The postman delivered Red Hat Enterprise Linux 6.8 last week, and while the package contents look even more like RHEL 7, it still doesn't include systemd -- a reason many users have avoided moving to RHEL 7.
The latest release of Red Hat Enterprise Linux (RHEL) mainly includes security and management improvements, plus local backup and domain name system (DNS) caching features that are part of the Linux distribution's newer major release. Now, longtime RHEL 6.x users must decide whether to stay with the nearly 6-year-old operating system or move to RHEL 7.
RHEL 7.2 was released in November 2015, but RHEL 6.x is still more widely deployed, according to the company. RHEL 6.8, the eighth maintenance release of RHEL 6, marks a turning point as it moves into Production Phase 2; according to the RHEL lifecycle, there will be no new functionality, except for defect corrections. Before, RHEL 6 was still getting new capabilities and extensions.
Many users prefer the security and stability of RHEL 6, and its long-term support that extends much longer than other Linux distributions, according to Paul Norton, a Linux consultant and owner of San Diego Linux, who works with IT and development managers at scientific and engineering businesses.
For example, some of his clients use engineering software that is only supported on RHEL 6, which has kept them from going to RHEL 7. Others don't need bleeding-edge software, or prefer to steer clear of systemd, and have stayed with RHEL 6, where they are more comfortable and familiar.
The transition from RHEL 6 to RHEL 7 is much steeper than from RHEL 5 to RHEL 7, explained Eric Pronko, senior systems engineer at Carnegie Mellon University in Pittsburgh.
"I personally had a significant amount of resistance to RHEL 7 on its release," he said, because the operating system -- specifically, systemd and the systems that tie to it -- are so different from what came before.
Some IT pros "hate systemd," or find the learning curve in RHEL 7 is too steep and put off migrating, agreed Scott Dowdle, a RHEL user since 1996 and blogger at Montana Linux, who has mostly moved to RHEL 7. One of the main features of RHEL is that it is supported for a long time, so upgrading to a new major version isn't required, he said.
A simpler disaster recovery
For users that remain committed to RHEL 6, RHEL 6.8 incorporates some new features for enterprise users.
The addition of the Relax-and-Recover system local backup archiving tool allows systems administrators to create local backups in an ISO format, which makes disaster recovery simpler, according to Red Hat. That should be useful for organizations running RHEL 6 on physical servers, especially since it can be done on a similar environment, according to Norton.
It could replace tools such as Clonezilla and will be useful when upgrading to a new server, eliminating the need to take it offline, he said. Red Hat also tweaked the default service configurations to disable less safe protocols and cyphers, putting more emphasis on enabling the stronger ones -- particularly TLS 1.2, Dowdle said.
Unbound (caching DNS server) is also available in RHEL 7, and it's used on Fedora desktops and has been added to RHEL 6.8.
Security upgrades in RHEL 6.8 include replacing Openswan with the Libreswan library for virtual private networks (VPNs) security.
RHEL 6.8 also adds features for users that integrate with Microsoft Windows. There are minor enhancements in the Active Directory area and for running RHEL virtualized on a Windows Server under Microsoft Hyper-V, Dowdle said, making integration with Active Directory easier through solid-state drive improvements that include cached authentication lookup and authentication via smart cards. Additionally, it includes updates to KVM so that newer Microsoft Windows versions run better under KVM.
The latest release also adds dmstats for more metrics about storage, giving better visibility into storage use and performance.
An upgrade for upgrade's sake
Even if they don't see any big new benefits of the new release, many IT pros are likely to accept the RHEL 6.8 upgrades to make sure their servers stay current with security patches and fixes.
"There is a lot more new stuff there that I would not have expected for a release so deep into its release cycle," Dowdle said.
Stephen Eatoninfrastructure technical lead for registration and titling solutions, Dealertrack Inc.
Stephen Eaton, infrastructure technical lead for registration and titling solutions at Dealertrack Inc., in Lake Success, N.Y., doesn't see any benefits for his organization from the RHEL 6.8 release. Nevertheless, "I have servers on 6.7 and will be upgraded to 6.8 on the next patching cycle, [although] I can't say there is anything in the release I'm excited to utilize," he said.
Norton agrees that most of the new features in RHEL 6.8 aren't that exciting, although he said he expects most of his clients "are going to be happy with the security updates." None have updated to RHEL 6.8 yet, since most wait a few weeks and listen to the reaction from others.
Robert Gates covers data centers, data center strategies, server technologies, converged and hyper-converged infrastructure and open source operating systems for SearchDataCenter. Follow him on Twitter @RBGatesTT or email him at firstname.lastname@example.org.
The case for systemd Linux containers
How to use RHEL 7 updates to simplify configuration and management
Developers envision new apps for RHEL on ARM servers