumpctl estimate utility

The kdumpctl command now supports the kdumpctl estimate utility. Based on the existing kdump configuration, kdumpctl estimate prints a suitable estimated value for kdump memory allocation.

The minimum size of the crash kernel may vary depending on the hardware and machine specifications. Hence, previously, it was difficult to estimate an accurate crashkernel= value.

With this update, the kdumpctl estimate utility provides an estimated value. This value is a best effort recommended estimate and can serve as a good reference to configure a feasible crashkernel= value.

(BZ#1879558)

IBM TSS 2.0 package rebased to 1.6.0

The IBM’s Trusted Computing Group (TCG) Software Stack (TSS) 2.0 binary package has been upgraded to 1.6.0. This update adds the IBM TSS 2.0 support on AMD64 and Intel 64 architecture.

It is a user space TSS for Trusted Platform Modules (TPM) 2.0 and implements the functionality equivalent to (but not API compatible with) the TCG TSS working group’s Enhanced System Application Interface (ESAPI), System Application Interface (SAPI), and TPM Command Transmission Interface (TCTI) API with a simpler interface.

It is a security middleware that allows applications and platforms to share and integrate the TPM into secure applications.

This rebase provides many bug fixes and enhancements over the previous version. The most notable changes include the following new attributes:

  • tsscertifyx509: validates the x509 certificate
  • tssgetcryptolibrary: displays the current cryptographic library
  • tssprintattr: prints the TPM attributes as text
  • tsspublicname: calculates the public name of an entity
  • tsssetcommandcodeauditstatus: clears or sets code via TPM2_SetCommandCodeAuditStatus
  • tsstpmcmd: sends an in-band TPM simulator signal

(BZ#1822073)

The schedutil CPU frequency governor is now available on RHEL 8

The schedutil CPU governor uses CPU utilization data available on the CPU scheduler. schedutil is a part of the CPU scheduler and it can access the scheduler’s internal data structures directly. schedutil controls how the CPU would raise and lower its frequency in response to system load. You must manually select the schedutil frequency governor as it is not enabled as default.

There is one policyX directory per CPU. schedutil is available in the policyX/scaling_governors list of the existing CPUFreq governors in the kernel and is attached to /sys/devices/system/cpu/cpufreq/policyx policy. The policy file can be overwritten to change it.

Note that when using intel_pstate scaling drivers, it might be necessary to configure the intel_pstate=passive command line argument for intel_pstate to become available and be listed by the governor. intel_pstate is the default on Intel hardware with any modern CPU.

(BZ#1938339)

The rt-tests suite rebased to rt-tests-2.1 upstream version

The rt-tests suite has been rebased to rt-tests-2.1 version, which provides multiple bug fixes and enhancements. The notable changes over the previous version include:

  • Fixes to various programs in the rt-tests suite.
  • Fixes to make programs more uniform with the common set of options, for example, the oslat program’s option -t --runtime option is renamed to -D to specify the run duration to match the rest of the suite.
  • Implements a new feature to output data in json format.

(BZ#1954387)

Intel® QuickAssist Technology Library (QATlib) was rebased to version 21.05

The qatlib package has been rebased to version 21.05, which provides multiple bug fixes and enhancements. Notable changes include:

  • Adding support for several encryption algorithms:

    • AES-CCM 192/256
    • ChaCha20-Poly1305
    • PKE 8K (RSA, DH, ModExp, ModInv)
  • Fixing device enumeration on different nodes
  • Fixing pci_vfio_set_command for 32-bit builds

For more information about QATlib installation, check Ensuring that Intel® QuickAssist Technology stack is working correctly on RHEL 8.

(BZ#1920237)

4.9. File systems and storage

xfs_quota state command now outputs all grace times when multiple quota types are specified

The xfs_quota state command now outputs grace times for multiple quota types specified on the command line. Previously, only one was shown even if more than one of -g, -p, or -u was specified.

(BZ#1949743)

-H option added to the rpc.gssd daemon and the set-home option added to the /etc/nfs.conf file

This patch adds the -H option to rpc.gssd and the set-home option into /etc/nfs.conf, but does not change the default behavior.

By default, rpc.gssd sets $HOME to / to avoid possible deadlock that may happen when users' home directories are on an NFS share with Kerberos security. If either the -H option is added to rpc.gssd, or set-home=0 is added to /etc/nfs.conf, rpc.gssd does not set $HOME to /.

These options allow you to use Kerberos k5identity files in $HOME/.k5identity and assumes NFS home directory is not on an NFS share with Kerberos security. These options are provided for use in only specific environments, such as the need for k5identity files. For more information see the k5identity man page.

(BZ#1868087)

The storage RHEL system role now supports LVM VDO volumes

Virtual Data Optimizer (VDO) helps to optimize usage of the storage volumes. With this enhancement, administrators can use the storage system role to manage compression and deduplication on Logical Manager Volumes (LVM) VDO volumes.

(BZ#1882475)

4.10. High availability and clusters

Local mode version of pcs cluster setup command is now fully supported

By default, the pcs cluster setup command automatically synchronizes all configuration files to the cluster nodes. Since RHEL 8.3, the pcs cluster setup command has provided the --corosync-conf option as a Technology Preview. This feature is now fully supported in RHEL 8.5. Specifying this option switches the command to local mode. In this mode, the pcs command-line interface creates a corosync.conf file and saves it to a specified file on the local node only, without communicating with any other node. This allows you to create a corosync.conf file in a script and handle that file by means of the script.

(BZ#1839637)

Ability to configure watchdog-only SBD for fencing on subset of cluster nodes

Previously, to use a watchdog-only SBD configuration, all nodes in the cluster had to use SBD. That prevented using SBD in a cluster where some nodes support it but other nodes (often remote nodes) required some other form of fencing. Users can now configure a watchdog-only SBD setup using the new fence_watchdog agent, which allows cluster configurations where only some nodes use watchdog-only SBD for fencing and other nodes use other fencing types. A cluster may only have a single such device, and it must be named watchdog.

(BZ#1443666)

New pcs command to update SCSI fencing device without causing restart of all other resources

Updating a SCSI fencing device with the pcs stonith update command causes a restart of all resources running on the same node where the stonith resource was running. The new pcs stonith update-scsi-devices command allows you to update SCSI devices without causing a restart of other cluster resources.

(BZ#1872378)

New reduced output display option for pcs resource safe-disable command

The pcs resource safe-disable and pcs resource disable --safe commands print a lengthy simulation result after an error report. You can now specify the --brief option for those commands to print errors only. The error report now always contains resource IDs of affected resources.

(BZ#1909901)

pcs now accepts Promoted and Unpromoted as role names

The pcs command-line interface now accepts Promoted and Unpromoted anywhere roles are specified in Pacemaker configuration. These role names are the functional equivalent of the Master and Slave Pacemaker roles. Master and Slave remain the names for these roles in configuration displays and help text.

(BZ#1885293)

New pcs resource status display commands

The pcs resource status and the pcs stonith status commands now support the following options:

  • You can display the status of resources configured on a specific node with the pcs resource status node=node_id command and the pcs stonith status node=node_id command. You can use these commands to display the status of resources on both cluster and remote nodes.
  • You can display the status of a single resource with the pcs resource status resource_id and the pcs stonith status resource_id commands.
  • You can display the status of all resources with a specified tag with the pcs resource status tag_id and the pcs stonith status tag_id commands.

(BZ#1290830, BZ#1285269)

New LVM volume group flag to control autoactivation

LVM volume groups now support a setautoactivation flag which controls whether logical volumes that you create from a volume group will be automatically activated on startup. When creating a volume group that will be managed by Pacemaker in a cluster, set this flag to n with the vgcreate --setautoactivation n command for the volume group to prevent possible data corruption. If you have an existing volume group used in a Pacemaker cluster, set the flag with vgchange --setautoactivation n.

(BZ#1899214)

4.11. Dynamic programming languages, web and database servers

The nodejs:16 module stream is now fully supported

The nodejs:16 module stream, previously available as a Technology preview, is fully supported with the release of the RHSA-2021:5171 advisory. The nodejs:16 module stream now provides Node.js 16.13.1, which is a Long Term Support (LTS) version.

Node.js 16 included in RHEL 8.5 provides numerous new features and bug and security fixes over Node.js 14 available since RHEL 8.3.

