One of my co-workers, Chris Reed (www.creedtek.com), uses the analogy that the most expensive pet you can get is a free dog. The initial cost is great. How can you get cheaper than $0? However, this transaction is followed by the vet bills, the inevitable property damage and the chewed up slippers. Free dogs rarely have their shots, which puppies need several rounds of. They usually need to be “fixed”, and I like to add in a location chip. Soon, you have shelled out a significant amount of cash on a free pet.
Many people will adopt a similar approach to virtualization, selecting a free product with the assumption that it will save them money. Can that work? Yes. Are there hidden costs to be aware of, and even expect in the near future? Definitely. Can those costs be significant? Yes, and they can be quite significant.
If you are comparing free hypervisors, then it comes down to features. Microsoft includes more features in their free version than VMware, but their features are less robust than the same features from VMware. And as you move into the higher licensing levels to migrate into an enterprise solutions, VMware’s features are significantly more robust. That could mean starting on one hypervisor at the free level, then having to change hypervisors as your environment matures. That can be a VERY painful process.
I wrote more on this topic in my last article “Free virtualization: It’s free for a reason“. I would also recommend going to www.virtualizationmatrix.com for a great break down of features between Citrix, Microsoft and VMware at various versions of their products. Andreas Groth has done a significant amount of research to build that matrix.