Chapter 1. Overview

1.1. Major changes in RHEL 9.2

Installer and image creation

Key highlights for image builder:

Image builder on-prem now offers a new and improved way to create blueprints and images in the image builder web console.
Creating customized files and directories in the /etc directory is now supported.
The RHEL for Edge Simplified Installer image type is now available in the image builder web console.

For more information, see New features - Installer and image creation.

RHEL for Edge

Key highlights for RHEL for Edge:

Specifying a user in a blueprint for simplified-installer images is now supported.
The Ignition provisioning utility is now supported in RHEL for Edge Simplified images.
Simplified Installer images can now be composed without the FDO customization section in the blueprint.

For more information, see New features - RHEL for Edge.

Security

Key security-related highlights:

The OpenSSL secure communications library was rebased to version 3.0.7.
SELinux user-space packages were updated to version 3.5.
Keylime was rebased to version 6.5.2
OpenSCAP was rebased to version 1.3.7.
SCAP Security Guide was rebased to version 0.1.66.
A new rule for idle session termination was added to the SCAP Security Guide.
Clevis now accepts external tokens.
Rsyslog TLS-encrypted logging now supports multiple CA files.
Rsyslog privileges are limited to minimize security exposure.
The fapolicyd framework now provides filtering of the RPM database.

See New features - Security for more information.

Dynamic programming languages, web and database servers

Later versions of the following Application Streams are now available:

Python 3.11
nginx 1.22
PostgreSQL 15

The following components have been upgraded:

Git to version 2.39.1
Git LFS to version 3.2.0

See New features - Dynamic programming languages, web and database servers for more information.

Compilers and development tools

Updated system toolchain

The following system toolchain components have been updated in RHEL 9.2:

GCC 11.3.1
glibc 2.34
binutils 2.35.2

Updated performance tools and debuggers

The following performance tools and debuggers have been updated in RHEL 9.2:

GDB 10.2
Valgrind 3.19
SystemTap 4.8
Dyninst 12.1.0
elfutils 0.188

Updated performance monitoring tools

The following performance monitoring tools have been updated in RHEL 9.2:

PCP 6.0.1
Grafana 9.0.9

Updated compiler toolsets

The following compiler toolsets have been updated in RHEL 9.2:

GCC Toolset 12
LLVM Toolset 15.0.7
Rust Toolset 1.66
Go Toolset 1.19.6

For detailed changes, see New features - Compilers and development tools.

Java implementations in RHEL 9

The RHEL 9 AppStream repository includes:

The java-17-openjdk packages, which provide the OpenJDK 17 Java Runtime Environment and the OpenJDK 17 Java Software Development Kit.
The java-11-openjdk packages, which provide the OpenJDK 11 Java Runtime Environment and the OpenJDK 11 Java Software Development Kit.
The java-1.8.0-openjdk packages, which provide the OpenJDK 8 Java Runtime Environment and the OpenJDK 8 Java Software Development Kit.

The Red Hat build of OpenJDK packages share a single set of binaries between its portable Linux releases and RHEL 9.2 and later releases. With this update, there is a change in the process of rebuilding the OpenJDK packages on RHEL from the source RPM. For more information about the new rebuilding process, see the README.md file which is available in the SRPM package of the Red Hat build of OpenJDK and is also installed by the java-*-openjdk-headless packages under the /usr/share/doc tree.

For more information, see OpenJDK documentation.

The web console

The RHEL web console now performs additional steps for binding LUKS-encrypted root volumes to NBDE deployments.

You can also apply the following cryptographic subpolicies through the graphical interface now: DEFAULT:SHA1, LEGACY:AD-SUPPORT, and FIPS:OSPP.

See New features - The web console for more information.

Containers

Notable changes include:

The podman RHEL System Role is now available.
Clients for sigstore signatures with Fulcio and Rekor are now available.
Skopeo now supports generating sigstore key pairs.
Podman now supports events for auditing.
The Container Tools packages have been updated.
The Aardvark and Netavark networks stack now supports custom DNS server selection.
Toolbox is now available.
Podman Quadlet is now available as a Technology Preview.
The CNI network stack has been deprecated.

