There has been so much hype around and talk about VDI that the more basic questions have almost been forgotten: is it ready for everyday production use, and if so, how? Many different strategies are promoted by vendors and many different technologies compete for attention. If one could only do a VDI project just for learning what works and what does not! Almost as good as that is hearing from others what worked for them, and I provide just that in my Synergy Geek Speak session SYN502: Persistent VDI: real-world solution or empty promise?

I will talk about a real 650 seat XenDesktop project, what went well, what did not and how to do it better next time.

I begin with questions every business needs to answer before starting such a project:

- Why VDI?
- Which is my strategic platform: TS, VDI, PCs?
- Which platform do we put people on that cannot (for some reason) work on the preferred platform?
- What criteria do I use to decide which users get which device?

When these questions are answered, the real project work starts: choosing a VDI software (XenDesktop in this case) and sizing the platform.

Green crossroad by unicoletti under CC

Essential questions at this stage are:

- What kind of servers do we need?
- How much CPU power, how much RAM, etc.?
- How many servers do we need to buy?

A big factor of uncertainty with VDI has always been the “storage problem”, which is a problem because difficult questions must be answered:

- Where do we put the VMs?
- Shared or local storage? Expensive or cheap?
- How do we make sure that I/O performance is high enough?
- How to keep the space requirements at reasonable levels?

This all depends, of course, on the answer to:

- Pooled or private?
- Do we treat the virtual desktops as a user’s personal device or do we reset them as soon as the user logs off?

This question goes hand in hand with the question of how to get applications to the VMs. The possibilities are nearly endless!

I could go on and on and on, but then there would be no point in coming to my session, right?

So, see you at Citrix Synergy on May 22nd at 8:30am in “SYN502: Persistent VDI: real-world solution or empty promise?” right before the Synergy keynote!

Helge Klein is an independent consultant and developer and has worked on Citrix projects for various large German corporations. He architected the user-profile management product sepagoPROFILE, which is now available as Citrix Profile Management. Helge is also the author of the popular open source tool SetACL. He publishes a blog at