The Migration Team's Optimism is usually on the having the same licensing cost in the target VM environments. So at first glance; they say the licensing (related with the Oracle Licenses) cost should remain the same. The flexibility will increase, the cost stays flat. This is also the goal, actually.
But what I say is ; you are optimizing for flexibility while ignoring the fine print. Oracle’s licensing is not based on what the VM is limited to, but on what the VM is capable of accessing.
If you are using VMware, Microsoft Hyper-V, or any non-Oracle virtualization platform that does not employ "hard partitioning" (and they typically do not by default, or lets say Oracle doesn't accept their partitioning capability as hard partitioning), your licensing burden is likely to increase dramatically. You are forced to license the entire underlying physical capacity of the host cluster that the VM can potentially migrate to.
Think about it: Your small, 8-vCPU VM is sitting on a cluster with four physical hosts, each having 32 cores. The total physical core count is 4 X 32 = 128 cores. Apply the standard Oracle core factor (say, 0.5 for Intel/AMD). You might suddenly be on the hook for 128 X 0.5 = 64 licenses, not the 8 you planned for.
The cost savings you anticipated from virtualization are instantly wiped out. Isolation is the key, and non-Oracle VM solutions struggle to provide the licensing-level isolation we need.
The Oracle Solution
This is where Oracle developed solutions come into play. Oracle VM (OVM) or Oracle Linux /KVM. These platforms are explicitly designed to support hard partitioning. With KVM's CPU pinning, for example, you can logically and technically restrict a VM to a subset of the physical cores, and Oracle accepts this as the boundary for licensing.
You may say: we already invested heavily in VMware infrastructure! We can't switch now.
I Say; that is a classic case of operational convenience trumping financial risk.
Respect the licensing rulebook. It is often more complex, and more expensive, than the technical architecture.
That’s enough for today. Check your contracts before you virtualize.