See New features - Containers for more information.

1.2. In-place upgrade

In-place upgrade from RHEL 8 to RHEL 9

The supported in-place upgrade paths currently are:

From RHEL 8.6 to RHEL 9.0 and RHEL 8.8 to RHEL 9.2 on the following architectures:
- 64-bit Intel
- 64-bit AMD
- 64-bit ARM
- IBM POWER 9 (little endian)
- IBM Z architectures, excluding z13
From RHEL 8.6 to RHEL 9.0 and RHEL 8.8 to RHEL 9.2 on systems with SAP HANA

For more information, see Supported in-place upgrade paths for Red Hat Enterprise Linux.

For instructions on performing an in-place upgrade, see Upgrading from RHEL 8 to RHEL 9.

If you are upgrading to RHEL 9.2 with SAP HANA, ensure that the system is certified for SAP prior to the upgrade. For instructions on performing an in-place upgrade on systems with SAP environments, see How to in-place upgrade SAP environments from RHEL 8 to RHEL 9.

Notable enhancements include:

The RHEL in-place upgrade path strategy has changed. For more information, see Supported in-place upgrade paths for Red Hat Enterprise Linux.
With the release of RHEL 9.2, multiple upgrade paths are now available for the in-place upgrade from RHEL 8 to RHEL 9. For the current release, it is possible to perform an in-place upgrade from either RHEL 8.8 to RHEL 9.2, or RHEL 8.6 to RHEL 9.0.Note that the available upgrade paths differ between standard RHEL systems and RHEL systems with SAP HANA.
The latest release of the leapp-upgrade-el8toel9 package now contains all required leapp data files. Customers no longer need to manually download these data files.
In-place upgrades of RHEL 8.8 systems in FIPS mode are now supported.
In-place upgrades using an ISO image that contains the target version are now possible.
RPM signatures are now automatically checked during the in-place upgrade. To disable the automatic check, use the --nogpgcheck option when performing the upgrade.
Systems that are subscribed to RHSM are now automatically registered with Red Hat Insights. To disable the automatic registration, set the LEAPP_NO_INSIGHTS_REGISTER environment variable to 1.
Red Hat now collects upgrade-related data, such as the upgrade start and end times and whether the upgrade was successful, for utility usage analysis. To disable data collection, set the LEAPP_NO_RHSM_FACTS environment variable to 1.

In-place upgrade from RHEL 7 to RHEL 9

It is not possible to perform an in-place upgrade directly from RHEL 7 to RHEL 9. However, you can perform an in-place upgrade from RHEL 7 to RHEL 8 and then perform a second in-place upgrade to RHEL 9. For more information, see Upgrading from RHEL 7 to RHEL 8.

1.3. Red Hat Customer Portal Labs

Red Hat Customer Portal Labs is a set of tools in a section of the Customer Portal available at https://access.redhat.com/labs/. The applications in Red Hat Customer Portal Labs can help you improve performance, quickly troubleshoot issues, identify security problems, and quickly deploy and configure complex applications. Some of the most popular applications are:

1.4. Additional resources

Capabilities and limits of Red Hat Enterprise Linux 9 as compared to other versions of the system are available in the Knowledgebase article Red Hat Enterprise Linux technology capabilities and limits.

Information regarding the Red Hat Enterprise Linux life cycle is provided in the Red Hat Enterprise Linux Life Cycle document.

The Package manifest document provides a package listing for RHEL 9, including licenses and application compatibility levels.

Application compatibility levels are explained in the Red Hat Enterprise Linux 9: Application Compatibility Guide document.

Major differences between RHEL 8 and RHEL 9, including removed functionality, are documented in Considerations in adopting RHEL 9.

Instructions on how to perform an in-place upgrade from RHEL 8 to RHEL 9 are provided by the document Upgrading from RHEL 8 to RHEL 9.

The Red Hat Insights service, which enables you to proactively identify, examine, and resolve known technical issues, is available with all RHEL subscriptions. For instructions on how to install the Red Hat Insights client and register your system to the service, see the Red Hat Insights Get Started page.