Linux Penguin

CentOS Version 6.4: What You Need To Know

In March of this year, CentOS gathered all of the Red Hat Enterprise Linux upstream packages released and created the latest version of CentOS for distribution. We are going to talk about some of the changes and additions to this version so you can decide when is the right time for you or your organization to upgrade.

If you want to try it out now without upgrading your own systems, you can head on over to Linux Academy and check out their Linux training tracks. You get a personal server to use during all the online lessons and CentOS 6.4 is one of the distributions available right now.

Few Major Changes
Samba libraries (version 4) have been upgraded to the latest upstream release. This latest update resolves a number of bugs and compatibility issues with Active Directory Domains, particularly those hosted on Microsoft Windows 2012 Server(s). The biggest upgrade however, is that with this release, CentOS is now shipping with the Microsoft Hyper-V drivers. This is significant since it now demonstrates the CentOS commitment to that server virtualization technology and will be a stability watermark for the distribution. Up until this latest release, the driver install was a manual process wrought with problems, particularly in disk performance. This version should perform better than anything prior right out of the gate.

What Else?
This release was not big on changes or additions. Various libraries received their security treatments in stream and several small existing bugs were addressed (see the documentation at the CentOS.org Wiki for specific details. We see new versions of Mozilla Firefox and Thunderbird as well as Xulrunner and some new artwork. A few upstream updates (RedHat) of note are new TLS 1.1 support in NSS, a new ‘fallback’ configuration for firewalls (iptables), new network device drivers (a few updates and additions to the Intel wireless chip support) and the latest Intel processor and chipset support added to KVM round out the most notable additions.

Issues of Note
If you run CentOS in a Virtual Box, you may have some video driver issues until you update Virtual Box to 4.2.12 or greater (OpenGL issues). If you install from scratch and have to use the text installation, you will need to be satisfied with the default partitioning scheme. The text/ncurses based installation STILL does not have a functioning custom partition setup (hello? this has been around since version 5).

Desktop developers are going to be annoyed with this one, especially since it is most likely to affect their work systems as they tend to be ‘older’ systems. The proprietary AMD drivers for ATI cards (2xxx, 3xxx and 4xxx series – integrated or standalone) are NOT compatible with the new X server introduced in CentOS 6.4. The ONLY solution at this time is a downgrade of all of xorg* packages to the versions available in CentOS 6.3. This is NOT the fault of the CentOS folks, this is part of the whole churn that is so frustrating in the X community. Ubuntu thinks they can fix X compatibility by simply breaking everything and ‘doing their own thing’ and although I disagree with the approach, I understand it. X itself has been ‘broken’ for some time and we do not see anyone really scrambling to take ownership of the problems and compatibility issues and get them resolved.

Final Thoughts
Other than security updates, there is no ‘compelling’ reason to rush out and upgrade. In fact, if you are running a development workstation, you may be better off NOT upgrading (or at least excluding all the xorg* updates to save yourself some headaches) until when/if AMD releases legacy drivers compatible with the new Xorg releases. By and large, particularly in a server environment, this new version should be scheduled as part of your next maintenance window since nothing earth shattering is happening at this time.

Terrence T. Cox

A veteran of twenty years in Information Technology in a variety of roles. He has worked in development, security and infrastructure well before they merged into what we now call DevOps. He provides training in Linux, VMWare, DevOps (Ansible, Jenkins, etc) as well as containers and AWS topics.