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Red Hat Enterprise Linux

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Not to be confused with Red Hat Linux.
Red Hat Enterprise Linux
Red Hat Enterprise Linux 9.0, showing its desktop environment GNOME 40.
DeveloperRed Hat, Inc.
OS familyLinux (Unix-like)
Working stateCurrent
Source modelOpen source
Initial releaseFebruary 22, 2000; 24 years ago (2000-02-22)[1]
Latest release
9:9.5 / November 13, 2024; 8 days ago (2024-11-13)
8:8.10 / May 22, 2024; 5 months ago (2024-05-22)
7:7.9 / September 29, 2020; 4 years ago (2020-09-29)
Latest preview9 Beta / November 3, 2021; 3 years ago (2021-11-03)[2]
Marketing targetCommercial market (servers, mainframes, supercomputers, workstations)
Available inMultilingual
Update methodSoftware Updater
Package manager
Platformsx86-64; ARM64; IBM Z; IBM Power Systems[4]
Kernel typeMonolithic (Linux)
UserlandGNU
Default
user interface		GNOME Shell, Bash
LicenseVarious free software licenses, plus proprietary binary blobs[5]
Preceded byRed Hat Linux
Official websiteredhat.com/rhel/

Red Hat Enterprise Linux (RHEL) is a commercial open-source[6][7][8] Linux distribution[9][10] developed by Red Hat for the commercial market. Red Hat Enterprise Linux is released in server versions for x86-64, Power ISA, ARM64, and IBM Z and a desktop version for x86-64. Fedora Linux and CentOS Stream serve as its upstream sources. All of Red Hat's official support and training, together with the Red Hat Certification Program, focuses on the Red Hat Enterprise Linux platform.

The first version of Red Hat Enterprise Linux to bear the name originally came onto the market as "Red Hat Linux Advanced Server". In 2003, Red Hat rebranded Red Hat Linux Advanced Server to "Red Hat Enterprise Linux AS"[11] and added two more variants, Red Hat Enterprise Linux ES and Red Hat Enterprise Linux WS.[12]

Red Hat previously used strict trademark rules to restrict free re-distribution of their officially supported versions of Red Hat Enterprise Linux[13] but still freely provided its source code. Third-party derivatives were able to be built and redistributed by stripping away non-free components like Red Hat's trademarks. Examples include community-supported distributions like Rocky Linux and AlmaLinux, and commercial ones like Oracle Linux. In 2023, Red Hat decided to stop making the source code of Red Hat Enterprise Linux available to the public. The code is still available to Red Hat customers, as well as developers using free accounts, though under conditions that forbid redistribution of the source code.[10]

Variants

[edit]

Red Hat Enterprise Linux Server subscription is available at no cost for development purposes.[14] Developers need to register for the Red Hat Developer Program and agree to license terms forbidding production use and redistribution of the source code.[10] This free developer subscription was announced on March 31, 2016.

There are also "Academic" editions of the Desktop and Server variants.[15] They are offered to schools and students, are less expensive, and are provided with Red Hat technical support as an optional extra. Web support based on the number of customer contacts can be purchased separately.

It is often assumed the branding ES, AS, and WS stand for "Entry-level Server",[16][17] "Advanced Server" and "Work Station", respectively. The reason for this is that the ES product is indeed the company's base enterprise server product, while AS is the more advanced product. However, nowhere on its site or in its literature does Red Hat say what AS, ES, and WS stand for.

In Red Hat Enterprise Linux 5 there are new editions that substitute former Red Hat Enterprise Linux AS/ES/WS/Desktop:[18][19]

  • Red Hat Enterprise Linux Advanced Platform (former AS)
  • Red Hat Enterprise Linux (former ES) (limited to two CPUs)
  • Red Hat Enterprise Linux Desktop with Workstation and Multi-OS option
  • Red Hat Enterprise Linux Desktop with Workstation option (former WS)
  • Red Hat Enterprise Linux Desktop with Multi-OS option
  • Red Hat Enterprise Linux Desktop (former Desktop)

Red Hat had also announced its Red Hat Global Desktop Linux edition "for emerging markets".[20]

RHEL 4, 3, and prior releases had four variants:

  • Red Hat Enterprise Linux AS for mission-critical/enterprise computer systems.
  • Red Hat Enterprise Linux ES for supported network servers
  • Red Hat Enterprise Linux WS for technical power user enterprise desktops for high-performance computing
  • Red Hat Desktop for multiple deployments of single-user desktops for enterprises.

Relationship with Fedora Linux

[edit]

The Fedora Project provides the following explanation:[21]

Fedora is a free distribution and community project and upstream for Red Hat Enterprise Linux. Fedora is a general purpose system that gives Red Hat and the rest of its contributor community the chance to innovate rapidly with new technologies. Red Hat Enterprise Linux is a commercial enterprise operating system and has its own set of test phases including alpha and beta releases which are separate and distinct from Fedora development.

Originally, Red Hat sold boxed versions of Red Hat Linux directly to consumers and business through phone support. The Fedora Project began in 2002 as a set of community supported packages for Red Hat Linux. However, the six month release cycle of Red Hat Linux was too disruptive for business users and Red Hat wanted a more reliable revenue stream. In 2002 Red Hat began releasing Red Hat Enterprise Linux based on Red Hat Linux, but with a much more conservative release cycle and a subscription based support program. A year later, Red Hat discontinued the Red Hat Linux product line, merging it with the Fedora community packages and releasing the resulting Fedora distribution for free.[22]

Fedora now serves as upstream for future versions of RHEL: RHEL trees are forked off the Fedora repository, and released after a substantial stabilization and quality assurance effort.[23][needs update?] RHEL source code is also not freely available, as those that obtain it are forbidden from redistribution.[10] For example, RHEL 5 was forked from Fedora at the end of 2006 (approximately at the time of the Fedora Core 6 release) and released more or less together with Fedora 14. By the time RHEL 6 was released, many features from Fedora 13 and 14 had already been backported into it. The Fedora Project lists the following lineages for older Red Hat Enterprise releases:[23]