Notable changes include:

  • The V8 engine has been upgraded to version 9.4.
  • The npm package manager has been upgraded to version 8.1.2.
  • A new Timers Promises API provides an alternative set of timer functions that return Promise objects.
  • Node.js now provides a new experimental Web Streams API.
  • Node.js now includes Corepack, an experimental tool that enables you to use package managers configured in the given project without the need to manually install them.
  • Node.js now provides an experimental ECMAScript modules (ESM) loader hooks API, which consolidates ESM loader hooks.

To install the nodejs:16 module stream, use: 

# yum module install nodejs:16

If you want to upgrade from the nodejs:14 stream, see Switching to a later stream.

(BZ#1953991, BZ#2027610)

A new module stream: ruby:3.0

RHEL 8.5 introduces Ruby 3.0.2 in a new ruby:3.0 module stream. This version provides a number of performance improvements, bug and security fixes, and new features over Ruby 2.7 distributed with RHEL 8.3.

Notable enhancements include:

  • Concurrency and parallelism features:

    • Ractor, an Actor-model abstraction that provides thread-safe parallel execution, is provided as an experimental feature.
    • Fiber Scheduler has been introduced as an experimental feature. Fiber Scheduler intercepts blocking operations, which enables light-weight concurrency without changing existing code.

  • Static analysis features:

    • The RBS language has been introduced, which describes the structure of Ruby programs. The rbs gem has been added to parse type definitions written in RBS.
    • The TypeProf utility has been introduced, which is a type analysis tool for Ruby code.
  • Pattern matching with the case/in expression is no longer experimental.
  • One-line pattern matching, which is an experimental feature, has been redesigned.
  • Find pattern has been added as an experimental feature.

The following performance improvements have been implemented:

  • Pasting long code to the Interactive Ruby Shell (IRB) is now significantly faster.
  • The measure command has been added to IRB for time measurement.

Other notable changes include:

  • Keyword arguments have been separated from other arguments.
  • The default directory for user-installed gems is now $HOME/.local/share/gem/ unless the $HOME/.gem/ directory is already present.

To install the ruby:3.0 module stream, use: 

# yum module install ruby:3.0

If you want to upgrade from an earlier ruby module stream, see Switching to a later stream.

(BZ#1938942)

Changes in the default separator for the Python urllib parsing functions

To mitigate the Web Cache Poisoning CVE-2021-23336 in the Python urllib library, the default separator for the urllib.parse.parse_qsl and urllib.parse.parse_qs functions is being changed from both ampersand (&) and semicolon (;) to only an ampersand.

This change was implemented in Python 3.6 with the release of RHEL 8.4, and now is being backported to Python 3.8 and Python 2.7.

The change of the default separator is potentially backwards incompatible, therefore Red Hat provides a way to configure the behavior in Python packages where the default separator has been changed. In addition, the affected urllib parsing functions issue a warning if they detect that a customer’s application has been affected by the change.

For more information, see the Mitigation of Web Cache Poisoning in the Python urllib library (CVE-2021-23336) Knowledgebase article.

Python 3.9 is unaffected and already includes the new default separator (&), which can be changed only by passing the separator parameter when calling the urllib.parse.parse_qsl and urllib.parse.parse_qs functions in Python code.

(BZ#1935686, BZ#1931555, BZ#1969517)

The Python ipaddress module no longer allows zeros in IPv4 addresses

To mitigate CVE-2021-29921, the Python ipaddress module now rejects IPv4 addresses with leading zeros with an AddressValueError: Leading zeros are not permitted error.

This change has been introduced in the python38 and python39 modules. Earlier Python versions distributed in RHEL are not affected by CVE-2021-29921.

Customers who rely on the previous behavior can pre-process their IPv4 address inputs to strip the leading zeros off. For example: 

>>> def reformat_ip(address): return '.'.join(part.lstrip('0') if part != '0' else part for part in address.split('.'))
>>> reformat_ip('0127.0.0.1')
'127.0.0.1'

To strip the leading zeros off with an explicit loop for readability, use: 

def reformat_ip(address):
    parts = []
    for part in address.split('.'):
        if part != "0":
            part = part.lstrip('0')
        parts.append(part)
    return '.'.join(parts)

(BZ#1986007, BZ#1970504, BZ#1970505)

The php:7.4 module stream rebased to version 7.4.19

The PHP scripting language, provided by the php:7.4 module stream, has been upgraded from version 7.4.6 to version 7.4.19. This update provides multiple security and bug fixes.

(BZ#1944110)

A new package: pg_repack

A new pg_repack package has been added to the postgresql:12 and postgresql:13 module streams. The pg_repack package provides a PostgreSQL extension that lets you remove bloat from tables and indexes, and optionally restore physical order of clustered indexes.

(BZ#1967193, BZ#1935889)

A new module stream: nginx:1.20

The nginx 1.20 web and proxy server is now available as the nginx:1.20 module stream. This update provides a number of bug fixes, security fixes, new features, and enhancements over the previously released version 1.18.

New features:

  • nginx now supports client SSL certificate validation with Online Certificate Status Protocol (OCSP).
  • nginx now supports cache clearing based on the minimum amount of free space. This support is implemented as the min_free parameter of the proxy_cache_path directive.
  • A new ngx_stream_set_module module has been added, which enables you to set a value for a variable.

Enhanced directives:

  • Multiple new directives are now available, such as ssl_conf_command and ssl_reject_handshake.
  • The proxy_cookie_flags directive now supports variables.

Improved support for HTTP/2:

  • The ngx_http_v2 module now includes the lingering_close, lingering_time, lingering_timeout directives.
  • Handling connections in HTTP/2 has been aligned with HTTP/1.x. From nginx 1.20, use the keepalive_timeout and keepalive_requests directives instead of the removed http2_recv_timeout, http2_idle_timeout, and http2_max_requests directives.

To install the nginx:1.20 stream, use: 

# yum module install nginx:1.20

If you want to upgrade from the nginx:1.20 stream, see Switching to a later stream.

(BZ#1945671)

The squid:4 module stream rebased to version 4.15

The Squid proxy server, available in the squid:4 module stream, has been upgraded from version 4.11 to version 4.15. This update provides various bug and security fixes.

(BZ#1964384)

LVM system.devices file feature now available in RHEL 8

RHEL 8.5 introduces the LVM system.devices file feature. By creating a list of devices in the /etc/lvm/devices/system.devices file, you can select specific devices for LVM to recognize and use, and prevent LVM from using unwanted devices.

To enable the system.devices file feature, set use_devicesfile=1 in the lvm.conf configuration file and add devices to the system.devices file. LVM ignores any devices filter settings while the system.devices file feature is enabled. To prevent warning messages, remove your filter settings from the lvm.conf file.

For more information, see the lvmdevices(8) man page.

(BZ#1922312)

quota now supports HPE XFS

The quota utilities now provide support for the HPE XFS file system. As a result, users of HPE XFS can monitor and and manage user and group disk usage through quota utilities.

(BZ#1945408)

mutt rebased to version 2.0.7

The Mutt email client has been updated to version 2.0.7, which provides a number of enhancements and bug fixes.

Notable changes include:

  • Mutt now provides support for the OAuth 2.0 authorization protocol using the XOAUTH2 mechanism. Mutt now also supports the OAUTHBEARER authentication mechanism for the IMAP, POP, and SMTP protocols. The OAuth-based functionality is provided through external scripts. As a result, you can connect Mutt with various cloud email providers, such as Gmail using authentication tokens. For more information on how to set up Mutt with OAuth support, see How to set up Mutt with Gmail using OAuth2 authentication.
  • Mutt adds support for domain-literal email addresses, for example, user@[IPv6:fcXX:…​].
  • The new $ssl_use_tlsv1_3 configuration variable allows TLS 1.3 connections if they are supported by the email server. This variable is enabled by default.
  • The new $imap_deflate variable adds support for the COMPRESS=DEFLATE compression. The variable is disabled by default.
  • The $ssl_starttls variable no longer controls aborting an unencrypted IMAP PREAUTH connection. Use the $ssl_force_tls variable instead if you rely on the STARTTLS process.

Note that even after an update to the new Mutt version, the ssl_force_tls configuration variable still defaults to no to prevent RHEL users from encountering problems in their existing environments. In the upstream version of Mutt, ssl_force_tls is now enabled by default.

(BZ#1912614, BZ#1890084)

4.12. Compilers and development tools

Go Toolset rebased to version 1.16.7

Go Toolset has been upgraded to version 1.16.7. Notable changes include:

  • The GO111MODULE environment variable is now set to on by default. To revert this setting, change GO111MODULE to auto.
  • The Go linker now uses less resources and improves code robustness and maintainability. This applies to all supported architectures and operating systems.
  • With the new embed package you can access embedded files while compiling programs.
  • All functions of the io/ioutil package have been moved to the io and os packages. While you can still use io/ioutil, the io and os packages provide better definitions.
  • The Delve debugger has been rebased to 1.6.0 and now supports Go 1.16.7 Toolset.

