Getting to grips with VDI

Getting to grips with VDI

Gaining insight into the world of virtual desktop infrastructure and concepts.

In the next few weeks, I will provide some insight into the world of virtual desktop infrastructures (VDI). I will introduce the background of the technology, the pros and cons, alternative options and the future of VDI.

On the bandwagon

Virtualisation vendors quickly came up with a solution for housing desktops in a virtual environment and called it VDI.

To fully understand what VDI is and why it is a key focus for many organisations, let me start by asking a few questions:

What is a virtual desktop infrastructure (VDI)?

A very simple question, but I have come across plenty of IT owners who have not heard of VDI or simply don’t know the acronym. As is the question, the answer is simple. VDI provides the ability to house a desktop operating system in a virtual environment, which has typically been reserved for use with server platforms.

Where does VDI originate from and why is it of interest to many businesses?

VDI originated from the success of server virtualisation over the past few years. Organisations were and still are moving more and more to implement virtual infrastructures for their production environments to ease the pain of managing physical server environments, reduce hardware footprints and all the other associated issues and costs, like data centre space, power and air conditioning.

Virtualisation has been so successful that it has almost become the norm for an IT infrastructure. Because IT managers and CIOs saw how successful the virtual platform could be, questions and ideas started to appear around the feasibility of moving desktops into the virtual environment as well. In theory this would enable a secure, easy-to-deploy desktop that is housed in the data centre and has all the inherent benefits of server virtualisation, such as high availability, consolidation and machine templates.

Not surprisingly, the virtualisation vendors quickly came up with a solution for housing desktops in a virtual environment and called it VDI.

So how does everything fit together and what is needed to adopt VDI?

Because a desktop environment is much more (or should be) interactive than a server environment, user interaction with a virtual desktop is a given. Since the desktops are housed in a data centre, a remote connection for user interaction is needed.

Most VDI vendors make use of technologies such as terminal services as the interface to connect to desktops in the data centre. Much like traditional desktops, each user has his/her own virtual desktop with a desktop operating system such as Windows XP or Windows 7. Connection to this desktop is managed and maintained using a VDI connection broker such as VMware view or Citrix Xen Desktop, to name a few. The connection is made from any device that supports this software, such as a thin client, desktop or laptop. To adopt a VDI solution, a resilient virtual platform with enough capacity is needed to house the environment, and all the desktops, connection broker software and a client device are all necessary.

If an organisation has already deployed a server virtualisation platform, on paper, adopting a VDI strategy to enhance the business seems cost-effective and easy to produce a decent return on investment (ROI).

However, dive into it a little more and the opposite is true. The cost of a thin client is very similar to purchasing a desktop, except without the desktop operating system. There are a few tricks to housing a desktop operating system in a virtual environment from a Microsoft perspective. A very particular licensing type is needed, and existing desktop OEM licences cannot be transferred unless software assurance was purchased with them. For a worthwhile VDI environment, a connection broker such as VMware view or Citrix Xen Desktop is recommended. Although virtual desktops use significantly less resources than virtual servers, additional resources are still needed.

Add all this together and there’s a solution that requires quite a bit of investment, above and beyond, and merely offers desktops in a data centre environment. Simply moving desktops from physical machines into a virtual data centre does not really reduce support costs, because if a company had 400 desktops before, they still have 400 desktops simply housed in another location.

Benefits such as easy desktop deployment are realised because of the inherent virtualisation benefits. Other issues such as software deployment and support still remain. So I pose the following question: is it worth investing in a VDI solution or is it more beneficial to concentrate on creating a well-managed desktop infrastructure? How different are they really? That discussion is covered in part two; watch this space…

Data Management