  • Red Hat Linux 6.2/7 to Red Hat Linux Enterprise Edition 6.2E
  • Red Hat Linux 7.2, 7.2A to Red Hat Enterprise Linux 2.1
  • Red Hat Linux 9 to Red Hat Enterprise Linux 3
  • Fedora Core 3 to Red Hat Enterprise Linux 4
  • Fedora Core 6 to Red Hat Enterprise Linux 5
  • Fedora 12, 13 to Red Hat Enterprise Linux 6
  • Fedora 19, 20 to Red Hat Enterprise Linux 7
  • Fedora 28 to CentOS Stream 8 to Red Hat Enterprise Linux 8[24]
  • Fedora 34 to CentOS Stream 9 to Red Hat Enterprise Linux 9[25]

In addition, the Fedora project publishes a set of packages for RHEL called the Extra Packages for Enterprise Linux (EPEL). EPEL packages can be expected to work in RHEL, but it is up to willing community members to maintain the packages and back port any upstream changes. As such, packages "may come and go" during the ten-year lifespan of the RHEL release and Red Hat support plans do not include resolving issues caused by EPEL packages.[26]

Derivatives

[edit]
Main article: Red Hat Enterprise Linux derivatives

Originally, Red Hat's enterprise product, then known as Red Hat Linux, was made freely available to anybody who wished to download it, while Red Hat made money from support. Red Hat then moved towards splitting its product line into Red Hat Enterprise Linux which was designed to be stable and with long-term support for enterprise users and Fedora as the community distribution and project sponsored by Red Hat. The use of trademarks prevents verbatim copying of Red Hat Enterprise Linux.

Red Hat Enterprise Linux is derived completely from free and open source software. Until 2023, Red Hat made the source code to its enterprise distribution publicly available through its FTP website. Accordingly, several groups used the source code to compile their own derivatives, typically with changes including the removal of any references to Red Hat's trademarks and pointing the update systems to non-Red Hat servers. Groups which have undertaken this include AlmaLinux, CentOS, MIRACLE LINUX, Oracle Linux, CloudLinux OS, Rocky Linux, Scientific Linux, StartCom Enterprise Linux, Pie Box Enterprise Linux, X/OS, Lineox, and Bull's XBAS for high-performance computing.[27] However, as of June 2023, Red Hat no longer makes the source code freely available; while they still provide the source code to customers and developers.[10] The GNU GPL forbids terms and conditions that prevent users from redistributing the source code of GPL-licensed software, including but not limited to the GNU core utilities (such as cat, ls, and rm), which is licensed under the GNU GPLv3 or later as of version 6.10, and the Linux kernel itself (licensed under the GPLv2 only).[28][29][30] This led to AlmaLinux, one of the RHEL derivative Linux distributions, moving away from "1:1 bug for bug" compatibility to "application binary interface (ABI) compatible", while Oracle, SUSE, and CIQ (the company behind Rocky Linux) collaborated to form the Open Enterprise Linux Association (OpenELA) in order to provide "open and free Enterprise Linux (EL) source code".[31][32]

Derivatives of Red Hat Enterprise Linux are free but do not get any commercial support or consulting services from Red Hat and lack software, hardware or security certifications from Red Hat. They also do not get access to Red Hat services like Red Hat Network.

Unusually, Red Hat took steps to obfuscate their changes to the Linux kernel for RHEL 6.0 by not publicly providing the patch files for their changes in the source tarball, and only releasing the finished product in source form. Speculation suggested that the move was made to affect Oracle's competing rebuild and support services, which further modifies the distribution. This practice however, still complies with the GNU GPL since source code is defined as "[the] preferred form of the work for making modifications to it", and the distribution still complies with this definition.[33] Red Hat's CTO Brian Stevens later confirmed the change, stating that certain information (such as patch information) would now only be provided to paying customers to make the Red Hat product more competitive against the growing number of companies offering support for products based on RHEL. CentOS developers had no objections to the change since they do not make any changes to the kernel beyond what is provided by Red Hat.[34] Their competitor Oracle announced in November 2012 that they were releasing a RedPatch service, which allows public view of the RHEL kernel changes, broken down by patch.[35][36]

[edit]
See also: Commercial products based on Red Hat Enterprise Linux

A number of commercial vendors use Red Hat Enterprise Linux as a base for the operating system in their products. Two of the best known are the Console Operating System in VMware ESX Server and Oracle Linux.

Version history and timeline[37]

[edit]

Naming convention

[edit]

Each release is given a codename which is selected by a vote of the developers. The codenames don't have a specific pattern (unlike Ubuntu or Debian).

RHEL 9

[edit]

Red Hat Enterprise Linux 9 was announced at Red Hat Summit on May 10, 2022, and was officially released on May 17, 2022 (2022-05-17).[38] In this version of the system introduced a Linux Kernel 5.14.0 and Gnome 40.

RHEL 9 was the first to be based on CentOS Stream, itself based on Fedora Linux, while historically RHEL was based directly on Fedora Linux.[39]

The first beta for Red Hat Enterprise Linux 9 (Plow), based on Fedora Linux 34, was released on November 3, 2021.[2]

Red Hat Enterprise Linux 9 (Plow) was released on May 18, 2022.[40] The name Plow was the Appalachian Trail nickname for Tim Burke, one of the founders of RHEL and retired leader of RHEL engineering.[41]

  • Red Hat Enterprise Linux 9.0, May 17, 2022; 2 years ago (2022-05-17), uses Linux kernel 5.14.0-70.13.1.el9_0
    • 9.1, November 15, 2022; 2 years ago (2022-11-15)
      • kernel 5.14.0-162.6.1.el9_1
    • 9.2, May 10, 2023; 18 months ago (2023-05-10)
      • kernel 5.14.0-284.11.1.el9_2
    • 9.3, November 7, 2023; 12 months ago (2023-11-07)
      • kernel 5.14.0-362.8.1.el9_3
    • 9.4, April 30, 2024; 6 months ago (2024-04-30)
      • kernel 5.14.0-427.13.1.el9_4
    • 9.5, November 13, 2024; 8 days ago (2024-11-13)
      • kernel 5.14.0-503.11.1.el9_5

RHEL 8

[edit]

Red Hat Enterprise Linux 8 (Ootpa) is based on Fedora 28, upstream Linux kernel 4.18, GCC 8.2, glibc 2.28, systemd 239, GNOME 3.28, and the switch to Wayland. The first beta was announced on November 14, 2018.[42] Red Hat Enterprise Linux 8 was officially released on May 7, 2019 (2019-05-07).[43]

With Release 8 of Red Hat Enterprise Linux, IBM has completed transition of POWER8 and POWER9 servers to little-endian mode.[44][45][46]

