VDI: Not just for big business

Time is the scarcest commodity for any IT pro. There’s never enough to get everything done, whether you spend it fighting fires, rolling out new applications, or supporting the user base. And this scarcity affects IT shops of any size — from the armies supporting Fortune 100 companies to the one beleagured employee supporting a small business.

One result of this time shortage is that many small businesses now use the same tech once reserved for large enterprises. For example, I’m seeing a growing number of small businesses adopt full-blown server virtualization, but not for the consolidation, power, or space benefits that might motivate a larger organization. Rather, they do it simply because it would be impossible for one or two people to manage the work if systems weren’t virtualized, especially given the current aversion to hiring new employees.

The same is becoming true of desktop deployments. If you’ve directly supported even a small number of thick desktops, you already know how much time you can sink into them over the simplest of issues. You name it: malware, dead hard drives, Windows patches, application upgrades, OS upgrades. They suck up enormous amounts of time, disrupt productivity, and only get worse as the number of users grow. Deploying VDI can often solve all of these problems while also providing a range of other benefits, such as allowing employees an easy way to work from home.

Overcoming ROI misconceptions

The biggest challenge to implementing VDI in a small environment is justifying the capital expense. If you’ve spent time playing with ROI calculators or reading case studies, you’ll see that VDI deployments are generally considered to be islands unto themselves — that is, dedicated virtualization and storage infrastructures designed and implemented solely to support the VDI implementation. At these scales, it’s generally not difficult to reflect the ROI necessary to justify the capital cost required to build the infrastructure. However, at much smaller scales, it becomes nearly impossible to show capital cost savings.

If you’ve done the math and found that implementing VDI for 50 to 100 users is more expensive than sticking with thick desktops, don’t think you’ve missed something — it absolutely is. Shoehorning VDI into environments of this size almost always requires combining the virtualization of desktops with a pre-existing server virtualization infrastructure — not typically a great idea in larger environments, but it can work exceptionally well in smaller environments. If you can make it work, the savings derived from operating your servers and desktops from the same virtualization platform — combined with the operational cost savings of not hiring more help — will provide you with the necessary cost justification.

What you’ll need

If you have a pair of fairly recent server virtualization hosts attached to shared storage, you have most of what you need to get VDI fired up. Necessary additions come in the form of software licensing, more RAM for your existing hosts, or perhaps another virtualization host. However, you can usually get a small pilot rolling without adding anything at all.

The most important thing to keep an eye on when considering this approach is the loading and capabilities of the shared storage in use. Most VDI deployments won’t result in a very large storage capacity footprint by utilizing features (such as VMware’s Linked Clones) that dramatically decrease data duplication when deploying many similar virtual machines from a common base image.

Be aware, though, that each active user will generate a small transactional disk I/O load that scales linearly and can easily dwarf the load generated by your servers. Even if your users generateonly around 10 IOPS each, if you have 75 of them, that’s an average increase of 750 IOPS — which your storage may or may not be able to handle. Given the expense involved in expanding even an entry-level SAN deployment, this is a critical piece of information to know before you try to sell VDI as a solution.

What you’ll get

Though no technology is perfect, VDI can deliver a great desktop experience for your users while reducing the time you spend managing them. Being able to deploy a fleet of nonpersistent desktops from a single base image gives you the ability to perform tasks such as software deployment and patching once rather than many times. Better yet, problems such as malware infestations are often solved simply by asking the user to log out and log back in; on their next login they can receive a completely clean image with their own personal settings layered on top. Though there are a raft of other features, these two alone make investigating VDI well worth the time.

If you already run a server virtualization infrastructure, there’s no reason not to give VDI a try no matter what the size of your organization. At worst, you’ll gain experience with a technology that may well underlie the desktop environment of the future. At best, you’ll find a solution that suddenly makes desktop support much, much easier.

This article, “VDI: Not just for big business,” originally appeared at InfoWorld.com. Read more of Matt Prigge’s Information Overload blog and follow the latest developments in storage at InfoWorld.com. For the latest business technology news, follow InfoWorld.com on Twitter.