Red Hat Enterprise Linux (RHEL) is a Linux distribution developed by Red Hat and targeted toward the commercial market. Red Hat Enterprise Linux is released in server versions for x86, x86-64, Itanium, PowerPC and IBM System z, and desktop versions for x86 and x86-64. All of the Red Hat’s official support and training, together with the Red Hat Certification Program, focuses on the Red Hat Enterprise Linux platform. Red Hat Enterprise Linux is often abbreviated to RHEL, although this is not an official designation.
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”, and added two more variants, Red Hat Enterprise Linux ES and Red Hat Enterprise Linux WS.
Red Hat uses strict trademark rules to restrict free re-distribution of their officially supported versions of Red Hat Enterprise Linux, but still freely provides its source code. Third-party derivatives can be built and redistributed by stripping away non-free components like Red Hat’s trademarks. Examples include community-supported distributions like CentOS and Scientific Linux, and commercial forks like Oracle Linux, which does not offer 100% binary compatibility with Red Hat Enterprise Linux, because Oracle uses a non-standard process to clear the Red Hat brand.
Red Hat Enterprise Linux Server subscription is available at no cost for development purposes. Developers need to register for the Red Hat Developer Program and agree to licensing terms forbidding production use. This free developer subscription was announced on March 31, 2016.
There are also “Academic” editions of the Desktop and Server variants. 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 number of customer contacts can be purchased separately.
It is often assumed the branding ES, AS, and WS stand for “Entry-level Server”, “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:
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”.
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.
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
6.7, also termed Update 7, July 22, 2015; 20 months ago (kernel 2.6.32-573)
1st Day of EUS Window July 22, 2015; 20 months ago
Last Day of EUS Window July 31, 2017; 3 months’ time
6.8, also termed Update 8, May 10, 2016; 10 months ago (kernel 2.6.32-642)
1st Day of EUS Window May 10, 2016; 10 months ago
Last Day of EUS Window May 30, 2018; 13 months’ time
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
7.1, also termed Update 1, March 5, 2015; 2 years ago (kernel 3.10.0-229)
1st Day of EUS Window March 5, 2015; 2 years ago
Last Day of EUS Window March 31, 2017; 6 days ago
7.2, also termed Update 2, November 19, 2015; 16 months ago (kernel 3.10.0-327)
1st Day of EUS Window November 19, 2015; 16 months ago
Last Day of EUS Window November 30, 2017; 7 months’ time
7.3, also termed Update 3, November 3, 2016; 4 months ago (kernel 3.10.0-514)
1st Day of EUS Window November 3, 2016; 4 months ago
Last Day of EUS Window November 30, 2018; 19 months’ time
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