The name Ootpa was a tribute to Larry Troan. His son, Eric Troan was Red Hat's first head engineer and his username was ewt, so his father was given the name ewt's pa, pronounced Ootpa.[41]

  • Red Hat Enterprise Linux 8.0, May 7, 2019; 5 years ago (2019-05-07), uses Linux kernel 4.18.0-80[43]
    • 8.1, November 5, 2019; 5 years ago (2019-11-05), uses Linux kernel 4.18.0-147[47]
      • GNOME rebased to 3.32
    • 8.2, April 28, 2020; 4 years ago (2020-04-28)
      • kernel 4.18.0-193
    • 8.3, November 3, 2020; 4 years ago (2020-11-03)
      • kernel 4.18.0-240
    • 8.4, May 18, 2021; 3 years ago (2021-05-18) [48]
      • kernel 4.18.0-305
    • 8.5, November 9, 2021; 3 years ago (2021-11-09)
      • kernel 4.18.0-348
    • 8.6, May 10, 2022; 2 years ago (2022-05-10)
      • kernel 4.18.0-372.9.1
    • 8.7, November 9, 2022; 2 years ago (2022-11-09)
      • kernel 4.18.0-425.3.1
    • 8.8, May 16, 2023; 18 months ago (2023-05-16)
      • kernel 4.18.0-477.10.1.el8_8
    • 8.9, November 14, 2023; 12 months ago (2023-11-14)
      • kernel 4.18.0-513.5.1.el8_9
    • 8.10, May 22, 2024; 5 months ago (2024-05-22)
      • kernel 4.18.0-553.el8_10

RHEL 7

[edit]

Red Hat Enterprise Linux 7 (Maipo) is based on Fedora 18 and Fedora 19, upstream Linux kernel 3.10, systemd 208 (updated to 219 in RHEL 7.2), and GNOME 3.8 (rebased to GNOME 3.28 in RHEL 7.6) The first beta was announced on 11 December 2013,[49][50] and a release candidate was made available on 15 April 2014.[51] On June 10, 2014 (2014-06-10) Red Hat Enterprise Linux 7 was officially released.[52]

  • Red Hat Enterprise Linux 7.0 (Maipo), June 9, 2014; 10 years ago (2014-06-09), uses Linux kernel 3.10.0-123
    • 7.1, March 5, 2015; 9 years ago (2015-03-05)[53]
      • kernel 3.10.0-229
    • 7.2, November 19, 2015; 9 years ago (2015-11-19)[54]
      • kernel 3.10.0-327
      • systemd updated to 219
      • Fedora rebased to 21
      • GNOME rebased to 3.14
    • 7.3, November 3, 2016; 8 years ago (2016-11-03)[55]
      • kernel 3.10.0-514
    • 7.4, July 18, 2017; 7 years ago (2017-07-18)[56]
      • kernel 3.10.0-693
      • Fedora rebased to 25
      • GNOME rebased to 3.22
    • 7.5, April 10, 2018; 6 years ago (2018-04-10)[57]
      • kernel 3.10.0-862
      • Fedora rebased to 27
      • GNOME rebased to 3.26[58]
    • 7.6, October 30, 2018; 6 years ago (2018-10-30)[59]
      • kernel 3.10.0-957
      • Fedora rebased to 28
      • GNOME rebased to 3.28
    • 7.7, August 6, 2019; 5 years ago (2019-08-06)[60]
      • kernel 3.10.0-1062
      • GNOME remains as 3.28
    • 7.8, March 31, 2020; 4 years ago (2020-03-31)[61]
      • kernel 3.10.0-1127
      • GNOME remains as 3.28
    • 7.9, September 29, 2020; 4 years ago (2020-09-29)[62]
      • kernel 3.10.0-1160
    • 7, Extended Life-cycle Support (ELS) Start Date July 1, 2024; 4 months ago (2024-07-01)
      • aka added ELS entitlement until ELS end Date June 30, 2028; 3 years' time (2028-06-30)[63]

RHEL 6

[edit]

Red Hat Enterprise Linux 6 was forked from Fedora 10 and contains many backported features from Fedora 11 and Fedora 12.

  • Red Hat Enterprise Linux 6 (Santiago), November 9, 2010; 14 years ago (2010-11-09), uses Linux kernel 2.6.32-71[64]
    • 6.1, May 19, 2011; 13 years ago (2011-05-19) (kernel 2.6.32-131.0.15)
    • 6.2, December 6, 2011; 12 years ago (2011-12-06) (kernel 2.6.32-220)
    • 6.3, June 20, 2012; 12 years ago (2012-06-20) (kernel 2.6.32-279)
    • 6.4, February 21, 2013; 11 years ago (2013-02-21) (kernel 2.6.32-358)
    • 6.5, November 21, 2013; 11 years ago (2013-11-21) (kernel 2.6.32-431)
    • 6.6, October 14, 2014; 10 years ago (2014-10-14) (kernel 2.6.32-504)
    • 6.7, July 22, 2015; 9 years ago (2015-07-22) (kernel 2.6.32-573)
    • 6.8, May 10, 2016; 8 years ago (2016-05-10) (kernel 2.6.32-642)
    • 6.9, March 21, 2017; 7 years ago (2017-03-21) (kernel 2.6.32-696)
    • 6.10, June 19, 2018; 6 years ago (2018-06-19) (kernel 2.6.32-754)
    • 6 ELS +, Extended Life-cycle Support (ELS) Start Date November 30, 2020; 3 years ago (2020-11-30)
      • aka added ELS entitlement until ELS end Date June 30, 2024; 4 months ago (2024-06-30)

RHEL 5

[edit]

Red Hat Enterprise Linux 5 has forked with Fedora Core 6.