For more information, see Using Go Toolset.

(BZ#1938071)

Rust Toolset rebased to version 1.54.0

Rust Toolset has been updated to version 1.54.0. Notable changes include:

  • The Rust standard library is now available for the wasm32-unknown-unknown target. With this enhancement, you can generate WebAssembly binaries, including newly stabilized intrinsics.
  • Rust now includes the IntoIterator implementation for arrays. With this enhancement, you can use the IntoIterator trait to iterate over arrays by value and pass arrays to methods. However, array.into_iter() still iterates values by reference until the 2021 edition of Rust.
  • The syntax for or patterns now allows nesting anywhere in the pattern. For example: Pattern(1|2) instead of Pattern(1)|Pattern(2).
  • Unicode identifiers can now contain all valid identifier characters as defined in the Unicode Standard Annex #31.
  • Methods and trait implementations have been stabilized.
  • Incremental compilation is re-enabled by default.

For more information, see Using Rust Toolset.

(BZ#1945805)

LLVM Toolset rebased to version 12.0.1

LLVM Toolset has been upgraded to version 12.0.1. Notable changes include:

  • The new compiler flag -march=x86-64-v[234] has been added.
  • The compiler flag -fasynchronous-unwind-tables of the Clang compiler is now the default on Linux AArch64/PowerPC.
  • The Clang compiler now supports the C++20 likelihood attributes [[likely]] and [[unlikely]].
  • The new function attribute tune-cpu has been added. It allows microarchitectural optimizations to be applied independently from the target-cpu attribute or TargetMachine CPU.
  • The new sanitizer -fsanitize=unsigned-shift-base has been added to the integer sanitizer -fsanitize=integer to improve security.
  • Code generation on PowerPC targets has been optimized.
  • The WebAssembly backend is now enabled in LLVM. With this enhancement, you can generate WebAssembly binaries with LLVM and Clang.

For more information, see Using LLVM Toolset.

(BZ#1927937)

CMake rebased to version 3.20.2

CMake has been rebased from 3.18.2 to 3.20.2. To use CMake on a project that requires the version 3.20.2 or less, use the command cmake_minimum_required(version 3.20.2).

Notable changes include:

  • C++23 compiler modes can now be specified by using the target properties CXX_STANDARD, CUDA_STANDARD, OBJCXX_STANDARD, or by using the cxx_std_23 meta-feature of the compile features function.
  • CUDA language support now allows the NVIDIA CUDA compiler to be a symbolic link.
  • The Intel oneAPI NextGen LLVM compilers are now supported with the IntelLLVM compiler ID .
  • CMake now facilitates cross compiling for Android by merging with the Android NDK’s toolchain file.
  • When running cmake(1) to generate a project build system, unknown command-line arguments starting with a hyphen are now rejected.

For further information on new features and deprecated functionalities, see the CMake Release Notes.

(BZ#1957947)

New GCC Toolset 11

GCC Toolset 11 is a compiler toolset that provides recent versions of development tools. It is available as an Application Stream in the form of a Software Collection in the AppStream repository.

The following components have been rebased since GCC Toolset 10:

  • GCC to version 11.2
  • GDB to version 10.2
  • Valgrind to version 3.17.0
  • SystemTap to version 4.5
  • binutils to version 2.36
  • elfutils to version 0.185
  • dwz to version 0.14
  • Annobin to version 9.85

For a complete list of components, see GCC Toolset 11.

To install GCC Toolset 11, run the following command as root: 

# yum install gcc-toolset-11

To run a tool from GCC Toolset 11: 

$ scl enable gcc-toolset-11 tool

To run a shell session where tool versions from GCC Toolset 11 override system versions of these tools: 

$ scl enable gcc-toolset-11 bash

For more information, see Using GCC Toolset.

The GCC Toolset 11 components are also available in the two container images:

  • rhel8/gcc-toolset-11-toolchain, which includes the GCC compiler, the GDB debugger, and the make automation tool.
  • rhel8/gcc-toolset-11-perftools, which includes the performance monitoring tools, such as SystemTap and Valgrind.

To pull a container image, run the following command as root: 

# podman pull registry.redhat.io/<image_name>

Note that only the GCC Toolset 11 container images are now supported. Container images of earlier GCC Toolset versions are deprecated.

(BZ#1953094)

.NET updated to version 6.0

Red Hat Enterprise Linux 8.5 is distributed with .NET version 6.0. Notable improvements include:

  • Support for 64-bit Arm (aarch64)
  • Support for IBM Z and LinuxONE (s390x)

For more information, see Release Notes for .NET 6.0 RPM packages and Release Notes for .NET 6.0 containers.

(BZ#2022794)

GCC Toolset 11: GCC rebased to version 11.2

In GCC Toolset 11, the GCC package has been updated to version 11.2. Notable bug fixes and enhancements include:

General improvements

  • GCC now defaults to the DWARF Version 5 debugging format.
  • Column numbers shown in diagnostics represent real column numbers by default and respect multicolumn characters.
  • The straight-line code vectorizer considers the whole function when vectorizing.
  • A series of conditional expressions that compare the same variable can be transformed into a switch statement if each of them contains a comparison expression.

  • Interprocedural optimization improvements:

    • A new IPA-modref pass, controlled by the -fipa-modref option, tracks side effects of function calls and improves the precision of points-to analysis.
    • The identical code folding pass, controlled by the -fipa-icf option, was significantly improved to increase the number of unified functions and reduce compile-time memory use.

  • Link-time optimization improvements:

    • Memory allocation during linking was improved to reduce peak memory use.
  • Using a new GCC_EXTRA_DIAGNOSTIC_OUTPUT environment variable in IDEs, you can request machine-readable “fix-it hints” without adjusting build flags.
  • The static analyzer, run by the -fanalyzer option, is improved significantly with numerous bug fixes and enhancements provided.

Language-specific improvements

C family

  • C and C++ compilers support non-rectangular loop nests in OpenMP constructs and the allocator routines of the OpenMP 5.0 specification.

  • Attributes:

    • The new no_stack_protector attribute marks functions that should not be instrumented with stack protection (-fstack-protector).
    • The improved malloc attribute can be used to identify allocator and deallocator API pairs.

  • New warnings:

    • -Wsizeof-array-div, enabled by the -Wall option, warns about divisions of two sizeof operators when the first one is applied to an array and the divisor does not equal the size of the array element.
    • -Wstringop-overread, enabled by default, warns about calls to string functions that try to read past the end of the arrays passed to them as arguments.

  • Enhanced warnings:

    • -Wfree-nonheap-object detects more instances of calls to deallocation functions with pointers not returned from a dynamic memory allocation function.
    • -Wmaybe-uninitialized diagnoses the passing of pointers and references to uninitialized memory to functions that take const-qualified arguments.
    • -Wuninitialized detects reads from uninitialized dynamically allocated memory.

C

  • Several new features from the upcoming C2X revision of the ISO C standard are supported with the -std=c2x and -std=gnu2x options. For example:

    • The standard attribute is supported.
    • The __has_c_attribute preprocessor operator is supported.
    • Labels may appear before declarations and at the end of a compound statement.

C++

  • The default mode is changed to -std=gnu++17.
  • The C++ library libstdc++ has improved C++17 support now.

  • Several new C++20 features are implemented. Note that C++20 support is experimental.

    For more information about the features, see C++20 Language Features.

  • The C++ front end has experimental support for some of the upcoming C++23 draft features.

  • New warnings:

    • -Wctad-maybe-unsupported, disabled by default, warns about performing class template argument deduction on a type with no deduction guides.
    • -Wrange-loop-construct, enabled by -Wall, warns when a range-based for loop is creating unnecessary and resource inefficient copies.
    • -Wmismatched-new-delete, enabled by -Wall, warns about calls to operator delete with pointers returned from mismatched forms of operator new or from other mismatched allocation functions.
    • -Wvexing-parse, enabled by default, warns about the most vexing parse rule: the cases when a declaration looks like a variable definition, but the C++ language requires it to be interpreted as a function declaration.

Architecture-specific improvements

The 64-bit ARM architecture

  • The Armv8-R architecture is supported through the -march=armv8-r option.
  • GCC can autovectorize operations performing addition, subtraction, multiplication, and the accumulate and subtract variants on complex numbers.

