I've interviewed perhaps 30 people for senior virtualisation roles in the last few months and one theme keeps occuring; many virtualisation specialists either ignore the VM workloads or know little about the guest operating systems. This trend is a real worry, if you don't understand what the VM is doing, and have some idea how it works, how are you supposed to ensure it has the right resources, is located on the right cluster, has the right DR profile?

Sure, you can hide behind the "how many IOPS" or "how much RAM" questions, but thats equivalent to an arhictect asking you how many doors and what square footage does your building need without understanding whether its use is residential, office or industrial. OK, the analogy isn't perfect, but you get the point.

Now don't get me wrong, these people understand their particular vistualisation stack and its related software very well - and this is a good thing. But senior roles cannot be as narrow as this. I think the immaturity of the virtualisation industry is partly to blame here. Think back to the early days of Microsoft; very product focussed. Nowadays, Microsoft lead many conversations with customers at a business level. This brings up another bug bare; virtualisation is a technology like many others - its there to solve problems. Too many people are using it as the panacea, "virtualisation is the answer, now whats your problem?". Again, immaturity, and perhaps unbounded enthusiasm are major contributors.

So, a few words of advice for any who are going for a senior job as a virtualisation specialist (e.g. Virtualisation Architect);

1. Consider several alternative solutions to ensure you pick the right one. Its not always virtualisation 
2. Understand the business and technical problem, before jumping to the solution
3. The guest OS and workload will impact how you configure and manage the VM - make sure you understand these
4. Get to know the three main virtualisation stacks, their strenghts, weaknesses, and tehnical differences so you can make an informed decision on which to use and where

Good luck, and I wish you success with you future virtualisation efforts.

Kevin