  • Red Hat Enterprise Linux 5 (Tikanga), March 15, 2007; 17 years ago (2007-03-15), uses Linux kernel 2.6.18-8
    • 5.1, November 7, 2007; 17 years ago (2007-11-07) (kernel 2.6.18-53)
    • 5.2, May 21, 2008; 16 years ago (2008-05-21) (kernel 2.6.18-92)
    • 5.3, January 20, 2009; 15 years ago (2009-01-20) (kernel 2.6.18-128)
    • 5.4, September 2, 2009; 15 years ago (2009-09-02) (kernel 2.6.18-164)
    • 5.5, March 30, 2010; 14 years ago (2010-03-30) (kernel 2.6.18-194)
    • 5.6, January 13, 2011; 13 years ago (2011-01-13) (kernel 2.6.18-238)
    • 5.7, July 21, 2011; 13 years ago (2011-07-21) (kernel 2.6.18-274)
    • 5.8, February 20, 2012; 12 years ago (2012-02-20) (kernel 2.6.18-308)
    • 5.9, January 7, 2013; 11 years ago (2013-01-07) (kernel 2.6.18-348)
    • 5.10, October 1, 2013; 11 years ago (2013-10-01) (kernel 2.6.18-371)
    • 5.11, September 16, 2014; 10 years ago (2014-09-16) (kernel 2.6.18-398)
    • 5.11+, Extended Life-cycle Support (ELS) Start Date March 31, 2017; 7 years ago (2017-03-31)
      • aka added ELS entitlement until ELS end Date November 30, 2020; 3 years ago (2020-11-30)

RHEL 4

[edit]

RHEL 4 introduced Linux kernel 2.6 versions and extended attributes on ext2 and ext3 file systems.[65]

  • Red Hat Enterprise Linux 4 (Nahant), February 15, 2005; 19 years ago (2005-02-15), uses Linux kernel 2.6.9-5
    • Update 1, June 8, 2005; 19 years ago (2005-06-08) (kernel 2.6.9-11)
    • Update 2, October 5, 2005; 19 years ago (2005-10-05) (kernel 2.6.9-22)
    • Update 3, March 12, 2006; 18 years ago (2006-03-12) (kernel 2.6.9-34)
    • Update 4, August 10, 2006; 18 years ago (2006-08-10) (kernel 2.6.9-42)
    • Update 5, May 1, 2007; 17 years ago (2007-05-01) (kernel 2.6.9-55)
    • Update 6, November 15, 2007; 17 years ago (2007-11-15) (kernel 2.6.9-67)
    • Update 7, July 29, 2008; 16 years ago (2008-07-29) (kernel 2.6.9-78)
    • Update 8, May 19, 2009; 15 years ago (2009-05-19) (kernel 2.6.9-89)
    • Update 9, February 16, 2011; 13 years ago (2011-02-16) (kernel 2.6.9-100)

RHEL 3

[edit]
  • Red Hat Enterprise Linux 3 (Taroon), October 22, 2003; 21 years ago (2003-10-22), uses Linux kernel 2.4.21-4
    • Update 1, January 16, 2004; 20 years ago (2004-01-16) (kernel 2.4.21-9)
    • Update 2, May 12, 2004; 20 years ago (2004-05-12) (kernel 2.4.21-15)
    • Update 3, September 3, 2004; 20 years ago (2004-09-03) (kernel 2.4.21-20)
    • Update 4, December 12, 2004; 19 years ago (2004-12-12) (kernel 2.4.21-27)
    • Update 5, May 18, 2005; 19 years ago (2005-05-18) (kernel 2.4.21-32)
    • Update 6, September 28, 2005; 19 years ago (2005-09-28) (kernel 2.4.21-37)
    • Update 7, March 17, 2006; 18 years ago (2006-03-17) (kernel 2.4.21-40)
    • Update 8, July 20, 2006; 18 years ago (2006-07-20) (kernel 2.4.21-47)
    • Update 9, June 20, 2007; 17 years ago (2007-06-20) (kernel 2.4.21-50)

RHEL 2.1

[edit]
  • Red Hat Enterprise Linux 2.1 AS (Pensacola), March 23, 2002; 22 years ago (2002-03-23), uses Linux kernel 2.4.9-e.3
    • Update 1, February 14, 2003; 21 years ago (2003-02-14) (kernel 2.4.9-e.12)
    • Update 2, March 29, 2003; 21 years ago (2003-03-29) (kernel 2.4.9-e.24)
    • Update 3, December 19, 2003; 20 years ago (2003-12-19) (kernel 2.4.9-e.34)
    • Update 4, April 21, 2004; 20 years ago (2004-04-21) (kernel 2.4.9-e.40)
    • Update 5, August 18, 2004; 20 years ago (2004-08-18) (kernel 2.4.9-e.49)
    • Update 6, December 13, 2004; 19 years ago (2004-12-13) (kernel 2.4.9-e.57)
    • Update 7, April 28, 2005; 19 years ago (2005-04-28)[66]
  • Red Hat Enterprise Linux 2.1 ES (Panama), May 2003[citation needed]

Product life cycle

[edit]

The life cycle of Red Hat Enterprise Linux is at least seven years for versions 3 and 4, and spans at least 10 years for versions 5, 6, 7, 8 and 9. The life cycle comprises several phases of varying length with different degrees of support. During the first phase ("Production 1"), Red Hat provides full support and updates software and hardware drivers. In later phases ("Production 2" and "Production 3"), only security and other important fixes are provided and support for new hardware is gradually reduced.[67]

In the last years of the support lifecycle (after seven years for version 4 and earlier, and after 10 years for version 5 and later), critical and security-related fixes are only provided to customers who pay an additional subscription ("Extended Lifecycle Support Add-On") that is available for versions 3, 4, 5 and 6. This covers a limited number of packages.[68] Red Hat only supports major version upgrades from version 6 to version 7 and from version 7 to version 8.[69]

RHEL
version		 Last minor
release		 Release date End of Full Support End of Maintenance
Support 1 (RHEL 5, 6, 7)		 End of
Maintenance Support (RHEL 8, 9),
Maintenance Support 2 (RHEL 5, 6, 7)
(product retirement)		 End of Extended
Lifecycle Support
Old version, no longer maintained: 2.1 U-7 26 March 2002 (AS)
1 May 2003 (ES) 		30 November 2004 31 May 2005 31 May 2009[70] —
Old version, no longer maintained: 3 U-9 23 October 2003 20 July 2006 30 June 2007 31 October 2010[71] 30 January 2014
Old version, no longer maintained: 4 U-9 14 February 2005 31 March 2009 16 February 2011 29 February 2012 31 March 2017
Old version, no longer maintained: 5 5.11 15 March 2007 8 January 2013 31 January 2014 31 March 2017 30 November 2020
Old version, no longer maintained: 6 6.10 10 November 2010 10 May 2016 10 May 2017 30 November 2020 30 June 2024
Old version, yet still maintained: 7 7.9 10 June 2014[72] 6 August 2019 6 August 2020 30 June 2024 30 June 2028[73]
Old version, yet still maintained: 8 8.10 7 May 2019 May 2024 — May 2029 31 May 2031[74]
Current stable version: 9 9.5 08 Nov 2022 May 2027 — May 2032 31 May 2034[74]
Legend:
Old version, not maintained
Old version, still maintained
Latest version
Latest preview version
Future release

