Red Hat Enterprise Linux

Red Hat Enterprise Linux (RHEL) is a Linux distribution produced by Red Hat and targeted toward the commercial market, including mainframes. 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 Red Hat's official support and training, and the Red Hat Certification Program center around the Red Hat Enterprise Linux platform.

Red Hat Enterprise Linux is often abbreviated to RHEL, although this is not an official designation.

Red Hat Enterprise Linux 6 has been postponed for undisclosed reasons. Although Red Hat claims to supply major releases every 18 to 24 months, over 36 months (as of 14th March, 2010) have elapsed since the first release of Red Hat Enterprise Linux 5. Red Hat has not yet confirmed a release schedule.

When Red Hat releases a new version of Red Hat Enterprise Linux, customers may upgrade to the new version at no additional charge as long as they are in possession of a current subscription (i.e. the subscription term has not yet lapsed).Red Hat's first Enterprise offering (Red Hat Linux 6.2E) essentially consisted of a version of Red Hat Linux 6.2 with different support levels, and without separate engineering.

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.

Verbatim copying and redistribution of the entire Red Hat Enterprise Linux distribution is not permitted due to trademark restrictions. However, there are several redistributions of Red Hat Enterprise Linux—such as CentOS—with trademarked features (such as logos, and the Red Hat name) removed.

Version History

The various Red Hat Linux versions have little different Errata Support Policies. These are the versions:

Red Hat Linux 6.2E (Zoot), 27 March 2000

Red Hat Enterprise Linux 2.1 AS (Pensacola), 2002-03-26

Red Hat Enterprise Linux 2.1 ES (Panama), May 2003

Red Hat Enterprise Linux 3 (Taroon), 22 October 2003. Uses Linux kernel 2.4.21

Red Hat Enterprise Linux 4 (Nahant), 2005-02-15 (Beta released 2004-09-27). Uses Linux 2.6.9

Red Hat Enterprise Linux 5 (Tikanga), 2007-03-14 (Beta 1 released 2006-09-07, Beta 2 released 2006-11-16). Uses Linux 2.6.18

5.1, also known as Update 1, 2007-11-07 (Beta released 2007-10-10)

5.2, also known as Update 2, 2008-05-21 (Beta released (2008-03-13)

5.3, also known as Update 3, 2009-01-20 (Beta released 2008-10-29)

5.4, also known as Update 4, 2009-09-02 (Beta released 2009-07-01)

5.5, also known as Update 5, TBD (Beta released 2010-02-10)