AMD and Intel 64-bit architectures

  • The following Intel CPUs are supported: Sapphire Rapids, Alder Lake, and Rocket Lake.
  • New ISA extension support for Intel AVX-VNNI is added. The -mavxvnni compiler switch controls the AVX-VNNI intrinsics.
  • AMD CPUs based on the znver3 core are supported with the new -march=znver3 option.
  • Three microarchitecture levels defined in the x86-64 psABI supplement are supported with the new -march=x86-64-v2, -march=x86-64-v3, and -march=x86-64-v4 options.

(BZ#1946782)

GCC Toolset 11: dwz now supports DWARF 5

In GCC Toolset 11, the dwz tool now supports the DWARF Version 5 debugging format.

(BZ#1948709)

GCC Toolset 11: GCC now supports the AIA user interrupts

In GCC Toolset 11, GCC now supports the Accelerator Interfacing Architecture (AIA) user interrupts.

(BZ#1927516)

GCC Toolset 11: Generic SVE tuning defaults improved

In GCC Toolset 11, generic SVE tuning defaults have been improved on the 64-bit ARM architecture.

(BZ#1979715)

SystemTap rebased to version 4.5

The SystemTap package has been updated to version 4.5. Notable bug fixes and enhancements include:

  • 32-bit floating-point variables are automatically widened to double variables and, as a result, can be accessed directly as $context variables.
  • enum values can be accessed as $context variables.
  • The BPF uconversions tapset has been extended and includes more tapset functions to access values in user space, for example user_long_error().
  • Concurrency control has been significantly improved to provide stable operation on large servers.

For further information, see the upstream SystemTap 4.5 release notes.

(BZ#1933889)

elfutils rebased to version 0.185

The elfutils package has been updated to version 0.185. Notable bug fixes and enhancements include:

  • The eu-elflint and eu-readelf tools now recognize and show the SHF_GNU_RETAIN and SHT_X86_64_UNWIND flags on ELF sections.
  • The DEBUGINFOD_SONAME macro has been added to debuginfod.h. This macro can be used with the dlopen function to load the libdebuginfod.so library dynamically from an application.
  • A new function debuginfod_set_verbose_fd has been added to the debuginfod-client library. This function enhances the debuginfod_find_* queries functionality by redirecting the verbose output to a separate file.
  • Setting the DEBUGINFOD_VERBOSE environment variable now shows more information about which servers the debuginfod client connects to and the HTTP responses of those servers.
  • The debuginfod server provides a new thread-busy metric and more detailed error metrics to make it easier to inspect processes that run on the debuginfod server.
  • The libdw library now transparently handles the DW_FORM_indirect location value so that the dwarf_whatform function returns the actual FORM of an attribute.
  • To reduce network traffic, the debuginfod-client library stores negative results in a cache, and client objects can reuse an existing connection.

(BZ#1933890)

Valgrind rebased to version 3.17.0

The Valgrind package has been updated to version 3.17.0. Notable bug fixes and enhancements include:

  • Valgrind can read the DWARF Version 5 debugging format.
  • Valgrind supports debugging queries to the debuginfod server.
  • The ARMv8.2 processor instructions are partially supported.
  • The Power ISA v.3.1 instructions on POWER10 processors are partially supported.
  • The IBM z14 processor instructions are supported.
  • Most IBM z15 instructions are supported. The Valgrind tool suite supports the miscellaneous-instruction-extensions facility 3 and the vector-enhancements facility 2 for the IBM z15 processor. As a result, Valgrind runs programs compiled with GCC -march=z15 correctly and provides improved performance and debugging experience.
  • The --track-fds=yes option respects -q (--quiet) and ignores the standard file descriptors stdin, stdout, and stderr by default. To track the standard file descriptors, use the --track-fds=all option.
  • The DHAT tool has two new modes of operation: --mode=copy and --mode=ad-hoc.

(BZ#1933891)

Dyninst rebased to version 11.0.0

The Dyninst package has been updated to version 11.0.0. Notable bug fixes and enhancements include:

  • Support for the debuginfod server and for fetching separate debuginfo files.
  • Improved detection of indirect calls to procedure linkage table (PLT) stubs.
  • Improved C++ name demangling.
  • Fixed memory leaks during code emitting.

(BZ#1933893)

DAWR functionality improved in GDB on IBM POWER10

With this enhancement, new hardware watchpoint capabilities are now enabled for GDB on the IBM POWER10 processors. For example, a new set of DAWR/DAWRX registers has been added.

(BZ#1854784)

GCC Toolset 11: GDB rebased to version 10.2

In GCC Toolset 11, the GDB package has been updated to version 10.2. Notable bug fixes and enhancements include:

New features

  • Multithreaded symbol loading is enabled by default on architectures that support this feature. This change provides better performance for programs with many symbols.
  • Text User Interface (TUI) windows can be arranged horizontally.
  • GDB supports debugging multiple target connections simultaneously but this support is experimental and limited. For example, you can connect each inferior to a different remote server that runs on a different machine, or you can use one inferior to debug a local native process or a core dump or some other process.

New and improved commands

  • A new tui new-layout name window weight [window weight…] command creates a new text user interface (TUI) layout, you can also specify a layout name and displayed windows.
  • The improved alias [-a] [--] alias = command [default-args] command can specify default arguments when creating a new alias.
  • The set exec-file-mismatch and show exec-file-mismatch commands set and show a new exec-file-mismatch option. When GDB attaches to a running process, this option controls how GDB reacts when it detects a mismatch between the current executable file loaded by GDB and the executable file used to start the process.

Python API

  • The gdb.register_window_type function implements new TUI windows in Python.
  • You can now query dynamic types. Instances of the gdb.Type class can have a new boolean attribute dynamic and the gdb.Type.sizeof attribute can have value None for dynamic types. If Type.fields() returns a field of a dynamic type, the value of its bitpos attribute can be None.
  • A new gdb.COMMAND_TUI constant registers Python commands as members of the TUI help class of commands.
  • A new gdb.PendingFrame.architecture() method retrieves the architecture of the pending frame.
  • A new gdb.Architecture.registers method returns a gdb.RegisterDescriptorIterator object, an iterator that returns gdb.RegisterDescriptor objects. Such objects do not provide the value of a register but help understand which registers are available for an architecture.
  • A new gdb.Architecture.register_groups method returns a gdb.RegisterGroupIterator object, an iterator that returns gdb.RegisterGroup objects. Such objects help understand which register groups are available for an architecture.

(BZ#1954332)

GCC Toolset 11: SystemTap rebased to version 4.5

In GCC Toolset 11, the SystemTap package has been updated to version 4.5. Notable bug fixes and enhancements include:

  • 32-bit floating-point variables are now automatically widened to double variables and, as a result, can be accessed directly as $context variables.
  • enum values can now be accessed as $context variables.
  • The BPF uconversions tapset has been extended and now includes more tapset functions to access values in user space, for example user_long_error().
  • Concurrency control has been significantly improved to provide stable operation on large servers.

For further information, see the upstream SystemTap 4.5 release notes.

(BZ#1957944)

GCC Toolset 11: elfutils rebased to version 0.185

In GCC Toolset 11, the elfutils package has been updated to version 0.185. Notable bug fixes and enhancements include:

  • The eu-elflint and eu-readelf tools now recognize and show the SHF_GNU_RETAIN and SHT_X86_64_UNWIND flags on ELF sections.
  • The DEBUGINFOD_SONAME macro has been added to debuginfod.h. This macro can be used with the dlopen function to load the libdebuginfod.so library dynamically from an application.
  • A new function debuginfod_set_verbose_fd has been added to the debuginfod-client library. This function enhances the debuginfod_find_* queries functionality by redirecting the verbose output to a separate file.
  • Setting the DEBUGINFOD_VERBOSE environment variable now shows more information about which servers the debuginfod client connects to and the HTTP responses of those servers.
  • The debuginfod server provides a new thread-busy metric and more detailed error metrics to make it easier to inspect processes that run on the debuginfod server.
  • The libdw library now transparently handles the DW_FORM_indirect location value so that the dwarf_whatform function returns the actual FORM of an attribute.
  • The debuginfod-client library now stores negative results in a cache and client objects can reuse an existing connection. This way unnecessary network traffic when using the library is prevented.

