For every functional and well-managed VDI implementation out there, there are seven to 10 that are its polar opposite -- there are a lot of broken VDI out there.
How do you know if your virtual desktop infrastructure (VDI) deployment is broken? Consider these questions:
- Do you ever field complaints from users who lost data after an image recompose?
- Do users bring in devices from home to browse the Web because video and audio don't work well in VDI?
- Is your density of virtual machines (VMs) per host lower than 35?
- Do you struggle with users who access the environment remotely?
- Does your whole network slow down when users are logging on for the day or during an image recompose?
- Do you avoid or delay doing a recompose because you've had problems in the past?
- Do any employees or executives outright refuse to use VDI because their old PC is easier to use or worked better than virtual desktops do?
- Are you managing the virtual desktops with the same tools that you use for the physical desktops?
If you answered yes to one or more of these questions, then your VDI implementation is probably broken.
VDI should make everyone's life better. After all, it isn't a redeployment of an old system the way refreshing your PCs every four years is. VDI is a more advanced technology. If you can't honestly say that your life is better or that your job is easier because of VDI, then it's time to take action.
Fixing a broken deployment
Fixing VDI may seem daunting, but it doesn't have to be a difficult process. Start with your user base and make sure you genuinely understand what their needs are. Look for tools that help you measure and observe what users need, such as Liquidware Labs' Stratusphere or Lakeside Software's SysTrack for VDI assessment. Both tools measure application use, user activity and a host of other metrics that tell you the use profile of your population. You can also deploy Stratusphere on both physical and virtual desktops to compare the two.
Measurement will tell you only the quantifiable aspects of your user's needs, however. For the rest, you need to get in the field and observe them working. Know your users. Is someone left handed? Do any of your users have accessibility needs? Do you have the guy that leaves 30 apps open at a time? What about someone who needs to stream music through their headphones while working to drown out distractions? These user-specific issues can lead to serious dysfunction when VDI isn't built to account for them.
Once you know the user population, then you have to ask if your infrastructure is designed for them. To that end, I present to you -- based on extensive experience -- the Truth of Architecting VDI:
1. You need dedicated hosts for VDI. Those hosts should only have the desktop VMs on them. All supporting VMs (connection brokers, access servers and so on) need to reside on other hosts.
2. You must have a storage strategy -- specific to your VDI implementation -- that removes operational IOPS from your primary storage. VDI eats storage performance for breakfast. Putting those IOPS on the same storage that's driving your database applications is a mistake.
Look at dedicated, use-case specific storage tools such as Tintri VMstore to get the VMs off the primary storage. Don't want to add another SAN to your network? Then consider doing away with physical storage for your desktop OSes entirely with a tool such as Atlantis Computing's ILIO technology. ILIO will provision your VMs into host memory, thus removing the IOPS from your SAN. But to do this, you need superior user-personality management.
3. You must have a user personality management system. By this I mean, that you must recognize the components that make up a user's "personality." That includes personalized settings, user-created data, application stack and departmentally or user-installed applications.
4. You can't manage VDI with old tools. Products such as Liquidware Labs' ProfileUnity can often replace conventional methods for managing the desktop environment. For example, you can reduce or possibly eliminate your Group Policy Objects. Many readers will immediately dismiss this thought, but I encourage you to avoid that instinct. VDI is about innovation; you should open yourself to that kind of change.
5. Understand that VDI is not a one-size-fits-all technology. You may have groups of users that need better multimedia support or potentially have such active refresh rates that their VMs hit the cap on available CPU. To address these issues, you can look at Nvidia GRID and the Terradici APEX Offload Cards.
Nvidia is a graphics processing unit (GPU) that can enable superior 3-D rendering within a VM. APEX uses hardware processors to offload the cycles needed to manage the PCoIP protocol that VMware View uses to deliver virtual desktops.
Consider each of these points when fixing or evolving your own VDI implementation. Ultimately, the best advice I can offer is to engage a third party to assess your environment. Sometimes when you can't find your keys, a third party will point out that they've been on the table in front of you the whole time. VDI is the same way. You may think your environment is fine, and you may think you understand your users, but a third-party may add a different perspective for you.
It's important to hold VDI to a higher standard than your physical systems. This is a new technology that can elevate the user experience and reduce management. If it's not doing that, take a look at the latest and greatest tools and products that the industry has to offer in each of the key areas -- I think you will be glad you did.
Step one toward VDI: The assessment
What affects VDI network performance?
How to calculate VDI storage needs
Is GPU virtualization right for you?