At the launch of vSphere 5 on the 12th July VMware did publish some information about the free version of ESXi. This has been called the vSphere Hypervisor since 4.1, to distinguish it from the ordinary ESXi. On 4.0 there was lot of confusion about whether ESXi was free or not, so it was a good move to place the free version into its own product name.
The free vSphere Hypervisor had some very reasonable limits, for example it could not be attached to a vCenter Server and you could not run any writable remote scripting tools against it and could only be managed directly from the vSphere Client. The idea was to let small companies run VMware virtualization in a simple and free way and perhaps make them interested in moving up to a licensed version of vSphere.
For version 5 of vSphere Hypervisor there has been some very contradictory information from VMware. On the information site for the version 5 of the product we can see on the “compare” tab that a virtual machine running on free vSphere Hypervisor could use up to 1 TB of RAM, which basically means that there is no specific memory limit on the virtual machines running on the free version. We can note the much smaller amounts of RAM available for Hyper-V and XEN, at 64 and 32 GB/vm.
But on the FAQ tab, next to the page above, we are told that the vSphere Hypervisor only allows 8 GB of vRAM. This information is also on the bottom of the page.
The concept of vRAM is defined in the licensing documents as the total amount of RAM given to all virtual machines. This would mean that no matter how much physical RAM you have in the host running the free Hypervisor you could only start virtual machines with a total of 8 GB allocated.
Since we do not know which one of these two statements are correct it is to early to see what will happen to the free product. Unfortunately if the 8 GB vRAM limit is correct than it is hard to see many use cases for the vSphere Hypervisor and will most likely make users look at the free Hyper-V Server from Microsoft as a replacement.
We will hope that VMware clarifies this confusion soon and also hope that the 8 GB vRAM limit is not correct, since it will make the product relatively useless and will either force users to a paid vSphere edition or to some competitor. I hope we will still see the free VMware product as an alternative for the smallest businesses.
Update: Changes in the license model for free vSphere Hypervisor on 3rd of August.