Kernel backporting

[edit]

To maintain a stable application binary interface (ABI), Red Hat does not update the kernel version, but instead backports new features to the same kernel version with which a particular version of RHEL has been released. New features are backported throughout the Production 1 phase of the RHEL lifecycle.[75] Consequently, RHEL may use a Linux kernel with a dated version number, yet the kernel is up-to-date regarding not only security fixes, but also certain features.[76] One specific example is the SO_REUSEPORT socket option which was added to Linux kernel 3.9, and was subsequently backported and became available since RHEL 6.5, which uses version 2.6.32 of the Linux kernel.[77][78][79]

Extended Update Support (EUS) / Z Tree

[edit]

The Extended Update Support (EUS) allows an organization / company to choose when they change to a new minor version. For the first 6 months of the EUS channel / yum repo, features may be added, but then the channel is locked down so that only bug and security fixes are patched. The organization / company then has 24 months to move to a new EUS branch. EUS allows the organization / company to stay on a minor version if required by a third-party application which is only tested with a particular minor version of RHEL, such as Oracle Database, IBM Db2, IBM Cloud Orchestrator, Hortonworks. There may also be extra costs associated with using the EUS repos/channels depending on the agreement the organization / company has with Red Hat.[80] For more information on what is Included/Excluded from the EUS see.[80]

Note

[edit]
  • The EUS update mechanism for using older minor version branches is not available to CentOS, Oracle Linux and Scientific Linux, as Red Hat do not publish source packages for rebuilding.[81] As such, projects clearly state to ensure users run on the latest available minor version within a supported major release.

Updates

[edit]

In general one can move from z streams to the next version of the z stream.

  • The 7.4.z EUS channel after the release of 7.4.
  • The 7.5.z EUS channel after the release of 7.5.

Any 7.y.z EUS channel where y is greater than 1. The standard base channel for Red Hat Enterprise Linux 7, which is the most recent minor release aka rhel 7Y where y is the latest greatest.

One can not go back in time, aka 7.5.z to 7.4.z and will NOT be supported.[80]

RHEL 6

[edit]

Red Hat Enterprise Linux 6 was forked from Fedora 12 and contains many backported features from Fedora 13 and 14.

  • Red Hat Enterprise Linux 6 (Santiago), 10 November 2010, uses Linux kernel 2.6.32-71[37]
    • 6.7, also termed Update 7, July 22, 2015; 9 years ago (2015-07-22) (kernel 2.6.32-573)
      • 1st Day of EUS Window July 22, 2015; 9 years ago (2015-07-22)
      • Last Day of EUS Window July 31, 2017; 7 years ago (2017-07-31)
    • Note: There were no more EUS for Rhel6 after 6.7

RHEL 7

[edit]

Red Hat Enterprise Linux 7 (Maipo) is based on Fedora 19, upstream Linux kernel 3.10, 10 June 2014, uses Linux kernel 3.10.0-123[37]

  • 7.1, also termed Update 1, March 5, 2015; 9 years ago (2015-03-05) (kernel 3.10.0-229)[53]
    • 1st Day of EUS Window March 5, 2015; 9 years ago (2015-03-05)
    • Last Day of EUS Window March 31, 2017; 7 years ago (2017-03-31)
  • 7.2, also termed Update 2, November 19, 2015; 9 years ago (2015-11-19) (kernel 3.10.0-327)[54]
    • 1st Day of EUS Window November 19, 2015; 9 years ago (2015-11-19)
    • Last Day of EUS Window November 30, 2017; 6 years ago (2017-11-30)
  • 7.3, also termed Update 3, November 3, 2016; 8 years ago (2016-11-03) (kernel 3.10.0-514)[55]
    • 1st Day of EUS Window November 3, 2016; 8 years ago (2016-11-03)
    • Last Day of EUS Window November 30, 2018; 5 years ago (2018-11-30)
    • Features may be updated[82]
  • 7.4, also termed Update 4, August 1, 2017; 7 years ago (2017-08-01) (kernel 3.10.0-693)[56]
    • 1st Day of EUS Window August 1, 2017; 7 years ago (2017-08-01)
    • Last Day of EUS Window August 31, 2019; 5 years ago (2019-08-31)
  • 7.5, also termed Update 5, April 10, 2018; 6 years ago (2018-04-10) (kernel 3.10.0-862)[57]
    • 1st Day of EUS Window April 10, 2018; 6 years ago (2018-04-10)
    • Last Day of EUS Window April 30, 2020; 4 years ago (2020-04-30)
  • 7.6, also termed Update 6, October 30, 2018; 6 years ago (2018-10-30) (kernel 3.10.0-957)[59][83]
    • 1st Day of EUS Window October 30, 2018; 6 years ago (2018-10-30)
    • Last Day of EUS Window May 31, 2021; 3 years ago (2021-05-31)
  • 7.7, also termed Update 7, August 6, 2019; 5 years ago (2019-08-06) (kernel 3.10.0-1062)[60][83]
    • 1st Day of EUS Window August 6, 2019; 5 years ago (2019-08-06)
    • Last Day of EUS Window August 30, 2021; 3 years ago (2021-08-30)
  • 7.8, also termed Update 8[84]
    • Released on March 31, 2020; 4 years ago (2020-03-31)
  • 7.9, also termed Update 9 is the final RHEL 7 release[83][85]
    • Released on September 30, 2020; 4 years ago (2020-09-30)

RHEL 8

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Red Hat Enterprise Linux 8 (Ootpa) is based on Fedora 28, upstream Linux kernel 4.18, systemd 239, and GNOME 3.28. The first beta was announced on 14 November 2018.[42] Red Hat Enterprise Linux 8 was officially released on 2019-05-07 (2019-05-07).[43]

For RHEL 8, the update schedule is approximately:[86]

