Guest Author
Popularly referred to as RHEL, Red Hat Enterprise Linux, is a Linux-based distribution designed by Red Hat for the commercial market. Although it is a commercial product, the company consistently makes its source code freely available, which has been instrumental towards the development of several community-based Linux distribution platforms including CentOS and Fedora.
Red Hat Enterprise Linux
After its initial release in February 2000, Red Hat went on to release Enterprise Linux version 2.1 in 2002 followed chronologically by the release of RHEL 3, RHEL 4, RHEL 5, RHEL 6 and subsequently RHEL 7 which was made available to the market in December 2013.
Differences between RHEL Versions 5, 6 & 7
Red Hat Enterprise Linux, like many other operating systems or Linux distribution platforms, consistently makes improvements on previous versions and several critical changes before the nesest version is released. The following are some of the categorical differences between Red Hat Enterprise Linux versions 5, 6, and 7.
1. Kernel
RHEL 5 was released with Kernel code name Tikanga which was based on Fedora core 6. This version also came with Kernel version 2.6.18-8 which was generally available on March 15, 2007.
Santiago, the code name for RHEL 6, was based on a mix of Fedora 12, Fedora 13, and several modifications; and came with an initial release Kernel version 2.6.32-71 which was made available on November 9th, 2010.
However, with version 7, Red Hat made a big jump by launching this version with Kernel version 3.10.0-54.0.1 which was released on December 11, 2013. RHEL 7 has Kernel code name Maipo and is a mix of Fedora 19, Fedora 20, along with several modifications.
2. Default database
Both RHEL 5 and 6 make use of MySQL for database management while version 7 makes use of MariaDB. MariaDB is a community driven database manager based on MySQL.
3. GUI interface
Red Hat Enterprise Linux versions 5 and 6 make use of GNOME 2 while version 7 makes use of GNOME3 and KDE 4.10.
4. Load balancer technology
RHEL 5 and 6 both use Piranha load balancer technology while version 7 relies on Keepalived and HAProxy technologies.
5. Cluster resource manager
Red Hat Enterprise Linux versions 5 and 6 both use RGmanager for cluster resource management while 7 uses Pacemaker.
6. Boot loader
As with most older Linux distributions, RHEL 5 and 6 both use GRUB (GRand Unified Bootloader) 0.97 which is a boot loader from the GNU project. Red Hat Enterprise Linux 7 however uses a more stable boot loader version in GRUB 2.
GRUB 2 also supports installation of additional firmware types such as BIOS, EFI and OpenFirmware.
7. Command for file system check
Command “e2fsck” is required for file system checks in RHEL 5 and 6.
However, Red Hat changed this command for RHEL 7 by switching to “xfs_repair”.
A side by side comparison of all three versions is shown below.
| Criteria |
RHEL 5 |
RHEL 6 |
RHEL 7 |
Kernel | Tikanga | Santiago | Maipo |
Default database | MySQL | MySQL | MariaDB |
Desktop/GUI interface | GNOME 2 | GNOME 2 | GNOME 3 and KDE 4.10 |
Load Balancer technology | Piranha | Piranha | Keepalived and HAProxy |
Cluster resource manager | RGmanager | RGmanager | Pacemaker |
Boot loader | GRUB 0.97 | GRUB 0.97 | GRUB 2 |
Command for file system check | “e2fsck” | “e2fsck” | “xfs_repair” |
Kernal Version | 2.6.18-8 | 2.6.32-71 | 3.10.0-54.0.1 |
Initial Release Date | 03-15-2007 | 11-09-2010 | 12-11-2013 |
Who Uses Each Version?
Red Hat Enterprise Linux is built for businesses who need a platform to launch multiple applications simultaneously and virtualize environments. This is the reason why multi-nationals such as Adobe, Barclays, Lufthansa and McDonald’s all use it. Almost 90% of Fortune 500 companies also rely on Red Hat for the versatility of the platform and Red Hat’s award winning support.
Most enterprises are most likely to use RHEL 7 as older versions can be easily upgraded and it also provides the most stable foundation for launching their applications.
Whichever version you choose to use, you can do so with the assurance that Red Hat Enterprise Linux versions 5, 6, and 7 each deliver 10 years of support and an extended life support. During this support period, Red Hat continues to make efforts to ensure that the versions’s binary remains compatible with the core run-time environment even with several update releases.