Published: November 12, 2007   |   Updated: February 25, 2008

Before beginning to plan for and design a virtualization infrastructure, an organization needs to determine which parts of its environment to include in the design. The goal of this initial step is to define the scope of the virtualization infrastructure. Virtualization can be deployed across the entire enterprise, or to specific hub locations (a regionalized approach), or to individual satellite offices (a decentralized approach). This section examines each of these options.

This step drives decisions related to how organizations implement virtualization. This information helps determine how the computing environment is intended to run, allows for mapping requirements to a virtual infrastructure, and defines the mode of operations following the virtualization implementation. Because details relating to workloads and other technical decisions vary for each scenario, this guide was designed as a review of each scenario’s required tasks, decisions, and questions. If an organization is considering multiple options, it should complete the steps in this guide for each option.

Option 1: Enterprise Deployment

This option involves deployment of virtualization technology to the entire organization, including corporate data centers.

Benefits

• Delivers standardization across the enterprise and the associated economies of scale.
• Maximizes the return on investment that can be realized by the virtualization project.

Challenges

• Upfront costs of the virtualization project are all incurred before the benefit is fully realized.
• High risk, because of the large number of systems that will be affected.

Option 2: Hub Deployment

This option involves deployment of virtualization technology to one or more hub locations. Hubs are physical locations where there are concentrations of users, computers, and/or network connectivity. Resources within the hub may be provided to additional satellite locations.

Benefits

• Provides a pilot environment in which to prove the process and benefits of virtualization before deployment on a wider scale.
• Can deliver standardization across a region and the associated economies of scale.
• Increases the return on investment that can be achieved by the virtualization project when compared to a decentralized approach.

Challenges

• Upfront costs of the virtualization project are relatively high.
• Medium risk, because a significant number of systems will be virtualized at one time.
• Disruptive, since numerous changes will be made at the same time.

Option 3: Satellite Deployment

This option involves deployment of virtualization technology to one or more satellite locations. Satellite locations are smaller than enterprise or hub environments and often have limited network connectivity to the rest of the environment because of bandwidth constraints.

Benefits

• Upfront costs of the virtualization project are relatively low.
• Lower risk, because a smaller number of systems will be virtualized at one time.
• Provides a pilot environment in which to prove the process and benefits of virtualization before deployment on a wider scale.

Challenges

• Potentially creates a non-standard configuration in smaller, remote locations.
• More complex to implement since satellite offices often lack dedicated technical staff with expertise to optimize systems, which makes support and troubleshooting more costly.
• Limited return on investment that can be achieved by the virtualization project when compared to a larger implementation.

When implementing virtualization in hub and/or satellite locations, organizations may have two primary infrastructure options: They can build a virtual infrastructure within the hub or satellite office itself, or they can move server-related resources to a centralized hub or data center location.

Evaluating the Characteristics

The following tables compare the characteristics of the options.

Validating with the Business

When deciding which portion of the infrastructure to virtualize, business stakeholders should ask questions similar to the following to ensure that they have a complete view of how the planned infrastructure affects the business:

• What is the primary reason for implementing virtualization? Business goals should determine which portions of the infrastructure to virtualize—for example, reducing data center costs by reducing the number of physical servers as well as consolidating applications and workloads. Another business goal may be to reduce deployment time for new applications and operating systems. Virtual machine (VM) deployment requires significantly less time than physical machine deployment.
• What is the expected timeline for moving to virtualization? In many cases, organizations start with a limited deployment in order to gain expertise with the technology and to test various configurations.

Decision Summary

Decisions about which part of the infrastructure to virtualize should be based on the specific needs of the organization. The scope of the virtualization project drives decisions in future steps related to capacity requirements. Although there is no single “best” approach to follow, ensure that the entire organization is aligned with and supports the selected approach before continuing the planning process.

Additional Reading

• Virtual Server 2005 Case Studies at https://www.microsoft.com/windowsserversystem/virtualserver/evaluation/casestudies/default.mspx provide information on how various organizations have implemented virtualization technologies.
• For information on how Microsoft IT has deployed server virtualization technology, see the Technical Solution Brief, “Server and Data Center Consolidation: Microsoft IT Enhances Cost Savings, Availability, and Performance,” at https://www.microsoft.com/technet/itshowcase/content/svrdatactrconsoltsb.mspx.
• Windows Server 2008 Hyper-V library at https://technet2.microsoft.com/windowsserver2008/en/library/5341cb70-0508-4201-a6da-dcac1a65fd351033.mspx.
• Windows Server 2008 Hyper-V Resources at https://www.microsoft.com/virtualization/resources.mspx#documents.