(BZ#1957225)

GCC Toolset 11: Valgrind rebased to version 3.17.0

In GCC Toolset 11, the Valgrind package has been updated to version 3.17.0. Notable bug fixes and enhancements include:

  • Valgrind can now read the DWARF Version 5 debugging format.
  • Valgrind now supports debugging queries to the debuginfod server.
  • Valgrind now partially supports the ARMv8.2 processor instructions.
  • Valgrind now supports the IBM z14 processor instructions.
  • Valgrind now partially supports the Power ISA v.3.1 instructions on POWER10 processors.
  • The --track-fds=yes option now respects -q (--quiet) and ignores the standard file descriptors stdin, stdout, and stderr by default. To track the standard file descriptors, use the --track-fds=all option.
  • The DHAT tool now has two new modes of operation: --mode=copy and --mode=ad-hoc.

(BZ#1957226)

GCC Toolset 11: Dyninst rebased to version 11.0.0

In GCC Toolset 11, the Dyninst package has been updated to version 11.0.0. Notable bug fixes and enhancements include:

  • Support for the debuginfod server and for fetching separate debuginfo files.
  • Improved detection of indirect calls to procedure linkage table (PLT) stubs.
  • Improved C++ name demangling.
  • Fixed memory leaks during code emitting.

(BZ#1957942)

PAPI library support for Fujitsu A64FX added

PAPI library support for Fujitsu A64FX has been added. With this feature, developers can collect hardware statistics.

(BZ#1908126)

The PCP package was rebased to 5.3.1

The Performance Co-Pilot (PCP) package has been rebased to version 5.3.1. This release includes bug fixes, enhancements, and new features. Notable changes include:

  • Scalability improvements, which now support centrally logged performance metrics for hundreds of hosts (pmlogger farms) and automatic monitoring with performance rules (pmie farms).
  • Resolved memory leaks in the pmproxy service and the libpcp_web API library, and added instrumentation and new metrics to pmproxy.
  • A new pcp-ss tool for historical socket statistics.
  • Improvements to the pcp-htop tool.
  • Extensions to the over-the-wire PCP protocol which now support higher resolution timestamps.

(BZ#1922040)

The grafana package was rebased to version 7.5.9

The grafana package has been rebased to version 7.5.9. Notable changes include:

  • New time series panel (beta)
  • New pie chart panel (beta)
  • Alerting support for Loki
  • Multiple new query transformations

For more information, see What’s New in Grafana v7.4, What’s New in Grafana v7.5.

(BZ#1921191)

The grafana-pcp package was rebased to 3.1.0

The grafana-pcp package has been rebased to version 3.1.0. Notable changes include:

  • Performance Co-Pilot (PCP) Vector Checklist dashboards use a new time series panel, show units in graphs, and contain updated help texts.
  • Adding pmproxy URL and hostspec variables to PCP Vector Host Overview and PCP Checklist dashboards.
  • All dashboards display datasource selection.
  • Marking all included dashboards as readonly.
  • Adding compatibility with Grafana 8.

(BZ#1921190)

grafana-container rebased to version 7.5.9

The rhel8/grafana container image provides Grafana. Notable changes include:

  • The grafana package is now updated to version 7.5.9.
  • The grafana-pcp package is now updated to version 3.1.0.
  • The container now supports the GF_INSTALL_PLUGINS environment variable to install custom Grafana plugins at container startup

The rebase updates the rhel8/grafana image in the Red Hat Container Registry.

To pull this container image, execute the following command: 

# podman pull registry.redhat.io/rhel8/grafana

(BZ#1971557)

pcp-container rebased to version 5.3.1

The rhel8/pcp container image provides Performance Co-Pilot. The pcp-container package has been upgraded to version 5.3.1. Notable changes include:

  • The pcp package is now updated to version 5.3.1.

The rebase updates the rhel8/pcp image in the Red Hat Container Registry.

To pull this container image, execute the following command: 

# podman pull registry.redhat.io/rhel8/pcp

(BZ#1974912)

The new pcp-ss PCP utility is now available

The pcp-ss PCP utility reports socket statistics collected by the pmdasockets(1) PMDA. The command is compatible with many of the ss command line options and reporting formats. It also offers the advantages of local or remote monitoring in live mode and historical replay from a previously recorded PCP archive.

(BZ#1879350)

Power consumption metrics now available in PCP

The new pmda-denki Performance Metrics Domain Agent (PMDA) reports metrics related to power consumption. Specifically, it reports:

  • Consumption metrics based on Running Average Power Limit (RAPL) readings, available on recent Intel CPUs
  • Consumption metrics based on battery discharge, available on systems which have a battery

(BZ#1629455)

4.13. Identity Management

IdM now supports new password policy options

With this update, Identity Management (IdM) supports additional libpwquality library options:

--maxrepeat
Specifies the maximum number of the same character in sequence.
--maxsequence
Specifies the maximum length of monotonic character sequences (abcd).
--dictcheck
Checks if the password is a dictionary word.
--usercheck
Checks if the password contains the username.

Use the ipa pwpolicy-mod command to apply these options. For example, to apply the user name check to all new passwords suggested by the users in the managers group: 

*$ ipa pwpolicy-mod --usercheck=True managers*

If any of the new password policy options are set, then the minimum length of passwords is 6 characters regardless of the value of the --minlength option. The new password policy settings are applied only to new passwords.

In a mixed environment with RHEL 7 and RHEL 8 servers, the new password policy settings are enforced only on servers running on RHEL 8.4 and later. If a user is logged in to an IdM client and the IdM client is communicating with an IdM server running on RHEL 8.3 or earlier, then the new password policy requirements set by the system administrator will not be applied. To ensure consistent behavior, upgrade or update all servers to RHEL 8.4 and later.

(JIRA:RHELPLAN-89566)

Improved the SSSD debug logging by adding a unique identifier tag for each request

As SSSD processes requests asynchronously, it is not easy to follow log entries for individual requests in the backend logs, as messages from different requests are added to the same log file. To improve the readability of debug logs, a unique request identifier is now added to log messages in the form of RID#<integer>. This allows you to isolate logs pertaining to an individual request, and you can track requests from start to finish across log files from multiple SSSD components.

For example, the following sample output from an SSSD log file shows the unique identifiers RID#3 and RID#4 for two different requests: 

(2021-07-26 18:26:37): [be[testidm.com]] [dp_req_destructor] (0x0400): RID#3 Number of active DP request: 0
(2021-07-26 18:26:37): [be[testidm.com]] [dp_req_reply_std] (0x1000): RID#3 DP Request AccountDomain #3: Returning [Internal Error]: 3,1432158301,GetAccountDomain() not supported
(2021-07-26 18:26:37): [be[testidm.com]] [dp_attach_req] (0x0400): RID#4 DP Request Account #4: REQ_TRACE: New request. sssd.nss CID #1 Flags [0x0001].
(2021-07-26 18:26:37): [be[testidm.com]] [dp_attach_req] (0x0400): RID#4 Number of active DP request: 1

(JIRA:RHELPLAN-92473)

IdM now supports the automember and server Ansible modules

With this update, the ansible-freeipa package contains the ipaautomember and ipaserver modules:

  • Using the ipaautomember module, you can add, remove, and modify automember rules and conditions. As a result, future IdM users and hosts that meet the conditions will be assigned to IdM groups automatically.
  • Using the ipaserver module, you can ensure various parameters of the presence or absence of a server in the IdM topology. You can also ensure that a replica is hidden or visible.

(JIRA:RHELPLAN-96640)

IdM performance baseline

With this update, a RHEL 8.5 IdM server with 4 CPUs and 8GB of RAM has been tested to successfully enroll 130 IdM clients simultaneously.

(JIRA:RHELPLAN-97145)

SSSD Kerberos cache performance has been improved

The System Security Services Daemon (SSSD) Kerberos Cache Manager (KCM) service now includes the new operation KCM_GET_CRED_LIST. This enhancement improves KCM performance by reducing the number of input and output operations while iterating through a credentials cache.

(BZ#1956388)

SSSD now logs backtraces by default

With this enhancement, SSSD now stores detailed debug logs in an in-memory buffer and appends them to log files when a failure occurs. By default, the following error levels trigger a backtrace:

  • Level 0: fatal failures
  • Level 1: critical failures
  • Level 2: serious failures

You can modify this behavior for each SSSD process by setting the debug_level option in the corresponding section of the sssd.conf configuration file:

  • If you set the debugging level to 0, only level 0 events trigger a backtrace.
  • If you set the debugging level to 1, levels 0 and 1 trigger a backtrace.
  • If you set the debugging level to 2 or higher, events at level 0 through 2 trigger a backtrace.

