Red Hat Enterprise Linux Life Cycle

Overview

Red Hat offers services for each major release of Red Hat Enterprise Linux throughout four life cycle phases—called Production 1, 2, and 3, and an Extended Life Phase.

• Red Hat Enterprise Linux 5 and 6 are offered with 10 years of Production Phase support, followed by a three year Extended Life Phase.
• Red Hat Enterprise Linux 3 and 4 are offered with seven years of Production Phase support, followed by a three year Extended Life Phase. Optionally, during the Extended Life Phase, customers may purchase an Add-On called Extended Life Cycle Support (ELS) that provides support similar to Production Phase 3.

The Red Hat Enterprise Linux life cycle phases are designed to reduce the level of change within each major releaseⁱ over time and make release availability and content more predictable.ⁱⁱ

The Red Hat Enterprise Linux 5 and 6 life cycle:

The Red Hat Enterprise Linux 3 and 4 life cycle:

Details

Software changes to Red Hat Enterprise Linux are delivered via individual updates known as errata advisories through the Red Hat Customer Portalⁱⁱⁱ or other authorized portals. Errata advisories can be released individually on an as-needed basis or aggregated as a minor release. Errata advisories may contain security fixes (Red Hat Security Advisories or RHSAs), bug fixes (Red Hat Bug Fix Advisories or RHBAs), or feature enhancements (Red Hat Enhancement Advisories or RHEAs). All errata advisories are tested and qualified against the respective, active Red Hat Enterprise Linux major release. (For example, a Red Hat Enterprise Linux 6 RHSA will be applied cumulatively to the latest Red Hat Enterprise Linux 6 version and patch set.) All released errata advisories remain accessible to active subscribers for the entire Red Hat Enterprise Linux life cycle. Within each major release of Red Hat Enterprise Linux, any errata advisory (including one released as part of a minor release) will be applied cumulatively to the latest release of Red Hat Enterprise Linux, including any patch sets.

During the life cycle of a major release, Red Hat makes commercially reasonable efforts to maintain binary compatibility for the core runtime environment across all minor releases and errata advisories. If necessary, Red Hat may make exceptions to this compatibility goal for critical impact security or other significant issues. Furthermore, major releases of Red Hat Enterprise Linux contain a limited set of backward-compatible libraries included in previous major releases to allow for the easy migration of applications. Typically, Red Hat applies changes in such a way as to minimize the amount of change and to maintain binary compatibility. Exceptions may apply for controlled package re-bases under certain circumstances.

The following table details the subscription services, including support and software maintenance, performed during each phase of the Red Hat Enterprise Linux life cycle:

Production 1 Phase^iv:

During the Production 1 phase, qualified Critical and Important Security errata advisories (RHSAs) and Urgent and Selected High Priority Bug Fix errata advisories (RHBAs) may be released as they become available. Other errata advisories may be delivered as appropriate.

If available, new or improved hardware enablement and select enhanced software functionality may be provided at the discretion of Red Hat, generally in minor releases. Hardware enablement that does not require substantial software changes may be provided independent from minor releases at Red Hat's discretion.

Minor releases will also include available and qualified errata advisories (RHSAs, RHBAs, and RHEAs). Minor releases are cumulative and include the contents of previously released updates. The focus for minor releases during this phase lies on resolving defects of medium or higher priority.

Updated installation images will be provided for minor releases during the Production 1 Phase.

Production 2 Phase^v:

During the Production 2 Phase, qualified Critical and Important Security errata advisories (RHSAs) and Urgent Priority Bug Fix errata advisories (RHBAs) may be released as they become available. Other errata advisories may be delivered as appropriate.

If available, hardware enablement that does not require substantial software changes may be provided at the discretion of Red Hat, generally in minor releases. New software functionality is not available during this phase.

Minor releases will also include all available and qualified errata. Minor releases are cumulative and thus include the contents of previously released minor releases and errata advisories, including those from Production 1 Phase. The focus for minor releases during this phase lies on resolving urgent- or high-priority bugs.

