Hyper-V Server R2: a few additional thoughts

A few weeks ago I wrote a tutorial on how to deploy Hyper-V R2 on the IBM BladeCenter S where I demonstrated, among other things, how to LiveMigrate from one blade to another. I didn't spend too much time commenting on the implications this will have in the market. In this article, I'd like to comment on some of those potential implications.

Reading my piece you might have had the impression that I was "backing" Microsoft and putting Hyper-V R2 on the spotlight. That was not my intention: in fact the geek at the bottom of my heart just wanted to give it a try, as easy as it is. While I was pretty much happy with what I have seen, I was certainly not implying that Hyper-V R2 will be able to match VMware Enterprise technologies (both current and future). In fact, I don't honestly think that this is the case. Part of the misunderstanding is that, for some reason, this industry has grown with the stereotype that a virtualization product that is capable of moving a live workload from one server to another is to be considered enterprise-grade. VMotion has become the industry benchmark for being an enterprise product. I want to challenge this stereotype.

My article created a bit of confusion around this concept. "I saw your article. Are you saying that Microsoft is going to be on par with VMware?" is a common question I have heard a lot lately. I want to use this new article to give you the "other side of the coin" regarding these two important technologies Microsoft is going to bring to the market that are LiveMigrate and CSVs (Cluster Shared Volumes). While having these two capabilities in the new product will help Microsoft to overcome some limitations they have today for some deployment scenarios, this doesn't mean these features could be used in all scenarios (specifically Enterprise scenarios).

The devil is in the detail, so when you start digging a bit into the LiveMigration technology, for example, you can find that:

"..... On a given server running Hyper-V, only one live migration (to or from the server) can be in progress at a given time. For example, if you have a four-node cluster, up to two live migrations can occur simultaneously if each live migration involves different nodes....."

The full story is here: http://technet.microsoft.com/en-us/library/dd443539.aspx

This obviously is documentation that relates to an early beta of the product. But if they are going to stick with these limitations, it would be hard to imagine wide deployments in enterprise scenarios where you might require multiple live migration tasks going on cluster-wise at any point in time for resource optimization reasons. So assuming Microsoft (or Citrix with their new Essentials for Hyper-V package) will come out with some sort of DRS-like product in the R2 timeframe, they might not have the underlying infrastructure ready to leverage these add-on tools.

The same goes for Cluster Shared Volumes: the devil is always in the details. If you have read my previous article you might have had the impression that CSV will deliver pretty much what VMFS delivers today. Well, apparently yes, but again, if you dig a bit into the details you will find out some limitations that might not be relevant for small deployments but might be show-stoppers for enterprise deployments.

At the time of writing, these slides were publicly available at this link. Kudos to Microsoft for not hiding these details and for letting the people know about the limitations.

While it appears at first that CSVs are a "transparent" technology, the reality is that as soon as you start pushing the envelope, they are not. How many enterprise IT organizations today leverage storage replication technologies to implement Disaster/Recovery scenarios? Based on my experience I would say many of them. Hyper-V R2 with CSVs will break this common implementation pattern if they won't be able to overcome this limitation. A pattern that I would imagine all these enterprise customers want to continue to leverage and something that is not just bound to current VMware deployments as it's a technique that is being leveraged by UNIX and Mainframe deployments as well to achieve High Availability and Disaster Recovery.

These are just two examples. As I said, supporting techniques that allow a live workload to fly from a physical server to another is just one aspect, but probably not even the most important. The fact that you have a small Cessna - and so you can technically fly - it doesn't mean it's the most optimal, secure and comfortable means of transportation to go from Milan to New York. For that you want to fly on a 767 (and in business class, if possible!). Of course there are a lot of Cessnas around as they fit a part of the market.

On the other hand, as I said in my previous article, Microsoft has a tremendous asset: they are making (almost) everything available for free. Which leads to at least a couple interesting comments.

Does the price discussion really matter anyway?

The first comment is: does the price discussion really matter anyway? The Microsoft pricing strategy is so that when you have properly licensed your Windows guests (typically via either Windows Server Enterprise or Datacenter SKUs), your underneath Microsoft Hyper-V virtual infrastructure is already licensed by definition. And this is true today. Suppose you have 50 Windows guests to deploy on four 2-socket servers for example. Most likely the cheaper way to license these 50 guests is via the Windows Server 2008 Datacenter SKU which is licensed per physical socket and provides unlimited number of guests. If you do so, it doesn't really matter whether you want to use Hyper-V 2008 Server or a full-GUI Windows 2008 Server w/ Hyper-V or a GUI-less Core Windows 2008 Server w/Hyper-V as your parent partition. You have the right to use everything you want for free including the Failover technology (Microsoft Cluster Server). This excludes the MS Virtual Machine Manager but this won't change in the Hyper-V R2 time frame. So this claim that with Hyper-V R2 they will have more stuff for free is a bit misleading in my opinion in the sense that they already effectively provide many things today (not just the Hyper-V Server SKU) for free.