You can disable this feature per SSSD process by setting the debug_backtrace_enabled option to false in the corresponding section of sssd.conf: 

[sssd]
debug_backtrace_enabled = true
debug_level=0
...

[nss]
debug_backtrace_enabled = false
...

[domain/idm.example.com]
debug_backtrace_enabled = true
debug_level=2
...

...

(BZ#1949149)

SSSD KCM now supports the auto-renewal of ticket granting tickets

With this enhancement, you can now configure the System Security Services Daemon (SSSD) Kerberos Cache Manager (KCM) service to auto-renew ticket granting tickets (TGTs) stored in the KCM credential cache on an Identity Management (IdM) server. Renewals are only attempted when half of the ticket lifetime has been reached. To use auto-renewal, the key distribution center (KDC) on the IdM server must be configured to support renewable Kerberos tickets.

You can enable TGT auto-renewal by modifying the [kcm] section of the /etc/sssd/sssd.conf file. For example, you can configure SSSD to check for renewable KCM-stored TGTs every 60 minutes and attempt auto-renewal if half of the ticket lifetime has been reached by adding the following options to the file: 

[kcm]
tgt_renewal = true
krb5_renew_interval = 60m

Alternatively, you can configure SSSD to inherit krb5 options for renewals from an existing domain: 

[kcm]
tgt_renewal = true
tgt_renewal_inherit = domain-name

For more information, see the Renewals section of the sssd-kcm man page.

(BZ#1627112)

samba rebased to version 4.14.4

The _samba_ packages have been upgraded to upstream version 4.14.4, which provides bug fixes and enhancements over the previous version:

  • Publishing printers in Active Directory (AD) has increased reliability, and additional printer features have been added to the published information in AD. Also, Samba now supports Windows drivers for the ARM64 architecture.
  • The ctdb isnotrecmaster command has been removed. As an alternative, use ctdb pnn or the ctdb recmaster commands.
  • The clustered trivial database (CTDB) ctdb natgw master and slave-only parameters have been renamed to ctdb natgw leader and follower-only.

Back up the database files before starting Samba. When the smbd, nmbd, or winbind services start Samba automatically updates its tdb database files. Note that Red Hat does not support downgrading tdb database files.

After updating Samba, verify the /etc/samba/smb.conf file using the testparm utility.

For further information about notable changes, read the upstream release notes before updating.

(BZ#1944657)

The dnaInterval configuration attribute is now supported

With this update, Red Hat Directory Server supports setting the dnaInterval attribute of the Distributed Numeric Assignment (DNA) plug-in in the cn=<DNA_config_entry>,cn=Distributed Numeric Assignment Plugin,cn=plugins,cn=config entry. The DNA plug-in generates unique values for specified attributes. In a replication environment, servers can share the same range. To avoid overlaps on different servers, you can set the dnaInterval attribute to skip some values. For example, if the interval is 3 and the first number in the range is 1, the next number used in the range is 4, then 7, then 10.

For further details, see the dnaInterval parameter description.

(BZ#1938239)

Directory Server rebased to version 1.4.3.27

The 389-ds-base packages have been upgraded to upstream version 1.4.3.27, which provides a number of bug fixes and enhancements over the previous version. For a complete list of notable changes, read the upstream release notes before updating:

(BZ#1947044)

Directory Server now supports temporary passwords

This enhancement enables administrators to configure temporary password rules in global and local password policies. With these rules, you can configure that, when an administrator resets the password of a user, the password is temporary and only valid for a specific time and for a defined number of attempts. Additionally, you can configure that the expiration time does not start directly when the administrator changes the password. As a result, Directory Server allows the user only to authenticate using the temporary password for a finite period of time or attempts. Once the user authenticates successfully, Directory Server allows this user only to change its password.

(BZ#1626633)

IdM KDC now issues Kerberos tickets with PAC information to increase security

With this update, to increase security, RHEL Identity Management (IdM) now issues Kerberos tickets with Privilege Attribute Certificate (PAC) information by default in new deployments. A PAC has rich information about a Kerberos principal, including its Security Identifier (SID), group memberships, and home directory information. As a result, Kerberos tickets are less susceptible to manipulation by malicious servers.

SIDs, which Microsoft Active Directory (AD) uses by default, are globally unique identifiers that are never reused. SIDs express multiple namespaces: each domain has a SID, which is a prefix in the SID of each object.

Starting with RHEL 8.5, when you install an IdM server or replica, the installation script generates SIDs for users and groups by default. This allows IdM to work with PAC data. If you installed IdM before RHEL 8.5, and you have not configured a trust with an AD domain, you may not have generated SIDs for your IdM objects. For more information about generating SIDs for your IdM objects, see Enabling Security Identifiers (SIDs) in IdM.

By evaluating PAC information in Kerberos tickets, you can control resource access with much greater detail. For example, the Administrator account in one domain has a uniquely different SID than the Administrator account in any other domain. In an IdM environment with a trust to an AD domain, you can set access controls based on globally unique SIDs rather than simple user names or UIDs that might repeat in different locations, such as every Linux root account having a UID of 0.

(Jira:RHELPLAN-159143)

Directory Server provides monitoring settings that can prevent database corruption caused by lock exhaustion

This update adds the nsslapd-db-locks-monitoring-enable parameter to the cn=bdb,cn=config,cn=ldbm database,cn=plugins,cn=config entry. If it is enabled, which is the default, Directory Server aborts all of the searches if the number of active database locks is higher than the percentage threshold configured in nsslapd-db-locks-monitoring-threshold. If an issue is encountered, the administrator can increase the number of database locks in the nsslapd-db-locks parameter in the cn=bdb,cn=config,cn=ldbm database,cn=plugins,cn=config entry. This can prevent data corruption. Additionally, the administrator now can set a time interval in milliseconds that the thread sleeps between the checks.

For further details, see the parameter descriptions in the Red Hat Directory Server Configuration, Command, and File Reference.

(BZ#1812286)

Directory Server can exclude attributes and suffixes from the retro changelog database

This enhancement adds the nsslapd-exclude-attrs and nsslapd-exclude-suffix parameters to Directory Server. You can set these parameters in the cn=Retro Changelog Plugin,cn=plugins,cn=config entry to exclude certain attributes or suffixes from the retro changelog database.

(BZ#1850664)

Directory Server supports the entryUUID attribute

With this enhancement, Directory Server supports the entryUUID attribute to be compliant with RFC 4530. For example, with support for entryUUID, migrations from OpenLDAP are easier. By default, Directory Server adds the entryUUID attribute only to new entries. To manually add it to existing entries, use the dsconf <instance_name> plugin entryuuid fixup command.

(BZ#1944494)

Added a new message to help set up nsSSLPersonalitySSL

Previously, many times happened that RHDS instance failed to start if the TLS certificate nickname didn’t match the value of the configuration parameter nsSSLPersonalitySSL. This mismatch happened when customer copy the NSS DB from a previous instance or export the certificate’s data but forget to set the nsSSLPersonalitySSL value accordingly. With this update, you can see log an additional message which should help a user to set up nsSSLPersonalitySSL correctly.

(BZ#1895460)

4.14. Desktop

You can now connect to network at the login screen

With this update, you can now connect to your network and configure certain network options at the GNOME Display Manager (GDM) login screen. As a result, you can log in as an enterprise user whose home directory is stored on a remote server.

The login screen supports the following network options:

  • Wired network
  • Wireless network, including networks protected by a password
  • Virtual Private Network (VPN)

The login screen cannot open windows for additional network configuration. As a consequence, you cannot use the following network options at the login screen:

  • Networks that open a captive portal
  • Modem connections
  • Wireless networks with enterprise WPA or WPA2 encryption that have not been preconfigured

The network options at the login screen are disabled by default. To enable the network settings, use the following procedure:

  1. Create the /etc/polkit-1/rules.d/org.gnome.gdm.rules file with the following content: 

    polkit.addRule(function(action, subject) {
    if (action.id == "org.freedesktop.NetworkManager.network-control" &&
        subject.user == "gdm") {
            return polkit.Result.YES;
    }

    return polkit.Result.NOT_HANDLED;
});

  2. Restart GDM: 

    # systemctl restart gdm
    Warning

    Restarting GDM terminates all your graphical user sessions.

  3. At the login screen, access the network settings in the menu on the right side of the top panel.

(BZ#1935261)

Displaying the system security classification at login

You can now configure the GNOME Display Manager (GDM) login screen to display an overlay banner that contains a predefined message. This is useful for deployments where the user is required to read the security classification of the system before logging in.

