Before engaging in a virtual desktop solution, the key question is, "What do you need?" As a virtualization architect, I have been involved in countless design and implementation projects. These range from simple proof-of-concept projects for 200 users to migrations for global implementations of 30,000 users. I have seen too many projects fail simply because the right questions were never asked.

One of the first items to determine is which flavor or flavors of VDI to use. Will traditional session-based computing (for example, hosted applications only) suffice or do you need to provide a full desktop? Will users need dedicated resources or can they share resources? Which applications will be available within the VDI space; all or just the most critical? How tightly controlled or locked down will you want this new environment to be? As you can imagine, there is no right and simple answer. In most environments, the answer is a mixed-bag solution.

When considering VDI, there are many factors to choose from, all of which will impact the design decisions. These factors include application compatibility (first and foremost), performance, manageability, scalability, storage, upfront capital costs, and long-term operating costs. Additional factors are reliability, ease of use, mobility, flexibility, recoverability, fault tolerance, and security. In the end, a technology solution should be there to support the business; the business should not be there to support the chosen technology. This means that IT departments cannot work in a vacuum. The driving forces must be what is good for the business and what empowers the application users.

Your choice of VDI solution should be based on your business needs. To fully understand your needs and how they relate to VDI, your entire computing environment must be analyzed. The factors to understand when preparing for a virtual desktop solution include user data, personalization, application management, image management, and device management. These are business drivers that illustrate how users work in the current environment, and they must be understood for successful adaptation in any new environment.

Analyzing your user data

User data includes personal documents, application data, and shared corporate data, all of which must be identified and managed. Home drive assignment, folder redirection, profile management, exclusions, and file synchronization are all viable methods to manage user data in a VDI environment. In order to gain the full benefits of mobility and flexibility within VDI, user data should be managed as its own layer to keep it separate from the operating system, as shown in the following figure:

Virtual machine layers

Infrastructure planning

The entire virtual desktop solution will still need physical infrastructure to support operations. This infrastructure will need to be designed for cost, scalability, and reliability. This includes analyzing your current capabilities to determine whether you can grow your current infrastructure or if you need to create a brand new design. Some organizations will choose new environments as part of a capital project budget. This aids in design and deployment since it becomes a parallel effort to existing operations. Chapter 3, Designing Your Infrastructure, will explore infrastructure design in detail. Have a look at the following figure:

VDI layers

With so many layers and so many options from Citrix (as well as other vendors), the challenge becomes determining the right fit for your environment. There is no easy answer to this conundrum since each organization is different, with diverse goals and objectives.

The following are multiple real-world examples from consulting engagements. These may help you decide which types of VDI are the right fit for you:

Just like there is no one solution to VDI, there is no magic bullet when it comes to a successful deployment. However, there are some tried and true elements, demonstrated in the following figure, which will help you succeed:

Basic project methodology

The basic methodology of any IT project should follow something like this:

I use a slightly different model when deploying virtual desktop solutions. The first and foremost phase is assessment and discovery. The focus should be on high-level strategy and business drivers during this phase. This is the most critical element since all future decisions will hinge on this analysis. Once all the requirements and expectations are defined, determining the best solution for your environment can proceed.

Once the base analysis is complete, the project moves to a design phase. During design, the results of analysis and business requirements are translated into a high-level technical architecture. This includes determining the hardware, software, and all infrastructure components. Once approved, this high-level architecture becomes the design plan.

During the build phase, all of the technology and infrastructure is put in place. This might include building out the data center presence or simply creating the VDI components on top of the existing infrastructure. Once a base build is complete, the environment is ready to test and validate.

The testing phase should include base functionality testing, capacity testing, application integration testing, and user acceptance testing. Testing results are used not only to validate functionality and performance, but also to validate scalability and design decisions. If testing reveals a change in the baseline, the design should be modified as well. Testing is an iterative process that must be repeated with each change to ensure optimal quality and project success.

In smaller environments, or when time is sensitive, the design, build, and testing phases can be consolidated into a single effort (building and testing while designing). However, this is risky and can sometimes lead to delays or overruns.

The pilot phase should be integrated as part of the overall project plan. This may be part of the testing and validation phase, or it may occur once the initial testing is complete. Successful pilot programs are phased in to increase server loads and user counts, and they should encompass multiple use case scenarios. A pilot should mimic production just on a smaller scale. Pilot testing results may lead to baseline or design changes, and subsequent testing cycles may be necessary. However, note that an extensive pilot program is critical to organizational acceptance and project success. You are better off identifying critical issues during a small pilot phase than during a major production rollout.

The last step, of course, is production rollout. Production rollout should be established in phases to keep support manageable as well as to monitor impact on the infrastructure and the overall system performance. An often overlooked key component to production rollout is communication. This includes setting management and end user expectations properly and user training. Open communication will also ease concerns users may have over the state of their desktop. The time spent properly communicating, or over communicating, is quickly recouped through reduced help desk calls.

The following diagram represents the iterative process of IT project management. Notice the weight on analysis as well as the iterative processes, check points, and the phased rollout:

Enhanced project methodology

Managing your project

Communication is critical not just for customer satisfaction, but also to manage the project as a whole, including identifying any changes in scope, timelines, and budget. There are six key factors to ensure your project is successful, which are:

• Managing the scope (what is being done)
• Managing the schedule (timelines)
• Managing the budget (avoiding cost overruns)
• Ensuring quality (everything works as planned)
• Managing risk factors (avoiding the big pitfalls)
• Ensuring customer satisfaction (did you meet the project goals)

The following figure represents the six components for successful project management:

Project management components

Customer satisfaction is critical. This is often overlooked in the IT world as our customers are commonly our coworkers. I was involved in one project that was on time, on budget, and worked. However, the project was a failure because the end users were never properly assessed and what was delivered was not what was needed or wanted.

According to a 2012 survey by McKinsey & Company of large IT projects:

• 45 percent go over budget
• 7 percent go over time
• 56 percent deliver less value
• 17 percent fail so miserably that they threaten the company's existence

  Note

  My good friend from the Marines likes to remind me of their saying, "Slow is fast." This means that slow is smooth, smooth is fast, therefore slow is fast. In other words, you can't rush quality.

In this chapter, we explored the building blocks of a virtual desktop infrastructure. We looked at different models to deliver virtual desktops, including hosted virtual desktops, hosted shared desktops, session-based computing, and application virtualization. We also discussed the various layers of desktop virtualization and we looked at scenarios to help determine the right fit for your environment. You may find that you will need a mix of models and solutions, which is not uncommon.

In addition to looking at the various virtual desktop components, we also discussed building a road map to success. It is not good enough to have a proper design; you must be able to deliver the design successfully. To do so requires some project planning and project management skills, the most notable of which is communication.

In the next chapter, we will look at further defining our virtual desktop environment, including understanding our users and applications in order to build our use cases. We will also look at assessing our current environment and fine tuning our strategy for our new environment.