We have met many people who are considering virtualization of servers in a number of different scenarios. Some of these folks are just getting started with virtualization, which can be a big change in light of shrinking budgets and limited supporting infrastructure such as shared storage. Some folks have already done some virtualization and are tackling the job of virtualizing the “challenging” servers that are running critical back office applications. Some are finding servers with a large amounts of local storage, limited amounts of downtime, or systems that are incredibly sensitive to their software environment. Finally, some folks have been on a long path of virtualization and are within a project or two of becomming 100% virtualized. Whatever the case may be, the common question that comes up is ‘should everything be virtualized?’ As is so often the case in consulting, the answer is often “It depends.” In some cases virtualization will not be possible however desireable. This can be due to incompatibilities, software dependencies, and anumber of other factors. Carefull analysis and management of tradeoffs is key to a virtualization plan.
Another important approach is to keep a broad and open approach to virtualization. For example, in some situationsuse of free virtualization solutions such as the free edition of VMware ESXi (vSphere Hypervisor) or Microsoft Hyper-V can be a reasonable approach. Furthermore, using physical servers may be simpler that virtualization for some applications. So we caution against “virtualization envy” when some organization claims to be 100% virtualized. The real question is how much of the opearting business workload is actually running on the virtualized servers vs. physical servers.
Lastly, we would say this: Any IT department or team is in the process of considering virtualization, therefore carefull analysis and planning as to how to use this new IT tool must be executed. Proper planning also involves management systems and high availability strategies just as any team would consider with physical servers. Virtualization is the root system for cloud operations and while IT teams understand their own private cloud, rigorous understanding of public cloud designs of the virtualization subsystems is paramount to a properly implemented hybrid solution set.