When deploying or evaluating the continuing viability of a VDI implementation, the discussion undoubtedly turns to the selection of the best hypervisor on which to host your users' desktops.
Accurately analyzing your virtual desktop infrastructure (VDI) requirements is the key to selecting the appropriate hypervisor to support your environment. The main virtualization hypervisors are Microsoft Hyper-V, VMware vSphere and Citrix XenServer, plus the open source KVM, but your choice depends greatly on your specific environment's requirements and long-term goals.
Let's take a look at the technical, financial and organizational considerations for choosing a hypervisor for VDI, whether you are implementing a new project from scratch or considering making a change to your existing VDI environment.
Analyze VDI requirements
Choosing a VDI hypervisor before you know your VDI requirements is like building a house without counting your children first; you need to know how many bedrooms you need in your new home.
As with all major IT projects, a thorough analysis of IT and end-user requirements is the only logical way to start your evaluation of hypervisors. Engage an experienced IT project manager for assistance with the requirements-gathering and analysis phase of selecting a VDI hypervisor. Build a requirements matrix and use it to evaluate the features, capabilities and capacity of the hypervisors under consideration.
Know what you use, and use what you know
Carefully consider any hypervisors already running in your infrastructure. Acquisition costs, labor, training and testing can make up 50% or more of the ongoing costs to install and support a VDI hypervisor. By choosing a VDI hypervisor that your organization already supports for other software platforms, you take advantage of existing tribal knowledge and expertise that can save your company money in the long run. You don't need to only consider the hypervisors already running in your infrastructure, but you should remember labor, training and testing costs that will factor into the final financial evaluation of selecting a VDI hypervisor.
Of course, no discussion of IT software is complete without taking into account the cost of licensing the VDI hypervisor and the virtual machines (VMs) running on that hypervisor. Explore any existing software licensing agreements that you could use in your VDI environment.
If you already have hypervisors in your development or production environment, it might be financially advantageous to piggyback your VDI hypervisor purchases onto an existing hypervisor license agreement. Also, consider not just the initial cost of acquiring the VDI hypervisor but also factor in the licensing costs of each VM. VM licensing costs are a commonly overlooked aspect of VDI implementations and ongoing support. In fact, the initial acquisition costs of your VDI hypervisor will likely pale in comparison with your VM licensing costs.
Refer back to your requirements to recognize your VDI management needs and verify that your hypervisor platform offers tools that can easily integrate with your existing monitoring infrastructure. Remember that VDI, once in production for end users, is a mission-critical component of your infrastructure. If users cannot access their virtual desktop, they will not be able to perform their jobs. Having workers idle due to a VDI outage can cost your company thousands of dollars in lost productivity and opportunity costs. Effective management tools are your insurance policy against downtime that can quickly obliterate any budget savings offered by VDI in the first place.
Expandability and future-proofing your VDI
Lastly, be sure to consider your long-term requirements when selecting a VDI hypervisor. If you have specific VDI requirements that are not currently available from Hyper-V, ESXi or XenServer, explore the product roadmap for each hypervisor to determine which one offers your company the best path as your requirements change over time. Be especially vigilant when considering capacity requirements into the future. Your VDI hypervisor must not only be able to support your current volume of users, you must also be able to expand it to support more and more users.
Keeping these basic ideas in mind can help ensure that your next VDI hypervisor is your last VDI hypervisor.