Overcoming Network Challenges with Virtual Desktop Infrastructure (VDI)
Gartner is predicting that hosted virtual desktop deployments will reach 15 percent of professional desktop users by 2014. Reading David White’s recent article at CIO.com – The Growing Importance and Network Impact of VDI – got me thinking about virtualization at the desktop level and the network challenges it creates.
Storage is at the heart of server virtualization and it’s no different for VDI. When you centralize virtual desktops, everything that occurs without VDI is compounded and can stress the storage infrastructure. I/O storms can occur from simple things like user log in, boot up, and shut down. User experience will degrade quickly if the storage subsystem can’t handle peak I/O requirements. VMware recommends in their VMware View 5 Performance and Best Practices white paper to use SSDs for virtual disks to achieve the best performance. Storage arrays that take advantage of SSD can support upwards of 80,000 IOPS if done correctly. Jumbo frames, an isolated network, and plenty of bandwidth to the storage array can also make a difference if you’re using a network protocol for storage,
The WAN itself is not the challenge; the culprit is low bandwidth and high latency. Bandwidth is not cheap and lots of things are riding the WAN back to the data center, where in most cases, the VDI environment is also located. So the challenge is sizing the WAN to accommodate the added bandwidth for VDI. In some cases, there is a drop in WAN utilization with virtual desktops in the data center with the core applications. You won’t know for sure, so plan for the increase. A WAN optimization product like a Riverbed Steelhead appliance works well here.
Other not-so-technical areas can also make deploying VDI challenging like software licensing and upfront CAPEX. While Microsoft improved their licensing around virtualized environments, the OS still comes with a cost. Additionally, upfront costs for building a VDI environment can be quite high. This can deter companies from deploying VDI, especially in this economy and when ROI is hard to identify.
Every company will have different challenges. A good VDI environment can offer agility for desktop services and applications, better security and compliance, standardization, and better management. You can overcome hurdles by planning, and putting the right solutions in place.