A few months ago, I was quoted in a video saying something along the lines of, "You need a client hypervisor like...
you need a hole in your head!" (In other words, I didn't think that client hypervisors were a good idea.)
My reasoning was that in order to use a client hypervisor effectively, there is so much "work" that you have to do that by the time you are finished, you might as well have just saved all the effort and gone on using your traditional, non-client hypervisor-based desktop environment.
For example, if you use a client hypervisor, you still have to manage your Windows image. You still have to install and test patches and updates, and you still have to test and maintain applications. If you're going to do that, why bother? Why not just use a traditional patch management system, like Altiris or Microsoft Systems Center Configuration Manager (SCCM)?
Another supposed advantage of client hypervisors is that it allows you to encrypt your client hard drives. But last time I checked there were tons of solutions on the market for that. So, really, why bother with a client hypervisor?
Another benefit of client hypervisors is administrators can trigger a "kill pill" to remotely disable a client virtual machine. But again, there are plenty of existing utilities that can do that.
Ease of backup is another feature touted by the client hypervisor vendors, but there are lots of backup tools out there. You don't need a client hypervisor for that.
Client hypervisors can allow a single virtual machine image to run on multiple different types of client machines, but only if you build separate driver packs or if you "overbuild" the drivers that you embed into your master image. But that, too, is something you can do with Windows natively that doesn't require a client hypervisor.
My point was that with all the traditional Windows desktop management tools out there, who needs a client hypervisor? Why not just overbuild your drivers and deploy images with SCCM, then use some kind of backup software, disk encryption and remote kill software. If you have all that, why do you need a client hypervisor?
"Yes! That is exactly the point! Thank you for making my case!" This is what someone told me after seeing that video. Ironically, the person who said this works for Virtual Computer -- a company whose entire business is built around client hypervisor technology. He went on to explain that I proved his point for him. Yes, you can use traditional Windows image management, plus a traditional Windows image deployment and patch management tool, plus an online backup tool, plus a full disk encryption tool, plus a remote security kill pill tool. Or you can get all of those features just using one client hypervisor product.
Now I get it. I was envisioning client hypervisors as an extension of desktop virtualization. But that's not right. Client hypervisors are simply about using desktop virtualization as a tool to manage the traditional desktop issues. They're not about virtualization at all.
As a funny conclusion to this realization, I met a customer of one of the client hypervisor vendors and in response to my quote about needing a client hypervisor like you need a hole in your head, she said, "If I didn't have my client hypervisor, I would put a hole in my head."
ABOUT THE AUTHOR:
Brian Madden is an independent industry analyst and blogger, known throughout the world as an opinionated, supertechnical desktop virtualization expert. He has written several books and more than 1,000 articles about desktop and application virtualization. Madden's blog, BrianMadden.com, receives millions of visitors per year and is a leading source for conversation, debate and discourse about the application and desktop virtualization industry. He is also the creator of BriForum, the premier independent application delivery technical conference.