The Ugly Truth about Type-2 Client Hypervisors
When I
wrote about type-1 client hypervisors, I made it very clear that I am biased towards them. I reiterate that again, so as to avoid getting grilled in the comments section below.
Don't get me wrong. I have VMware Fusion on my laptop and use it on a daily basis, but using a type-2 client hypervisor enterprise-wide? No thanks!
The idea behind desktop virtualization is to make management of desktops (among other things) easier. When using a type-2 client hypervisor, you double, triple or quadruple the number of OSes that you have to support. So instead of a user calling and saying, "I am having an issue with my desktop," they will call and say, "I am having an issue with my desktop; oh, by the way, I am also having a weird connectivity issue with VM2 and VM3 needs patching." Do you really want to do that?
I have been at conferences where speakers have touted type-2 client hypervisors as perfect for BYOPC, because you offload the support of the underlying OS to the manufacturer. My reaction is always: "Really? Seriously, you just said that?" So if a user calls up with an issue, you will tell them to call the manufacturer? Well in my book, that does not fly in the corporate world. While the VM you provided them is working, the OS needed to launch that VM is having an issue. Therefore the user cannot get to the VM and is not productive. How long do you think it will be before an executive calls in and asks what kind of a messed up support model you have?
To add insult to injury, Microsoft developed MED-V, so now you have a way of centrally managing all the VMs running on your desktop. Instead of addressing the issue, let's quadruple the numbers of OSes, and give an additional management console to manage them all. Now you are tasked with keeping all your VMs patched, AV software updated. Oh, and you get a new management tool that will end up being part of SCCM at some point. No way!
Now aside from my obvious dislike for type-2 in the enterprise, let's see... there's also:
- Reliance on parent OS rendering the VM at the mercy of that OS. If that instance of the OS does not work properly, your VM won't run.
- Performance is not on par, since the VM is sharing resources with the underlying operating system.
- Security is also tied to a certain extendt to the parent OS.
- Management and support of a new instance of an OS.
So, am I a fan of XP-mode in Windows 7? Absolutely not. Well, not for the masses at least. The excuse that we have applications that don't work on 64-bit Windows 7 and so we love the ability to serve up an application seamlessly into Windows 7 while it runs in XP, my answer to all that is: Instead of localizing the application to each user, deploy it using Terminal Server and XenApp. They've added the seamless application for ages and if you need apps that work on XP, you can publish those. Or, they might work on Windows Server 2003, so that is easier, smarter and better to manage.
In my book, type-2 client hypervisors are utterly useless in an enterprise deployment. Still, I would love to get your perspective on things and maybe, just maybe, I really am missing something here. I'd love to learn. Thoughts?
Posted by Elias Khnaser on 04/14/2011 at 12:49 PM