The lure of Hyper-Converged for VDI
So you decided to implement Virtual Desktop Infrastructure (VDI). Virtual desktops and app delivery sound sexy, but once you’ve started delving into the nitty gritty, you quickly realize that VDI has many variables. In fact, so many, that you start to feel overwhelmed.
At this point you have a couple of options. First, you can keep doing this yourself, but that will take valuable time. You can hire a VDI engineer to your team, but that also tales time and money to find a great engineer.
Another option is to hire a Value Added Reseller that has done VDI a hundred times. Great idea – I will love you forever, and will do great VDI for you. But I can be expensive.
One particular sticking point in VDI is the sizing of the hardware for the environment. If you undershoot the amount of compute, storage, memory or networking, you risk having unhappy users with underpowered virtual desktops. If you overshoot, you may be chastised for overspending.
Too often I have seen the user profile not properly examined, sized etc. The result is that the derived virtual desktop is low on memory or CPU. The user immediately blames the new technology, not even assigning blame to something they may have done. But the real performance problem culprit may lie somewhere else. However, the user just had his shiny physical machine taken away, and it was replaced with something intangible. Of course, all the problems, whether related to VDI or not, will be blamed on VDI, and possibly the VDI sizing. The bad buzz spreads through the company. Such buzz kills your VDI project faster than performance problems.
So, what is one way to avoid thinking about sizing? Hyper-Converged.
Hyper-Converged means a node in a cluster has a little bit of everything – compute, storage, memory, network. Each node is generally the same but there could be different types of nodes – for example, Simplivity has some nodes with everything, and some nodes only doing compute.
Since most nodes are the same, once you figured out how many average Virtual Desktops in a specific profile fit on a node, you can just keep adding nodes for scalability.
In fact, Nutanix capitalized on that brilliantly when they announced the famous guarantee – once the customer says how many users they want to put on Nutanix, the vendor will provide enough Hyper-Converged nodes to have a great user experience. The guarantee was hard to enforce on both the customer end and Nutanix end. But the guarantee sure had lots of marketing power. Time and time again I heard it from customers and other VARs. The guarantee was a placebo for making VDI easier.
Consequently, you should not just rely on a guarantee for VDI sizing. Sizing should be verified with load simulation tools like LoginVSI and View Planner. Then, the profile of your actual user should be evaluated by collecting user experience data with a tool like Liquidware FIT or Lakeside SysTrack.
Once the data is collected and analyzed, you can decide what number of Hyper-Converged nodes to buy. Hyper-Converged makes the sizing easy because you always deal with uniform nodes.
Once you are in production, you should be monitoring user experience constantly with a tool like Liquidware UX. UX will allow you to always have a solid idea of what your user profiles to. As a result, you can confidently say, “On my Hyper-Converged node I can host up to 50 users.” Thus, if you grow to 100 users, you need 2 Hyper-Converged nodes.
Saying the above is the holy grail of scalability. And therein lies the lure of Hyper-Converged – as a basic VDI building block. That is why Hyper-Converged companies started with strong VDI stories, and only later began marketing for Virtual Server Infrastructure.
And any technology that makes VDI easier, even by one iota, makes VDI more popular. Hail Hyper-Converged for VDI!