Updated installation images will be provided at Red Hat's discretion for minor releases during the Production 2 Phase only if required because of installer changes.

Production 3 Phase^vi:

During the Production 3 Phase, Critical Impact Security Advisories (RHSAs) and selected Urgent Priority Bug Fix Advisories (RHBAs) may be released as they become available. Other errata advisories may be delivered as appropriate.

New functionality, new hardware enablement, or updated installation images are not planned for availability in the Production 3 Phase. Minor releases are not delivered during this phase.

Extended Life Phase and Extended Life Cycle Support Add-On^vii:

During the Extended Life Phase, a Red Hat Enterprise Linux subscription provides continued access to previously released content on the Red Hat Customer Portal, as well as to other content, such as documentation and the Red Hat Knowledgebase.

As an optionally available add-on^vii to a Red Hat Enterprise Linux subscription, Red Hat offers an Extended Life Cycle Support (ELS) subscription. ELS delivers critical impact security fixes and selected urgent-priority bug fixes that are available and qualified for a published subset of the packages in a specific major release of Red Hat Enterprise Linux that is beyond the end of the Production 3 Phase. For ELS subscribers, Red Hat will generally continue to proactively provide the Critical Impact security fixes if and when available independent of customer requests.

The ELS Add-On is delivered during the Extended Life Phase for an additional three years after the conclusion of the seven-year Production Phase. ELS is delivered for a limited set of software packages on a specific set of hardware architectures and is available for Red Hat Enterprise Linux 3 and 4 only.

Virtualization

Virtualization provides hardware abstraction for guest operating systems. Abstraction allows a guest that is running an older version of Red Hat Enterprise Linux that does not support the latest server hardware to be easily deployed on a virtualization host that does. In this way, a Red Hat Enterprise Linux 4 guest can be hosted by Red Hat Enterprise Linux 6 on a latest-generation processor.

Red Hat intends to support those versions of Red Hat Enterprise Linux that are still within the Production or Extended Life Phase when run as virtualized guests on later versions of Red Hat Enterprise Linux.

The Red Hat Enterprise Linux virtualization support matrix provides details on the supported combinations of operating systems, versions, and hardware architectures.

Life Cycle Dates

All future dates mentioned for "End of Production 1" and "End of Production 2" are close approximations, non definitive, and subject to change.

Extended Update Support^viii

Red Hat offers the Extended Update Support (EUS) Add-On to a Red Hat Enterprise Linux subscription for those customers who wish to standardize on a specific minor release for an extended period of time. The EUS Add-On allows customers the flexibility to decide when to take advantage of new Red Hat Enterprise Linux features, including new hardware enablement.

Under a Red Hat Enterprise Linux subscription, all available RHSAs and RHBAs are provided for the current active minor release until the availability of the next minor release. By contrast, EUS delivers—for a specific minor release—an independent, extended stream of those Critical Impact RHSAs and selected Urgent Priority RHBAs that are available after that specific minor release and in parallel to subsequent minor releases. For EUS subscribers, Red Hat generally will continue to proactively provide Critical Impact RHSAs independent of customer requests if and when available.

In the following example, the EUS stream associated with Red Hat Enterprise Linux 6.1, which was released in May 2011, will be populated until May 2013 with selected Critical Impact RHSAs and selected Urgent Priority RHBAs that become available.

In Red Hat Enterprise Linux 4, EUS was available for the following minor releases:

• 4.5 (ended January 31, 2009)
• 4.7 (ended August 31st, 2011)

In Red Hat Enterprise Linux 5, EUS is available for the following minor releases:

• 5.2 (ended March 31, 2010)
• 5.3 (ended November 30, 2010)
• 5.4 (ended July 31, 2011)
• 5.6 (ends July 8, 2013)
• 5.9 (available for 6 months after 5.11 availability)

In Red Hat Enterprise Linux 6, EUS is available for all minor releases released during the Production 1 Phase, but not for the minor release marking transition to Production 2 or any minor releases released during the Production Phase. Each Red Hat Enterprise Linux 6 EUS stream is available for 24 months from the availability of the minor release.