Red Hat Enterprise Linux derivatives

Red Hat Enterprise Linux derivatives are Linux distributions which are based on the source code of Red Hat Enterprise Linux.

History

Red Hat Linux was one of the first and most popular Linux distributions. This was largely due to the fact that, while a paid-for supported version was available, a freely downloadable version was also available. Since the only difference between the paid-for option and the free option was support, a great number of people chose to use the free version.

Red Hat made the decision to split its Red Hat Linux product into two: Red Hat Enterprise Linux for customers who were willing to pay for it and Fedora which was made available free of charge but gets updates for every release for approximately 13 months.

Fedora has its own beta cycle and has some issues fixed by contributors who include Red Hat staff. But its quick and nonconservative release cycle means it might be suitable for some users. Since the release of Fedora, Red Hat has no longer made binary versions of its commercial product available free-of-charge.

Motivations

Red Hat does not make a compiled version of its Enterprise Linux product available for free download. However, Red Hat has made the entire source code available in RPM format via their network of servers. The availability of the complete source code of the distribution in RPM format makes it relatively easy to recompile the entire distribution. Several distributions were created which took Red Hat's source code, recompiled it then released it.

Features

The Red Hat Enterprise Linux derivatives generally include the union setClarifyme|date=May 2008 which is included in the different versions of RHEL. The version numbers are typically identical to the ones featured in RHEL so that the free versions maintain binary compatibility with the paid-for version which means software intended for RHEL typically runs just as well on a free version. Relatively few changes need to be made to the distributions. However, RHEL used to use its Red Hat's own Up2date technology for providing updates. For convenience, several of the free alternatives ship with yum replacing up2date, something which makes providing mirrors for upgrades significantly easier. Red Hat Enterprise Linux 5 and above releases uses yum as its native system for providing updates, with up2date being just its frontend.

Legal

The free distributions are expressly permitted by free software licenses, primarily the GNU General Public License upon which Red Hat's distributions are based. So, from a copyright perspective, they are entirely legal. However, Red Hat is extremely protective of its trademarks so the free distributions must remove all trademark restricted mentions of Red Hat from their distributions.

Where distributions (e.g. CentOS) have not been deemed sufficiently thorough in removing references to Red Hat, they have received warnings from Red Hat's legal counsel. CentOS received such a notice seeking to have it remove all mention of Red Hat's asserted trademarks from their website and their distribution. CentOS now refers to Red Hat as the "Upstream Vendor" and a "Prominent North American Enterprise Linux Vendor ( [http://www.pnaelv.org/ PNAELV] )."

List of Red Hat Enterprise Linux derivatives

Ordered by popularity on DistroWatch

* CentOS
* Scientific Linux
* X/OS Linux
* Startcom Enterprise Linux
* White Box Enterprise Linux

The following derivatives require payment to download or update:

* Lineox
* Oracle Enterprise Linux
* Pie Box Enterprise Linux

The following derivatives have ceased production:

* TaoLinux - 4.0 i386 Final Release Available on 2005-04-20; 3.0 Update 4 available on 2005-01-10, Ceased production on 2006-06-14. The web site includes instructions for updating to "CentOS" for continued updates

External links

* [http://lwn.net/Articles/128952/ Revisiting RHEL Clones]
* [http://linuxmafia.com/faq/RedHat/rhel-forks.html rhel-forks]