Virtualization is the key technology for the cloud. Its ability to separate the OS and application from the hardware enable it to best deliver on-demand cloud services. Charles King, Principal Analyst at Pund-IT said it best: "Without virtualization there is no cloud - that's what enabled the emergence of this new, sustainable industry."  But, how can IT organizations leverage virtualization to create their own private cloud?

Virtualization Evolution:  The Three Stages

Typically, organizations advance through three stages of virtualization.  The first stage is characterized by virtualizing the “low hanging fruit.”  Consolidation and disaster recovery strategies are initiallyfocused on garnering the capital expenditure savings from virtualizing applications that have low business impact.

The second stage of virtualization is when things get tricky due in large part to the complexity created in stage one. This is where most enterprises are today.  Many CIOs now have a “virtualization first “policy, requiring IT to virtualize for the cost benefits. Yet, IT is concerned about how to maintain high service levels. In this second stage, organizations may have started to use IT resources including applications, servers, storage, and networks as pools of resources that can be managed in aggregate rather than isolated silos.  Thinking about IT resources as an entire system becomes important for fully leveraging the power of virtualization, as it allows IT to move resources on demand to efficiently balance computing loads and use capacity more efficiently.  The issue of performance requires attention at this stage as well.  Organizations may have experienced unexpected poor performance in stage one and know they will need help to assure performance of the business critical applications (Exchange, SQL, SAP) that are virtualized in stage two and beyond.

Thus, it’s critical in stage two that organizations obtain the right management tools beyond what comes “out of the box” with their virtualization software.  Tools, such as infrastructure performance management solutions, that can help enterprises optimize while they virtualize are essential.  These tools enable IT to get the visibility and control they need to troubleshoot and assure performance, optimize performance and capacity, plan server and storage requirements, and manage service levels to advance from stage two to stage three.

Stage three is characterized by virtualizing mission critical applications and a transformation in which virtualized resources shift to become a pool that is managed at the pool level.  This allows workloads from different business units to become fluid. At this point, infrastructure is shared and IT must embrace a service management focus to deliver the private cloud in which physical and logical resources are made available through a virtual service layer across the enterprise.

Figure 1: The three stages of server virtualization evolution.

Mastering Stage Two:  Focus on Performance and Capacity Management

Let’s take a closer look at what’s required of infrastructure performance management solutions that can enable the move to stage three and the private cloud.

1) Troubleshooting Virtual Infrastructure

IT administrators should look for infrastructure performance management tools that provide cross-domain visibility and analysis for effective troubleshooting across their entire pool of resources.  Effective root-cause analysis requires a comprehensive view of all elements within the infrastructure including automatically mapping each element and its interdependences from application to virtual and/or physical server to storage array disk group.

This category of tools must also have an Infrastructure Response Time (IRT) metric to troubleshoot performance issues.  Defined as the time it takes for the system to perform work submitted by an application, IRT directly shows how responsive the system is.  IT infrastructure owners can use this metric to quickly demonstrate to application owners whether poor end-user performance is due to infrastructure issues, such as resource contention or hot spots, or something outside of the infrastructure.  Problem resolution that used to take hours or days can be reduced to minutes.

Figure 2: Infrastructure Response Time is a metric used to quickly identify where infrastructure issues exist.

For example, it’s not uncommon for organizations to use “virtualization best practice” planning for consolidation, but be unable to fully assess the storage requirements and how they factor into performance problems.  One organization that migrated their storage “as is” ended up having phantom slow-downs that resulted in finger pointing and multiple fire drills.  After installing an infrastructure performance management solution that automatically mapped the topology and highlighted bottlenecks and configuration problems, they were able to show and prove that the data store was the bottleneck and that the IO was not being delayed at the array.