The VMworld Europe PR blitz is in full swing (hats off to many of my old BEA marketing compatriots!). And as it was at VMworld in Vegas back in September, VMworld Europe is all about the cloud. The only problem (if you're VMware) is that the cloud isn't all about virtualization.
In fact, you don't need virtualization for cloud computing. Despite what they'd like you to think. Blasphemy? Maybe, but let me explain...
While I was away on vacation last week a great discussion took place on this topic, started by Christofer Hoff's simple, incomplete thought that he lobbed to his readers: "How many of you assume that virtualization is an integral part of cloud computing? From your perspective do you assume one includes the other? Should you care?"
The thing that got him asking the question was a difference in the way Google and Amazon deliver and define their respective cloud services (PaaS v. IaaS, from my perspective). I, too, noticed an assumptive thread that consistently weaves its way through most conversations about cloud computing (both the internal and external varieties): the assumption is that when people are talking about dynamic, on-demand, cloud-style resources, of course there will always necessarily be virtualization underneath it all.
Not true, actually.
First, though, credit needs to be given to market-leader VMware (currently sipping their share of kir royales in Cannes, I'm sure) and all the virtualization providers, really, for changing the conversation about how a data center can be run. For years, siloed and static application stacks kept anything dynamic or elastic from getting very far. Virtualization changed that. It allowed a first step, a separation of underlying hardware from the software running on top.
Virtualization has really opened up the thinking of IT ops folks. Now that these previously inseparable items are able to be sliced, diced, moved around, expanded, contracted, and the like, all bets are off. In fact, it's probably the change in thinking brought about by virtualization that allows us to even consider talking about cloud computing in the first place.
However, virtualization isn't the silver bullet that enables cloud computing. In fact, it isn't even required. It's one of several types of technologies that can be employed to help deliver the service your business requires from a set of compute resources, either in your data center (an internal cloud), outside your data center (an external cloud), or both (a hybrid of the two).
Internal clouds will mean a mix of physical and virtual
When we at Cassatt talk to customers about implementing internal clouds, it's a discussion about using what you already have running in your data center -- apps, servers, virtual machines, networks -- with no changes, but applied in a different way. Instead of the compute resources being dedicated to particular apps, the apps (with the help of our software) pull what's needed from a big pool (cloud) of available compute supply. If our customers are any indication about what data centers really look like, some of those compute resources will be physical, some virtual. And, with the economy the way it is, people want to squeeze every bit of capability out of whatever mishmash they are running, even if it's not ideal. That means there will be a little bit of everything.
Alessandro Perilli of virtualization.info quoted VMware CEO Paul Maritz as saying that starting later this year, when the first generation of vSphere platforms will be out, there will be no technical reason not to virtualize 100% of your data center. I bet not. Why? We asked the VMware users that came by our booth at VMworld in September '08 that same question: "You're eventually going to virtualize everything, right?" Every one of them responded, "No, no, of course not." They cited cost, performance, management, and a host of other reasons. Translation: reality gets in the way. So, if you aren’t going to virtualize everything, aren't you still going to want to make the best use of all your data center resources? The answer is yes from what we hear.
External and hybrid clouds: will anybody have the same infrastructure?
External clouds might be a different story. You'll use whatever it is that your external service providers have. They could have a fully virtualized set-up. Or, they may have a more mixed environment. Again, Perilli quoted Maritz saying that virtualization is the only viable way to do cloud computing. Nope. It's an option. Of course, if you can apply your internal IT ops expertise to your external cloud work, too, it's a win (as Christofer Hoff notes in another post). It just won't always be possible.
When it comes to hybrid clouds -- moving from internal to external clouds and back, or some federated way of mixing and matching compute power from both -- the ability to be able to leverage physical and virtual, and even to leverage VMware, Citrix, Microsoft, Parallels Virtuozzo, etc., is going to be really important. Nobody is going to have the same stuff. The real world is heterogeneous.
Which brings me to some general commentary about VMware's European announcements:
Things that sounded good from the VMware announcements
There were definitely some items that sounded positive from VMworld Europe this week. Maritz talked about interoperability, and was quoted by Alex Barrett of SearchServerVirtualization.com as saying, "What we fear is the emergence of a couple highly proprietary uberclouds. There's an old joke about a California hotel that you can check in to but that you can't check out of. We don't think that should happen." (Of course, I always thought that was the Roach Motel, but maybe the point's the same.)
Kudos to Maritz for talking up internal clouds and the move to hybrid/federated clouds. Chuck Hollis from EMC underscored Martiz's validation of the private cloud concept, calling it a "big thing" in his post, because "of all the different cloud models I've heard...this is the first one that I think can work for real-world enterprise IT." In creating their "software mainframe," Maritz talks about wanting to help change the decision about whether to run a workload on an internal or external cloud from being a can't-change-it architectural one to being an operational one. Management will be at the "service level and not at the plumbing level." To me, that sounds like the right vision, and a great reason to base your infrastructure on policy-based automation. But I'm a little biased on that topic.
Some things VMware forgot to mention in Cannes (and not by accident)
As with the initial announcement of vCloud and the VDC-OS (now vSphere) back in September, though, there are some underlying problems when you try to fit the vision slides with the reality (Ken Oestreich did a good overview of these back then). First, you'll probably have more than one virtualization technology in your IT systems. This is either by design or by happenstance (like, say, from acquisitions), but it's going to be the reality in many cases. VMware's vision of "hyper-vising the data center" (as Chris Mellor at The Register calls it) ignores that.
Second, and more fundamentally (and as I noted already), you'll have both physical and virtual servers in your data center. You'll want to think through an internal cloud strategy that takes that into account.
Reuven Cohen’s post on the announcements hits the nail on the head on both of these points: "As for being interoperable, VMware is saying that its various management tools will only work on top of the VMware hypervisor. In other words, physical servers and servers virtualized by Microsoft, Citrix or any other vendor will not be compatible with the vCloud initative. Summarized, we're interoperable as long as it's VMware."
It's not unexpected that VMware would ignore these points. But *you* need to keep them in mind in trying to reconcile cloud computing versus virtualization. Virtualization can certainly help deliver a cloud computing infrastructure either inside your data center, or via a cloud service provider. But it's only one of the components, not the main driver. Delivering your business requirements as efficiently as possible -- that's the important thing.
I recommend digging through the comments in Hoff's blog entry that I mentioned at the start of this post. There are a stack of good comments there from Alessandro Perilli of virtualization.info, Andre Gironda, Anthony Chaves, James Urquhart, and others. James says "abstraction is what is important to cloud computing, not virtualization -- a big difference." Mike Rothman of securityincite.com views "cloud computing as what is being delivered and virtualization as one of the ways to deliver it."
Great points. See what I miss when I go on vacation?