RHEL 6.0 was released in November ... long live RHEL 5.x? Under its commitment to support its enterprise Linux distros for seven years, Red Hat has released 5.6, a new-and-improved version of its older Linux operating platform.
Because 6.0 includes all the latest, greatest, today's announcement has been received with a yawn. But for enterprise users that didn't cut over their production servers to the 6.0 beta version (or who didn't spend the holiday season upgrading their servers), today's additions will be welcome news. In my mind, that means everybody. (If you've moved to 6.0 already, drop a comment and let me know how you like it.)
The two items that will likely jump out at you is that DNS has been upgraded to BIND 9.7, which includes support for DNSSEC. Internetnews.com's Sean Michael Kerner may have said it best when he noted, "As DNSSEC is now enabled in the root zone of the Internet, the time for all DNS servers globally to be DNSSEC enabled is here."
RHEL 5.6 now also officially supports ext4 -- not just as a preview version (dubbed ext4dev). This was already added to both RHEL 6.0 and Fedora 14 and as such Red Hat calls it a "Linux 6 backport." With ext4, the OS can support volumes as large as 16TB. RHEL 6 also supports XFS and GFS2, which scale up to 100TB .. but these were not backported to 5.6.
Also nice is the inclusion of sVirt (SELinux virtualization), which enables Mandatory Access Control (MAC) profiles to be applied to virtual guests.
Obviously, the updated distro includes the latest security fixes to the kernel, a bunch of new or updated drivers including the forcedeth Ethernet driver for NVIDIA nForce devices and Xen Support for Intel Core i7 and Atom Processors. Plus it includes a number of new drivers for 1G and 10G Ethernet (supports Cisco, Intel, and other brands you would expect).
Red Hat claims 5.6 includes 2,000 fixes, including more than 300 performance changes or additional hardware support. Red Hat will continue to support RHEL 5.x through 2014.
Companies may be in no hurry to upgrade to 6.0, despite a much longer list of snazzy improvements because it costs a pretty penny. The base pricing is akin to 5.x -- an entry-level server was $349, and included up to four virtual guests. RHEL 5 offered unlimited guest instances for a single price at the Advanced Server level. In comparison, RHEL 6 allows only a single virtual guest for the entry level $349. A single x86_64 license that allows four virtual guests: $1,199, with 24/7 support, $1,949, with unlimited guests and premium support: $3,249.
And if 2014 rolls around and you still don't want to fork over the bucks to upgrade, last summer Red Hat announced an Extended Life Cycle Support (ELS) contract, that will give you three more years of support.