What is RHEL Linux?
Red Hat® Enterprise Linux® is the world’s leading enterprise Linux platform.* It’s an open source operating system (OS). It’s the foundation from which you can scale existing apps—and roll out emerging technologies—across bare-metal, virtual, container, and all types of cloud environments.
Red Hat Enterprise Linux is an enterprise Linux operating system, certified on hundreds of clouds and with thousands of vendors. Red Hat Enterprise Linux provides a consistent foundation across environments and the tools needed to deliver services and workloads faster for any application. Red Hat Enterprise Linux reduces deployment friction and costs while speeding time to value for critical workloads, enabling development and operations teams to innovate together in any environment.
Red Hat Enterprise Linux (often abbreviated to RHEL) is a Linux distribution 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. 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" 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 Scientific Linux and commercial forks like Oracle Linux.
Download CD and DVD images or individual RPM packages.
Features and benefits
Expand to the edge
Red Hat Enterprise Linux extends your hybrid cloud infrastructure to the edge—across hundreds of thousands of nodes all over the world. Create edge-optimized OS images, minimize workload interruptions caused by OS updates, transfer system updates more efficiently, and have confidence in automatic health checks and rollbacks.
Mitigate, secure, comply
Red Hat Enterprise Linux takes a practical, 3-point approach to addressing security challenges: Mitigate, secure, and comply. Built-in security features help you defend against threats and stay in compliance with regulatory requirements.
Learn about these features and what makes Red Hat Enterprise Linux equipped to handle security and compliance for your enterprise.
Migrate or upgrade to the latest version
Run purpose-built command line utilities to automate many inventory and remediation steps associated with upgrading your subscription or migrating from another Linux distro. Our consultants can also help operationalize any upgrade or migration, even from non-Linux distros.
As the most deployed commercial Linux distribution in the public cloud, Red Hat Enterprise Linux is certified on hundreds of public cloud and service providers as well as thousands of other types of software and hardware.
A Red Hat subscription offers production-ready code, life-cycle management, software interoperability, and access to experts and tools to help you run your business. Existing customers can take advantage of security, performance, and automation support immediately.
Open source innovation
Get supported access to open source innovation. As a top contributor to the Linux kernel and hundreds of subsystems, we represent your requirements upstream and return with stable innovations.
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 license 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 the 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.
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.
Since Red Hat Enterprise Linux is based completely on free and open source software, Red Hat makes available the complete source code to its enterprise distribution through its FTP site to anybody who wants it. Accordingly, several groups have taken this source code and compiled their own versions of Red Hat Enterprise Linux, typically with the only changes being 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 CentOS, Oracle Linux, CloudLinux OS, Scientific Linux, White Box Enterprise Linux, StartCom Enterprise Linux, Pie Box Enterprise Linux, X/OS, Lineox, and Bull's XBAS for high-performance computing. All provide a free mechanism for applying updates without paying a service fee to the distributor.
Rebuilds of Red Hat Enterprise Linux are free but do not get any commercial support or consulting services from Red Hat and lack any software, hardware or security certifications. Also, the rebuilds 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 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. 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. 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.
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 and 7. 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.
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 and 5, and covers a limited number of packages. Red Hat only supports major version upgrades from version 6 to version 7.