  • 8.0 - 6 Month Minor Release (kernel 4.18.0-80)[87]
    • 1st Day of Support Window May 7, 2019; 5 years ago (2019-05-07)[87]
  • 8.1 - 6 Month Minor Release with Extended Support and Update Services for SAP Solutions (kernel 4.18.0-147)[87]
    • 1st Day of Support Window November 5, 2019; 5 years ago (2019-11-05)[87]
  • 8.2 - 6 Month Minor Release with Extended Support and Update Services for SAP Solutions (kernel 4.18.0-193)[87]
    • 1st Day of Support Window April 28, 2020; 4 years ago (2020-04-28)[87]
  • 8.3 - 6 Month Minor Release (kernel 4.18.0-240)[87]
    • 1st Day of Support Window November 3, 2020; 4 years ago (2020-11-03)[87]
  • 8.4 - 6 Month Minor Release with Extended Support and Update Services for SAP Solutions (kernel 4.18.0-305)[87]
    • 1st Day of Support Window May 18, 2021; 3 years ago (2021-05-18)[87]
  • 8.5 - 6 Month Minor Release (kernel 4.18.0-348)[87]
    • 1st Day of Support Window November 9, 2021; 3 years ago (2021-11-09)[87]
  • 8.6 - 6 Month Minor Release with Extended Support and Update Services for SAP Solutions (kernel 4.18.0-372.9.1)[87]
    • 1st Day of Support Window May 10, 2022; 2 years ago (2022-05-10)[87]
  • 8.7 - 6 Month Minor Release (kernel 4.18.0-425.3.1)[87]
    • 1st Day of Support Window November 9, 2022; 2 years ago (2022-11-09)[87]
  • 8.8 - 6 Month Minor Release with Extended Support and Update Services for SAP Solutions (kernel 4.18.0-477.10.1.el8_8)[87]
    • 1st Day of Support Window May 16, 2023; 18 months ago (2023-05-16)[87]

RHEL 8 application streams

[edit]

In addition to normal OS updates, RHEL 8 also maintains application streams to allow for certain applications to be supported and updated independent of the base OS and to match the maintenance stream of the application vendor.[88] Each application stream will be supported from two to five years with new versions only available during the Red Hat Enterprise Linux Full Support Phase.[89] These apps should be expected to be updated frequently with shorter lifecycles than the base OS packages.

Packages currently offered as streams[89]

  • authd 1.4.4 (through May 2021)
  • container-tools 1 (through May 2021)
  • dotnet 2.1 (through Aug 2021)
  • git 2.18 (through May 2021)
  • httpd 2.4 (through May 2024)
  • Identity Management DL1 (through May 2024)
  • mariadb 10.3 (through May 2023)
  • maven 3.5 (through May 2022)
  • mercurial 4.8 (through May 2022)
  • mysql 8 (through Apr 2023)
  • nginx 1.14 (through May 2021)
  • nodejs 10 (through Apr 2021)
  • openjdk 1.8.0 (through Jun 2023)
  • openjdk 11 (through Oct 2024)
  • perl 5.24 (through May 2021)
  • php 7.2 (through May 2021)
  • postgresql 10 (through May 2024)
  • postgresql 9.6 (through Nov 2021)
  • python 2.7 (through Jun 2024)
  • redis 5 (through May 2022)
  • ruby 2.5 (through Feb 2021)
  • scala 2.1 (through May 2022)
  • swig 3 (through May 2022)
  • varnish 6 (through May 2022)

RHEL 9

[edit]

Red Hat Enterprise Linux 9 (RHEL 9) is a commercial open-source operating system developed by Red Hat for enterprise environments. It is built from the open-source Fedora distribution and aims to provide a stable, secure, and enterprise-grade platform. RHEL 9, released in May 2022, introduces several new features and improvements, especially tailored for cloud-native development, security, automation, and performance enhancements .

Key Features

[edit]
  1. Kernel and Performance RHEL 9 is based on the Linux kernel 5.14, offering improved performance and hardware support. It also features enhanced performance tuning tools for administrators to optimize workloads on modern architectures .
  2. Security Enhancements RHEL 9 includes advanced security measures such as the Integrity Measurement Architecture (IMA), which ensures system integrity . It also incorporates OpenSSL 3.0 for updated cryptography and enhanced security policies . By default, SSH root password login is disabled to encourage the use of key-based authentication. SELinux continues to play a crucial role in enforcing strict security policies .
  3. Automation and Management The integration with Ansible allows for more streamlined automation and configuration management across systems . The Cockpit web console has also been improved, offering new features for managing containers, networking, and storage .
  4. Cloud and Container Support RHEL 9 is designed for cloud-native environments, with strong support for containers and hybrid cloud infrastructures . It is optimized to work seamlessly with Red Hat OpenShift, a Kubernetes-based platform, and supports containerization through tools like Podman. It also includes AppStreams, which provide curated packages for developers, ensuring access to the latest runtimes and frameworks .
  5. Networking and Storage Enhanced NetworkManager features and support for NVMe over Fabrics improve performance and scalability for modern networking and storage configurations .

Use Cases

[edit]

RHEL 9 is suitable for a wide range of enterprise applications across industries such as financial services, healthcare, and government. It is used in both on-premises and cloud environments, with strong support for multi-cloud and hybrid cloud deployments

Support Lifecycle

[edit]

RHEL 9 follows Red Hat's 10-year support lifecycle, which includes full support for the first five years, followed by maintenance support for the remaining five years .

See also

[edit]