There is a caveat to this, though, and it boils down to how customers are going to license the Windows guests. The analysis above assumes that customers are going to buy brand new licenses for their new deployment (because they had OEM Windows licenses on their old physical servers that could not be repurposed, for example). If the customer has Windows licenses that they can repurpose on the new virtual infrastructure, then the discussion on the cost of the virtual infrastructure itself is no longer trivial. And, yes, there will be a big bonus in this regard during the R2 timeframe - as the free Hyper-V Server R2 version will have more features and fewer limitations than the current free version. The pricing discussion can get very complicated, as mentioned in my blog a few months ago. It would be interesting to see some statistics on how customers have currently licensed their legacy physical servers.

Last but not least, I am assuming that these customers are using Windows guests on their Hyper-V infrastructure. While Microsoft supports a limited number of Linux distributions (today SUSE, but they announced future support for Red Hat, too), I don't see too many Linux-only customers leveraging Hyper-V for their virtual infrastructure deployments.

Clearly the Microsoft virtualization strategy is different than the VMware virtualization strategy

The second comment regarding the (virtual) price war is this: clearly the Microsoft virtualization strategy is different than the VMware virtualization strategy. And the pricing strategy reflects that. I wrote another article on this topic which I invite you to read. I am attaching hereafter the picture for your convenience because I want to use it to back my point.

In a nutshell, Microsoft makes money out of the red part whereas VMware makes money out of the blue part. Microsoft is probably going to stick with their "Virtualization is a value item of the OS" strategy for the time to come if the pricing schema for Hyper-V R2 (due early next year) is what they are pitching today. Basically what they are doing growing the blue part, and giving it away for free. The only way they can sustain this is by continuing to make money on the red part. This has at least a couple of implications that are worth underlining:

  1. Their Linux strategy is pretty much opportunistic (well, it's obvious and totally expected after all - it's a dumb statement) in the sense they want to give customers with a "few Linux servers here and there" the possibility to leverage the Hyper-V infrastructure these customers are using for the majority of the (Windows) VMs. Even though a Linux shop (probably) would not want to use Hyper-V for technical (or religious) reasons, it wouldn't even make sense for Microsoft to go down that path because they would need to make the blue part technologically compelling on its own while giving it away for free. There would be no revenue stream for Microsoft in such a scenario so probably not worth the effort for them.
  2. Microsoft will not have a business interest in making the blue part grow too much as long as they are going to give it away for free. This means that they won't be able to afford to be so aggressive in the Virtual Appliance space because the JEOS concept is pretty dangerous to their current business model as you may detect from the picture (the smaller the red part is the less leverage they have). Unless they radically change their software licensing model - which I wouldn't rule out- I don't see how they could sustain an aggressive move toward this JEOS concept. Consider also that the smaller the red part is, the easier it could be to migrate to a different OS for the ISV. This is a generic statement obviously and might not be applicable to specific situations.

All in all what Microsoft is doing is interesting and it will benefit customers because it will keep VMware honest in what they are doing - in terms of both technology and pricing. My speculation is that this is going to be a two-horse race in the long run between VMware and a virtual agglomerate comprised of Microsoft and its historical partner Citrix. There are concerns and rumors in the industry - admittedly, I am personally backing them - that Citrix has sort of lost interest in battling at the XenServer level, which is now being distributed for free. Some people are speculating that Citrix is shifting their strategy to expand and provide value on top of someone else's basic virtualization offering (namely Microsoft Hyper-V) and losing focus on their own commodity hypervisor and management offerings (XenServer). Similar to what they are already doing with XenApp expanding the core Microsoft Terminal Services technology.

There is no question that the aggressive pricing move from Microsoft in the R2 time frame will garner some reaction from VMware. I don't have any insight but I wouldn't be totally surprised if VMware was going to provide VMotion either for free or in one of the less prestigious future vSphere SKUs. There are enough technology deltas, on top of VMotion, that will differentiate VMware from Microsoft (especially for enterprise deployments) that will allow the guys in Palo Alto to continue to charge premium prices if they want to.

However, I think that VMware will be at a fork sooner or later: they could either continue to charge a premium for their unmatched features to fill a need some of the Enterprise customers have (and that no one in this industry can or will match), or they could substantially lower their prices to appeal many more customers - especially those that can't afford their technologies. The theory is that you could earn $1,000 either charging 1,000 customers $1, or charging 100 customers $10. This always holds true unless you figure out a way to charge 900 customers $1 and 100 customers $10. Their Acceleration Kits are an attempt to achieve that value proposition, but what Microsoft is doing in the R2 time frame might require a revisiting of the current VMware portfolio layout (which I am sure is in VMware plans). Of course, we need to remember R2 is still about a year away so VMware has some time to think about this.