Price didn’t factor in much a year ago when this article was posted. As you’ll see from the comments, it was a split between people relying on features that one product didn’t support, and people who didn’t need those features and bought cheaper. Has RHEV caught up in the past year? Perhaps. I’ve moved on to a new firm, who is XEN and VMware based, so it’s not really something I’m currently tracking.

Anyway, works for us, but not without a bit of hacking. Thanks for the info.

Thanks for taking the time to comment. I do not understand how you can say RHEV automatically powers down unneeded hosts. Yes, there is a manual button to start and stop hosts, but from what I experienced in my own hands-on investigation is consistent with the product documentation: hosts remain powered on, but idle.

In fact, Red Hat’s datasheet on Power Saver says:

The host will now run idle, consuming significantly less resources – typically 10 to 15% of the power of an active server. If other hosts in the cluster reach the maximum service level the System Scheduler will live migrate virtual machines onto the host and re-balance workload within the cluster.

And the demo here also confirms that hosts are idle — not powered off.

Is there an undocumented configuration option to enable power on/off of servers?

Eric

RHEV has had the capability to power off nodes in a virt cluster since the beginning. You can define a power management strategy for each cluster. When a hypervisor host is not needed, RHEVM will fence a node or nodes, migrating VMs as neccessary. The actual fencing happens via Python (Expect) scripts that access out-of-band management cards in the hypervisor nodes.

A variety of out of band management cards are supported – DRAC5 worked for us until we migrated the stack to Dell PE R610s, and there is (at last check) no fence scripts that can speak iDRAC6. So we’re out of luck for now, but the point of this is – what you’re describing is completely wrong.

We have a handful of folks here where I work (5000+ employee govt. and defence contractor) who get very religious about VMWare, so I am used to your mindset, but please don’t spread inaccurate information.

Yes, I have taken into account that RHEV is a new product and the feature set is not the same as VMware.

Unfortunately, Red Hat has not taken that into account. They are actively promoting their product as equivalent to VMware vSphere. I think we all agree that it is not.

If you can afford to wait a “few years” that is fine. Most cannot.

And yes, my writing is biased toward VMware. I do not pretend to be an independent third-party (they don’t exist, by the way). But everything I write is factual.

Thanks for reading,
Eric