References

[edit]
  1. ^ "Red Hat Enterprise Edition Product Line Optimizes Solutions for Top e-Business Applications" (Press release). Red Hat. February 22, 2000. Retrieved February 20, 2020.
  2. ^ a b Cattelain, Gil; Brockmeier, Joe (2021-11-03). "What's new in Red Hat Enterprise Linux 9 Beta". Red Hat. Retrieved 2021-11-03.
  3. ^ Matteson, Scott (2019-03-30). "What's new with Red Hat Enterprise Linux 8 and Red Hat Virtualization". TechRepublic. Retrieved 2019-09-24.
  4. ^ "9.0 Release Notes - Chapter 2. Architectures". Red Hat Customer Portal. Red Hat. Retrieved 2022-12-26.
  5. ^ "Explaining Why We Don't Endorse Other Systems". the Free Software Foundation. Retrieved March 13, 2011.
  6. ^ "Why choose Red Hat for Linux?". www.redhat.com. Archived from the original on 2023-12-31. Retrieved 2024-01-01.
  7. ^ Lardinois, Frederic (2023-07-11). "Why SUSE is forking Red Hat Enterprise Linux". TechCrunch. Archived from the original on 2024-01-01. Retrieved 2024-01-01.
  8. ^ Dickens, Steven (2023-08-16). "The Future Of Open-Source Enterprise Linux And Community Collaboration". Forbes. Archived from the original on 2024-01-01. Retrieved 2024-01-01.
  9. ^ Bradley M., Kuhn. "A Comprehensive Analysis of the GPL Issues With the Red Hat Enterprise Linux (RHEL) Business Model". Software Freedom Conservancy. Retrieved 25 June 2023.
  10. ^ a b c d e Proven, Liam (23 June 2023). "Red Hat strikes a crushing blow against RHEL downstreams". The Register. Retrieved 24 June 2023.
  11. ^ "redhat.com | Red Hat Enterprise Linux". 2003-04-07. Archived from the original on 2003-04-07. Retrieved 2024-06-05.
  12. ^ Azhar, Arslan. "Red Hat Enterprise Linux". {{cite journal}}: Cite journal requires |journal= (help)
  13. ^ "ESR: "We Don't Need the GPL Anymore"". onlamp.com. Archived from the original on 2018-04-17. Retrieved 2008-03-04.
  14. ^ "Downloads: Red Hat Developers". Red Hat. 9 April 2018.
  15. ^ "Enterprise Linux Academic Subscriptions". Red Hat.
  16. ^ "redhat.com | ES". 2003-04-16. Archived from the original on 2003-04-16. Retrieved 2024-06-05.
  17. ^ "redhat.com | Enterprise Linux". 2006-03-15. Archived from the original on 2006-03-15. Retrieved 2024-06-05.
  18. ^ "Moving to Red Hat Enterprise Linux 5". Red Hat. Archived from the original on October 8, 2009. Retrieved 2009-12-02.
  19. ^ "Red Hat Enterprise Linux Server Version Comparison Chart". Red Hat. Archived from the original on 2010-01-05.
  20. ^ "Red Hat Global Desktop Linux: The Best Kept Secret?". linuxtoday.com. Archived from the original on 2007-10-14. Retrieved 2007-08-05.
  21. ^ "Fedora project wiki, the difference between Fedora Linux and RHEL". fedoraproject.org. Retrieved 2010-05-23.
  22. ^ "Fedora project wiki, History of Red Hat Linux". fedoraproject.org. Retrieved 2010-05-23.
  23. ^ a b "Fedora project wiki, Red Hat Enterprise Linux History". fedoraproject.org. Retrieved 2010-06-08.
  24. ^ "Red Hat Enterprise Linux Release Dates". Red Hat Customer Portal. Retrieved 2019-06-17.
  25. ^ "Red Hat Enterprise Linux 9 is now available". Red Hat Customer Portal. 25 October 2021. Retrieved 2022-04-04.
  26. ^ "What's EPEL, and how do I use it?". Red Hat Blog. November 21, 2019.
  27. ^ "SLURM at CEA" (PDF). Archived from the original (PDF) on 2013-05-24. Retrieved 2011-03-21.
  28. ^ "GNU General Public License v3.0". Free Software Foundation, Inc. June 29, 2007. Retrieved August 31, 2023. You may make, run and propagate covered works that you do not convey, without conditions so long as your license otherwise remains in force.
  29. ^ "GNU General Public License v3.0". Free Software Foundation, Inc. June 29, 2007. Retrieved August 31, 2023. You may convey verbatim copies of the Program's source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice; keep intact all notices stating that this License and any non-permissive terms added in accord with section 7 apply to the code; keep intact all notices of the absence of any warranty; and give all recipients a copy of this License along with the Program.
  30. ^ "GNU General Public License v3.0". Free Software Foundation, Inc. June 29, 2007. Retrieved August 31, 2023. You may not impose any further restrictions on the exercise of the rights granted or affirmed under this License. For example, you may not impose a license fee, royalty, or other charge for exercise of rights granted under this License...
  31. ^ "CIQ, Oracle and SUSE Create Open Enterprise Linux..." www.suse.com. SUSE. Retrieved 2023-08-31.
  32. ^ "CIQ, Oracle and SUSE Create Open Enterprise Linux Association for a Collaborative and Open Future". Oracle. August 10, 2023.
  33. ^ "Controversy surrounds Red Hat's "obfuscated" source code release". The H. Retrieved 12 March 2011.
  34. ^ "Red Hat defends changes to kernel source distribution". The H. Retrieved 12 March 2011.
  35. ^ McAllister, Neil (12 Nov 2012). "Oracle: Get your Red Hat Linux patches from us, it's easier. New service lets public browse kernel fixes". The Register. Retrieved 1 August 2014.
  36. ^ "Project: RedPatch". oss.oracle.com. Retrieved 2014-08-04.
  37. ^ a b c "Red Hat Enterprise Linux Updates and Related Kernel Versions". Red Hat. Retrieved 2012-05-16.
  38. ^ "Red Hat Defines a New Epicenter for Innovation with Red Hat Enterprise Linux 9". Red Hat, Inc. 2022-05-10. Retrieved 2022-05-11.
  39. ^ Cattelain, Gil (May 18, 2022). "Hot Off the Presses: Red Hat Enterprise Linux 9" (Press release). Retrieved May 19, 2022.
  40. ^ "Hot Off the Presses: Red Hat Enterprise Linux 9". Retrieved 25 May 2022.
  41. ^ a b "RHEL Codename Conventions". Red Hat Learning Community. 23 May 2022. Retrieved 31 May 2022.
