Self-proclaimed genius, and ruler of the Internet. System admin the rest of the time

RedHat Enterprise Linux 6 Beta 1 has finally been released as a public beta. It is available as an ISO from the public RedHat FTP site.

A couple of days ago, I decided to play with the beta, and I discovered (as I had expected) that there are a lot of significant differences between RHEL5 and RHEL6.
The the main difference which I found to be very frustrating is that there is no longer any support for Xen dom0.

I had heard about RedHat’s decision to stop supporting Xen, but I did not think that this would mean they would stop shipping it with the distribution.

The loss of dom0 support means that you can no longer use RHEL as a Xen virtualization host, rather only as a guest under other Xen supporting distributions.

Xen was dropped in favor of Kernel-based Virtual Machine, which is a  virtualization infrastructure included with the Linux kernel. Linux KVM is a hardware-assisted virtualization infastructure which requires the CPU to have a special CPU feature called Intel-VT on Intel CPUs and AMD-V on AMD CPUs.

KVM has limited paravirtulization support, but I found in my very simple tests that fully paravirtualizaed guests inside Xen had much better performance.

This latest release of RHEL also means that my RHCE will soon expire. I am hopeing to get re-certified as soon as I can. At the same time, I am also considering taking the “Red Hat Certified Virtualization Administrator” course and exam, but I still have some time to think over that.