The benefits of virtualization have been clearly defined for quite a while now.  This article does a good job explaining the challenges at every stage of the lifecycle: readiness assessment, planning and design, implementation, and ongoing workload optimization and support.

Readiness Assessment. The key objective of this stage is to assess if the server infrastructure is ripe for virtualisation and if benefits can be fully realised. This involves analysing the existing infrastructure, reviewing the overall health of IT assets, identifying which applications and servers are candidates for virtualisation and developing the roadmap that outlines the transition from a physical to virtual infrastructure. A key consideration is server capacity utilisation and performance, looking at both the current snapshot as well as the historical trend. In addition, application demands on the servers must be evaluated.

Planning and Design. This stage involves architecting a scalable solution and then creating a detailed implementation plan, the key objective being to align business demand to IT strategy. This involves choosing an optimal virtual machine configuration to transform a physical server to a virtual platform, sizing the hardware resource required to host selected virtual machines and clustering the hosts into a host farm. It is critical to ensure that infrastructure and service quality performance as perceived by end-users is not negatively affected by virtualisation.

Implementation. During the implementation stage, IT must employ monitoring capabilities to ensure both application and server performance are not negatively impacted as a result of virtualisation. Any design deficiency, performance issue or hardware problem detected must be quickly resolved. A service-centric performance management solution implements automated discovery, dynamic report provisioning and offers before-and-after analysis.

Ongoing Workload Optimisation and Support. Service-centric workload consolidation and optimisation is an integral part of ongoing support to fully realise virtualisation benefits and maximise ROI. The key objectives of this stage include cost-effective delivery of agreed service quality levels, and the ability to ensure high availability and accelerate problem resolution. A service-centric performance management solution provides real-time and historical performance data that can help IT administrators objectively make the right optimisation decisions, keeping the workload in mind. It also enables pre-emptive troubleshooting and fast problem resolution.

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