For those of you who follow VMware products closely, the past couple of weeks have been quite interesting. VMware has announced vSphere 5.0 which has a lot of new exciting features and as always, bigger limits for resources that people are unlikely to hit… ever! However, it is unfortunate that this version of vSphere is making headlines not because of its features but due to changes in the licensing model which changes from being “Per Processor (CPU) with Physical RAM” model to a “Per Processor (CPU) with pooled vRAM entitlements” model. I won’t bore you with all the licensing details as you can find more details about this on the web and in the vSphere 5.0 licensing whitepaper but will just quickly explain the issue with it. According to the new model, you no longer have limits on the cores in a CPU socket or physical RAM in your hosts, however, the vRAM your “powered on” VMs can consume in total must be “equal to or lower than” the total amount of vRAM allowed by your “vSphere license type” times “the number of CPU licenses” per vCenter instance. The issue people are not happy with is vRAM entitlement per vSphere Edition CPU. For example, an “Enterprise” CPU license allows for 32GB of vRAM, whereas an “Enterprise Plus” allows for 48GB.
Why is that an issue? The answer depends on how you’ve built your environment. I would like to think most organisations are like mine: a good number of VMs with a reasonable amount of vRAM, consolidated on hosts with dual or quad multicore CPUs with 72-128 GB of RAM, running either “Enterprise” or “Enterprise Plus” licenses. They also have “best practices” applied to their environment i.e. don’t give any more vRAM/vCPUs to your VMs than needed and have at least a third of the physical RAM on hosts available free. Organisations with such an environment will generally be fine with this model.
However, I also recognize that there are organisations where VMs require large amounts of RAM, potentially requiring 6-10 CPU licenses to run just one VM under this model, even if it doesn’t require that number of CPUs! Matters are made worse by the fact that such organisations don’t have just one such VM – they generally have several, multiplying the problem even further. It is that kind of organisations that are set to lose from this licensing model and are therefore, not happy at all… and quite rightly so! Such organisations were quick to get on the virtualisation bandwagon quite early on and built their environments on the best product available at the time (vSphere in case you’re wondering :-)) and it seems that they’ll get punished for that.
Keeping all this in mind, it’s not a surprise that there is a lot of protest on Twitter, Blogs and VMware’s own forum. The cynic in me thinks that it’s a marketing ploy by VMware to float this before the release of the product to “test the waters” and given the reaction, I think they’ll backtrack or at least increase the limits on vRAM entitlement per VMware edition. Let’s see what happens in the coming days.
Thinking long-term, it seems that the time has come for pure VMware datacenter-based organisations to start thinking about other virtualisation products e.g. XenServer and Hyper-V etc. These products are maturing fast and while they still have some catching up to do, they are good enough for the virtualisation needs of most organisations – at least for most of their VM estate. Organisations can do that while keeping their mission-critical applications/VMs still on vSphere. At least, doing so will freeze or slow down their licensing costs. Starting now would be a good thing so that experience is developed in the meantime and you are not caught out when VMware makes the licensing model even more “challenging”. Justifying the ever-increasing cost of vSphere to management will only get tougher as time goes by – unless of course, VMware is forced to compete by lowering their prices significantly. Strategically, I wouldn’t like to wait for that improbable event and will start moving to other products while I have time.
Update: Well, as expected, VMware announced today that vRAM entitlement on the various vSphere 5.0 editions is being increased. In case of Enterprise and Enterprise Plus, it has been doubled i.e. to 64 and 96 GB per CPU respectively. While this will satisfy a lot of customers who were uneasy with the original entitlement limits, it does seem that this licensing mechanism is here to stay. Considering that, keeping all eggs in one basket seem to be a dangerous strategy for the future.
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