To enable the overlay banner and configure a security classification message, use the following procedure:

  1. Install the gnome-shell-extension-heads-up-display package: 

    # yum install gnome-shell-extension-heads-up-display

  2. Create the /etc/dconf/db/gdm.d/99-hud-message file with the following content: 

    [org/gnome/shell]
enabled-extensions=['heads-up-display@gnome-shell-extensions.gcampax.github.com']

[org/gnome/shell/extensions/heads-up-display]
message-heading="Security classification title"
message-body="Security classification description"

    Replace the following values with text that describes the security classification of your system:

    Security classification title
    A short heading that identifies the security classification.
    Security classification description
    A longer message that provides additional details, such as references to various guidelines.

  3. Update the dconf database: 

    # dconf update
  4. Reboot the system.

(BZ#1651378)

Flicker free boot is available

You can now enable flicker free boot on your system. When flicker free boot is enabled, it eliminates abrupt graphical transitions during the system boot process, and the display does not briefly turn off during boot.

To enable flicker free boot, use the following procedure:

  1. Configure the boot loader menu to hide by default: 

    # grub2-editenv - set menu_auto_hide=1

  2. Update the boot loader configuration:

    • On UEFI systems: 

      # grub2-mkconfig -o /etc/grub2-efi.cfg

    • On legacy BIOS systems: 

      # grub2-mkconfig -o /etc/grub2.cfg
  3. Reboot the system.

As a result, the boot loader menu does not display during system boot, and the boot process is graphically smooth.

To access the boot loader menu, repeatedly press Esc after turning on the system.

(JIRA:RHELPLAN-99148)

Updated support for emoji

This release updates support for Unicode emoji characters from version 11 to version 13 of the emoji standard. As a result, you can now use more emoji characters on RHEL.

The following packages that provide emoji functionality have been rebased:

PackagePrevious versionRebased to version

cldr-emoji-annotation

33.1.0

38

google-noto-emoji-fonts

20180508

20200723

unicode-emoji

10.90.20180207

13.0

(JIRA:RHELPLAN-61867)

You can set a default desktop session for all users

With this update, you can now configure a default desktop session that is preselected for all users that have not logged in yet.

If a user logs in using a different session than the default, their selection persists to their next login.

To configure the default session, use the following procedure:

  1. Copy the configuration file template: 

    # cp /usr/share/accountsservice/user-templates/standard \
     /etc/accountsservice/user-templates/standard
  2. Edit the new /etc/accountsservice/user-templates/standard file. On the Session=gnome line, replace gnome with the session that you want to set as the default.

  3. Optional: To configure an exception to the default session for a certain user, follow these steps:

    1. Copy the template file to /var/lib/AccountsService/users/user-name: 

      # cp /usr/share/accountsservice/user-templates/standard \
     /var/lib/AccountsService/users/user-name
    2. In the new file, replace variables such as ${USER} and ${ID} with the user values.
    3. Edit the Session value.

(BZ#1812788)

4.15. Graphics infrastructures

Support for new GPUs

The following new GPUs are now supported.

Intel graphics:

  • Alder Lake-S (ADL-S)

    Support for Alder Lake-S graphics is disabled by default. To enable it, add the following option to the kernel command line: 

    i915.force_probe=PCI_ID

    Replace PCI_ID with either the PCI device ID of your Intel GPU, or with the * character to enable support for all alpha-quality hardware that uses the i915 driver.

  • Elkhart Lake (EHL)
  • Comet Lake Refresh (CML-R) with the TGP Platform Controller Hub (PCH)

AMD graphics:

  • Cezzane and Barcelo
  • Sienna Cichlid
  • Dimgrey Cavefish

(JIRA:RHELPLAN-99040, BZ#1784132, BZ#1784136, BZ#1838558)

The Wayland session is available with the proprietary NVIDIA driver

The proprietary NVIDIA driver now supports hardware accelerated OpenGL and Vulkan rendering in Xwayland. As a result, you can now enable the GNOME Wayland session with the proprietary NVIDIA driver. Previously, only the legacy X11 session was available with the driver. X11 remains as the default session to avoid a possible disruption when updating from a previous version of RHEL.

To enable Wayland with the NVIDIA proprietary driver, use the following procedure:

  1. Enable Direct Rendering Manager (DRM) kernel modesetting by adding the following option to the kernel command line: 

    nvidia-drm.modeset=1

    For details on enabling kernel options, see Configuring kernel command-line parameters.

  2. Reboot the system.

    The Wayland session is now available at the login screen.

  3. Optional: To avoid the loss of video allocations when suspending or hibernating the system, enable the power management option with the driver. For details, see Configuring Power Management Support.

For the limitations related to the use of DRM kernel modesetting in the proprietary NVIDIA driver, see Direct Rendering Manager Kernel Modesetting (DRM KMS).

(JIRA:RHELPLAN-99049)

Improvements to GPU support

The following new GPU features are now enabled:

  • Panel Self Refresh (PSR) is now enabled for Intel Tiger Lake and later graphics, which improves power consumption.
  • Intel Tiger Lake, Ice Lake, and later graphics can now use High Bit Rate 3 (HBR3) mode with the DisplayPort Multi-Stream Transport (DP-MST) transmission method. This enables support for certain display capabilities with docks.
  • Modesetting is now enabled on NVIDIA Ampere GPUs. This includes the following models: GA102, GA104, and GA107, including hybrid graphics systems.
  • Most laptops with Intel integrated graphics and an NVIDIA Ampere GPU can now output to external displays using either GPU.

(JIRA:RHELPLAN-99043)

Updated graphics drivers

The following graphics drivers have been updated:

  • amdgpu
  • ast
  • i915
  • mgag2000
  • nouveau
  • vmwgfx
  • vmwgfx
  • The Mesa library
  • Vulkan packages

(JIRA:RHELPLAN-99044)

Intel Tiger Lake graphics are fully supported

Intel Tiger Lake UP3 and UP4 Xe graphics, which were previously available as a Technology Preview, are now fully supported. Hardware acceleration is enabled by default on these GPUs.

(BZ#1783396)

4.16. Red Hat Enterprise Linux system roles

Users can configure the maximum root distance using the timesync_max_distance parameter

With this update, the timesync RHEL system role is able to configure the tos maxdist of ntpd and the maxdistance parameter of the chronyd service using the new timesync_max_distance parameter. The timesync_max_distance parameter configures the maximum root distance to accept measurements from Network Time Protocol (NTP) servers. The default value is 0, which keeps the provider-specific defaults.

(BZ#1938016)

Elasticsearch can now accept lists of servers

Previously, the server_host parameter in Elasticsearch output for the Logging RHEL system role accepted only a string value for a single host. With this enhancement, it also accepts a list of strings to support multiple hosts. As a result, you can now configure multiple Elasticsearch hosts in one Elasticsearch output dictionary.

(BZ#1986463)

Network Time Security (NTS) option added to the timesync RHEL system role

The nts option was added to the timesync RHEL system role to enable NTS on client servers. NTS is a new security mechanism specified for Network Time Protocol (NTP), which can secure synchronization of NTP clients without client-specific configuration and can scale to large numbers of clients. The NTS option is supported only with the chrony NTP provider in version 4.0 and later.

(BZ#1970664)

The SSHD RHEL system role now supports non-exclusive configuration snippets

With this feature, you can configure SSHD through different roles and playbooks without rewriting the previous configurations by using namespaces. Namespaces are similar to a drop-in directory, and define non-exclusive configuration snippets for SSHD. As a result, you can use the SSHD RHEL system role from a different role, if you need to configure only a small part of the configuration and not the entire configuration file.

(BZ#1970642)

The SELinux role can now manage SELinux modules

The SElinux RHEL system role has the ability to manage SELinux modules. With this update, users can provide their own custom modules from .pp or .cil files, which allows for a more flexible SELinux policy management.

(BZ#1848683)

Users can manage the chrony interleaved mode, NTP filtering, and hardware timestamping

With this update, the timesync RHEL system role enables you to configure the Network Time Protocol (NTP) interleaved mode, additional filtering of NTP measurements, and hardware timestamping. The chrony package of version 4.0 adds support for these functionalities to achieve a highly accurate and stable synchronization of clocks in local networks.

  • To enable the NTP interleaved mode, make sure the server supports this feature, and set the xleave option to yes for the server in the timesync_ntp_servers list. The default value is no.
  • To set the number of NTP measurements per clock update, set the filter option for the NTP server you are configuring. The default value is 1.
  • To set the list of interfaces which should have hardware timestamping enabled for NTP, use the timesync_ntp_hwts_interfaces parameter. The special value ["*"] enables timestamping on all interfaces that support it. The default is [].