  42. ^ a b "Powering IT's future while preserving the present: Introducing Red Hat Enterprise Linux 8 Beta". 2018-11-14.
  43. ^ a b c "Red Hat Open the Linux Experience to Every Enterprise, Every Cloud, and Every Workload with Red Hat Enterprise Linux 8". 7 May 2019. Retrieved 2019-05-07.
  44. ^ IBM (28 May 2019). "IBM United States Software Announcement 219-234". IBM. International Business Machines Corporation. Retrieved 26 March 2022.
  45. ^ IBM. "IBM United States Software Announcement 219-234" (PDF). IBM. International Business Machines Corporation. Retrieved 26 March 2022.
  46. ^ Timothy Prickett Morgan (10 June 2019). "The Transition To RHEL 8 Begins On Power Systems". ITJungle. Retrieved 26 March 2022.
  47. ^ Vaughan-Nichols, Steven J. (November 5, 2019). "Red Hat Enterprise Linux 8.1 adds live Linux kernel patching". ZDNet. Retrieved 2019-11-06.
  48. ^ "RHEL 8.4 - Final Release". Red Hat Customer Portal. 17 September 2021.
  49. ^ "Red Hat Announces Availability of Red Hat Enterprise Linux 7 Beta". Red Hat. 2013-12-11. Retrieved 2013-12-11.
  50. ^ "2013 Red Hat Summit". See for example this presentation Archived 2016-03-04 at the Wayback Machine
  51. ^ "Red Hat Enterprise Linux 7 Release Candidate Now Available". redhat.com. 2014-04-15. Archived from the original on 2014-04-27. Retrieved 2014-04-27.
  52. ^ "Red Hat Unveils Red Hat Enterprise Linux 7". redhat.com. 2014-06-10. Retrieved 2014-06-10.
  53. ^ a b "Red Hat Continues Platform Innovation with the General Availability of the First Minor Release of Red Hat Enterprise Linux 7". www.redhat.com. 5 March 2015.
  54. ^ a b "Red Hat Enterprise Linux 7.2 now available". Red Hat, Inc. 2015-11-19. Retrieved 2015-11-19.
  55. ^ a b "Red Hat Enterprise Linux 7.3 now available - Red Hat Customer Portal". access.redhat.com. 3 November 2016. Retrieved 2016-11-03.
  56. ^ a b "Red Hat Enterprise Linux 7.4 now available". access.redhat.com. July 2017. Retrieved 2017-07-18.
  57. ^ a b "Red Hat Enterprise Linux 7.5 Released". access.redhat.com. 10 April 2018. Retrieved 2018-04-10.
  58. ^ "Chapter 8. Desktop Red Hat Enterprise Linux 7". Red Hat Customer Portal.
  59. ^ a b "Red Hat Refines Hybrid Cloud Innovation with Latest Version of the World's Leading Enterprise Linux Platform, Red Hat Enterprise Linux 7.6". access.redhat.com. 30 October 2018. Retrieved 2018-10-30.
  60. ^ a b "Red Hat Drives Cloud-Native Flexibility, Enhances Operational Security with Latest Version of Red Hat Enterprise Linux 7". access.redhat.com. 6 August 2019. Retrieved 2019-08-06.
  61. ^ "Red Hat Enterprise Linux 7.8 Now Generally Available". access.redhat.com. 31 March 2020. Retrieved 2020-03-31.
  62. ^ "Announcing Red Hat Enterprise Linux 7.9". access.redhat.com. 30 September 2020. Retrieved 2020-10-13.
  63. ^ Red Hat Enterprise Linux Life Cycle
  64. ^ "6.0 Release Notes — Red Hat Enterprise Linux 6". Red Hat Customer Portal.
  65. ^ "Red Hat Enterprise Linux AS 4 Release Notes". Archived from the original on 2019-04-24. Retrieved 2019-04-24.
  66. ^ "New redhat-release package for Red Hat Enterprise Linux 2.1 Update 7". Red Hat Customer Portal. Archived from the original on 2012-03-11. Retrieved 2012-05-16.
  67. ^ "Red Hat Enterprise Linux Life Cycle". Access.redhat.com. Retrieved 2015-01-20.
  68. ^ "What is the Red Hat Enterprise Linux Extended Life Cycle Support Add-On (ELS), and what is its support life cycle?". Red Hat. Retrieved 2017-01-12.
  69. ^ "Does Red Hat support upgrades between major versions of Red Hat Enterprise Linux?". 10 February 2023.
  70. ^ "Red Hat Enterprise Linux Errata Support Policy". Red Hat. Archived from the original on 2010-04-05. Retrieved 2012-08-11.
  71. ^ "Red Hat Enterprise Linux 3 - End Of Life". Red Hat. Retrieved 2010-01-12.
  72. ^ "Red Hat Enterprise Linux Release Dates". Red Hat. Retrieved 2015-09-30.
  73. ^ "Announcing up to 4 years of Extended Life Cycle Support (ELS) for Red Hat Enterprise Linux 7". www.redhat.com. Retrieved 2024-05-17.
  74. ^ a b "Red Hat Enterprise Linux Life Cycle". Red Hat. Retrieved 2022-10-14.
  75. ^ "What is backporting and how does it affect Red Hat Enterprise Linux (RHEL)?". Retrieved 12 May 2016.
  76. ^ "Why does Red Hat Linux use such an old kernel?". stackexchange.com.
  77. ^ "SO_REUSEPORT on linux". StackOverflow.com. Retrieved 12 May 2016.
  78. ^ "Backport SO_REUSEPORT patch from kernel 3.9+ to help support haproxy graceful restart". Retrieved 12 May 2016.
  79. ^ "Which RHEL version supports the SO_REUSEPORT socket option?". Red Hat. 15 October 2014.
  80. ^ a b c "Red Hat Enterprise Linux (RHEL) Extended Update Support (EUS) Overview". Red Hat Customer Portal. 18 November 2022.
  81. ^ Hughes, Johnny (20 May 2012). "[CentOS] Z-Stream?".
  82. ^ "Red Hat Enterprise Linux Life Cycle". Red Hat Customer Portal.
  83. ^ a b c "Red Hat Enterprise Linux Life Cycle". Red Hat Customer Portal. Retrieved 2020-11-21.
  84. ^ "Red Hat Enterprise Linux 7.8 Now Generally Available". Red Hat Customer Portal. 31 March 2020. Retrieved 2020-11-21.
  85. ^ "Announcing Red Hat Enterprise Linux 7.9". Red Hat Customer Portal. 30 September 2020. Retrieved 2020-11-21.
  86. ^ "Red Hat Enterprise Linux Life Cycle". 2019-08-06.
  87. ^ a b c d e f g h i j k l m n o p q r "Red Hat Enterprise Linux Release Dates". Red Hat Customer Portal. 17 May 2023.
  88. ^ "Red Hat Enterprise Linux Life Cycle". Red Hat Customer Portal. 2019-08-06. sec. "Red Hat Enterprise Linux 8 Application Streams Life Cycle".
  89. ^ a b "Red Hat Enterprise Linux 8 Application Streams Life Cycle". 2019-08-06.

Further reading

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[edit]
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