The hidden challenges of desktop virtualization
It is meant to be the panacea to cure all ills; the taming of one of the last poorly-managed parts of the IT infrastructure. Desktop virtualization promises to solve a lot of problems, but are we in danger of underestimating its challenges?
Server virtualization is now a mature concept in enterprise IT. CIOs have understood the benefits of consolidating server hardware for a while. But virtualizing the desktop is a relatively new phenomenon that companies are getting grips with.
On a traditional PC desktop, the operating system is installed directly on the hardware, and is therefore linked with it. Desktop virtualization separates that operating system from the hardware, hosting it on a server instead. There are several benefits.
Desktop virtualization assists in information security, in the sense that you're no longer running an application on the endpoint device. Application data is held on the server, which makes it harder to steal.
Other benefits include lower-cost desktop hardware, because ‘fat’ PCs can be replaced with thin clients. This can reduce capital expenditure and hardware maintenance on the desktop, while also saving electricity and air conditioning costs.
However, there are also some potential challenges.
Firstly, planners may miss some of the hidden costs of a virtualized desktop infrastructure. These include enterprise storage. Between 35-40% of the cost of virtual desktop integration is in enterprise storage. An average Windows user might have 10Gb of space. When a lot of desktops are virtualized, that storage requirement begins to mount.
These issues can be mitigated to some extent. For example, a shared operating system model in which multiple users share the same desktop (using Windows Remote Desktop Services) is an option. However, organizations might then need to invest in user virtualization technology, which stores each employee’s personal desktop settings to give them a personalized desktop experience.
CIOs shouldn’t underestimate the user experience when virtualizing desktops. The PC was called ‘personal’ for a reason. Employees may resist having those desktops wrenched away from them and hosted somewhere else, particularly if it means standardizing them and removing some of the user's own personal settings.
Different users may want different applications, which means that administrators may need to configure different desktops at the back-end to suit different groups of employees. The more variations on a single desktop that are required, the more complex the initiative becomes, and the more likely that support and administration costs will increase at the back end.
In any case, not all applications designed for the desktop may be easy to host on a virtualized system. Some that require intensive graphics work, for example, such as computer automated design or video editing, may be best left on a local machine, which limits the scope of desktop virtualization projects for some organizations. Microsoft provides support for hardware-enhanced graphics with RemoteFX, but design teams must still evaluate applications carefully on a case-by-case basis.
One of the biggest areas that people underestimate is the process of transforming applications from the existing estate to the new one. Applications must be tested in a virtualized environment to ensure that they will function as expected.
Even if storage and application considerations can be made to work in a pilot program, scaling the project to hundreds of thousands of users may place unexpected strains on the system. For example, ‘bootstorms’ can be a problem in large virtualized desktop scenarios. Hundreds of users all trying to log on at the same time in the morning can overwhelm a network, creating show-stopping bottlenecks that can dramatically decrease productivity.
This in turn can lead to calls to the helpdesk, which can quickly become swamped. That helpdesk will also find its role changing, as the kinds of support queries alter. Is a support team equipped to handle an increased number of application-related queries, for example, as hardware maintenance issues decrease at the desktop?
what's my conclusion?
Clearly, then, while desktop virtualization holds promise for many organizations, CIOs should go to it with their eyes wide open. You need to know the operating system levels of your servers and desktops. You need to know your networking infrastructure and everything else inside-out before you start deploying a production system.
Perhaps more than any other IT-related project, virtualizing something that has been on users’ desks for 30 years is a holistic project that touches every part of your technology portfolio, and affects your core processes. Are you ready to take it on?
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