(BZ#1938020)

timesync role enables customization settings for chrony

Previously, there was no way to provide customized chrony configuration using the timesync role. This update adds the timesync_chrony_custom_settings parameter, which enables users to to provide customized settings for chrony, such as: 

timesync_chrony_custom_settings:
  - "logdir /var/log/chrony"
  - "log measurements statistics tracking"

(BZ#1938023)

timesync role supports hybrid end-to-end delay mechanisms

With this enhancement, you can use the new hybrid_e2e option in timesync_ptp_domains to enable hybrid end-to-end delay mechanisms in the timesync role. The hybrid end-to-end delay mechanism uses unicast delay requests, which are useful to reduce multicast traffic in large networks.

(BZ#1957849)

ethtool now supports reducing the packet loss rate and latency

Tx or Rx buffers are memory spaces allocated by a network adapter to handle traffic bursts. Properly managing the size of these buffers is critical to reduce the packet loss rate and achieve acceptable network latency.

The ethtool utility now reduces the packet loss rate or latency by configuring the ring option of the specified network device.

The list of supported ring parameters is:

  • rx - Changes the number of ring entries for the Rx ring.
  • rx-jumbo - Changes the number of ring entries for the Rx Jumbo ring.
  • rx-mini - Changes the number of ring entries for the Rx Mini ring.
  • tx - Changes the number of ring entries for the Tx ring.

(BZ#1959649)

New ipv6_disabled parameter is now available

With this update, you can now use the ipv6_disabled parameter to disable ipv6 when configuring addresses.

(BZ#1939711)

RHEL system roles now support VPN management

Previously, it was difficult to set up secure and properly configured IPsec tunneling and virtual private networking (VPN) solutions on Linux. With this enhancement, you can use the VPN RHEL system role to set up and configure VPN tunnels for host-to-host and mesh connections more easily across large numbers of hosts. As a result, you have a consistent and stable configuration interface for VPN and IPsec tunneling configuration within the RHEL system roles project.

(BZ#1943679)

The storage RHEL system role now supports filesystem relabel

Previously, the storage role did not support relabelling. This update fixes the issue, providing support to relabel the filesystem label. To do this, set a new label string to the fs_label parameter in storage_volumes.

(BZ#1876315)

Support for volume sizes expressed as a percentage is available in the storage system role

This enhancement adds support to the storage RHEL system role to express LVM volume sizes as a percentage of the pool’s total size. You can specify the size of LVM volumes as a percentage of the pool/VG size, for example: 50% in addition to the human-readable size of the file system, for example, 10g, 50 GiB.

(BZ#1894642)

New Ansible Role for Microsoft SQL Server Management

The new microsoft.sql.server role is designed to help IT and database administrators automate processes involved with setup, configuration, and performance tuning of SQL Server on Red Hat Enterprise Linux.

(BZ#2013853)

RHEL system roles do not support Ansible 2.8

With this update, support for Ansible 2.8 is no longer supported because the version is past the end of the product life cycle. The RHEL system roles support Ansible 2.9.

(BZ#1989199)

The postfix role of RHEL system roles is fully supported

Red Hat Enterprise Linux system roles provides a configuration interface for Red Hat Enterprise Linux subsystems, which makes system configuration easier through the inclusion of Ansible Roles. This interface enables managing system configurations across multiple versions of Red Hat Enterprise Linux, as well as adopting new major releases.

The rhel-system-roles packages are distributed through the AppStream repository.

As of RHEL 8.5, the postfix role is fully supported.

For more information, see the Knowledgebase article about RHEL system roles.

(BZ#1812552)

4.17. Virtualization

Enhancements to managing virtual machines in the web console

The Virtual Machines (VM) section of the RHEL 8 web console has been redesigned for a better user experience. In addition, the following changes and features have also been introduced:

  • A single page now includes all the relevant VM information, such as VM status, disks, networks, or console information.
  • You can now live migrate a VM using the web console
  • The web console now allows editing the MAC address of a VM’s network interface
  • You can use the web console to view a list of host devices attached to a VM

(JIRA:RHELPLAN-79074)

zPCI device assignment

It is now possible to attach zPCI devices as mediated devices to virtual machines (VMs) hosted on RHEL 8 running on IBM Z hardware. For example, thís enables the use of NVMe flash drives in VMs.

(JIRA:RHELPLAN-59528)

4.18. Supportability

sos rebased to version 4.1

The sos package has been upgraded to version 4.1, which provides multiple bug fixes and enhancements. Notable enhancements include:

  • Red Hat Update Infrastructure (RHUI) plugin is now natively implemented in the sos package. With the rhui-debug.py python binary, sos can collect reports from RHUI including, for example, the main configuration file, the rhui-manager log file, or the installation configuration.
  • sos introduces the --cmd-timeout global option that sets manually a timeout for a command execution. The default value (-1) defers to the general command timeout, which is 300 seconds.

(BZ#1928679)

4.19. Containers

Default container image signature verification is now available

Previously, the policy YAML files for the Red Hat Container Registries had to be manually created in the /etc/containers/registries.d/ directory. Now, the registry.access.redhat.com.yaml and registry.redhat.io.yaml files are included in the containers-common package. You can now use the podman image trust command to verify the container image signatures on RHEL.

(JIRA:RHELPLAN-75166)

The container-tools:rhel8 module has been updated

The container-tools:rhel8 module, which contains the Podman, Buildah, Skopeo, and runc tools is now available. This update provides a list of bug fixes and enhancements over the previous version.

(JIRA:RHELPLAN-76515)

The containers-common package is now available

The containers-common package has been added to the container-tools:rhel8 module. The containers-common package contains common configuration files and documentation for container tools ecosystem, such as Podman, Buildah and Skopeo.

(JIRA:RHELPLAN-77542)

Native overlay file system support in the kernel is now available

The overlay file system support is now available from kernel 5.11. The non-root users will have native overlay performance even when running rootless (as a user). Thus, this enhancement provides better performance to non-root users who wish to use overlayfs without the need for bind mounting.

(JIRA:RHELPLAN-77241)

A podman container image is now available

The registry.redhat.io/rhel8/podman container image, previously available as a Technology Preview, is now fully supported. The registry.redhat.io/rhel8/podman container image is a containerized implementation of the podman package. The podman tool manages containers and images, volumes mounted into those containers, and pods made of groups of containers.

(JIRA:RHELPLAN-57941)

Universal Base Images are now available on Docker Hub

Previously, Universal Base Images were only available from the Red Hat container catalog. Now, Universal Base Images are also available from Docker Hub.

For more information, see Red Hat Brings Red Hat Universal Base Image to Docker Hub.

(JIRA:RHELPLAN-85064)

CNI plugins in Podman are now available

CNI plugins are now available to use in Podman rootless mode. The rootless networking commands now work without any other requirement on the system.

(BZ#1934480)

Podman has been updated to version 3.3.1

The Podman utility has been updated to version 3.3.1. Notable enhancements include:

  • Podman now supports restarting containers created with the --restart option after the system is rebooted.
  • The podman container checkpoint and podman container restore commands now support checkpointing and restoring containers that are in pods and restoring those containers into pods. Further, the podman container restore command now supports the --publish option to change ports forwarded to a container restored from an exported checkpoint.

(JIRA:RHELPLAN-87877)

The crun OCI runtime is now available

The crun OCI runtime is now available for the container-tools:rhel8 module. The crun container runtime supports an annotation that enables the container to access the rootless user’s additional groups. This is useful for container operations when volume mounting in a directory where setgid is set, or where the user only has group access.

(JIRA:RHELPLAN-75164)

The podman UBI image is now available

The registry.access.redhat.com/ubi8/podman is now available as a part of UBI.

(JIRA:RHELPLAN-77489)

The container-tools:rhel8 module has been updated

The container-tools:rhel8 module, which contains the Podman, Buildah, Skopeo, and runc tools is now available. This update provides a list of bug fixes and enhancements over the previous version.

For more details, see the RHEA-2022:0352.

(BZ#2009153)

The ubi8/nodejs-16 and ubi8/nodejs-16-minimal container images are now fully supported

The ubi8/nodejs-16 and ubi8/nodejs-16-minimal container images, previously available as a Technology Preview, are fully supported with the release of the RHBA-2021:5260 advisory. These container images include Node.js 16.13, which is a Long Term Support (LTS) version.

(BZ#2001020)

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