Small Business Server 2008 - Physical or Virtual?

One of the significant differences between SBS 2003 and SBS 2008 is that SBS 2008 now supports running a virtual environment and is supported running in a virtual environment. Before your eyes glaze over, let me try to explain. Virtualization is a huge buzzword these days, in the same vein as physical vs. cloud, but that's another topic. All through the beta process of SBS 2008, there was much discussion about if you could run SBS 2008 as a guest in a virtual box and if you could use SBS 2008 as a host for other virtual system. But before we break into the nitty-gritty, let me offer a brief glimpse why this is even an interesting discussion.

While I am no expert in virtualization, I did all of my testing for SBS 2008 in a virtual environment. I set up a nice big test box (one that I thought I'd be using to test Essential Business Server but opted later in the process to focus solely on SBS instead), loaded Windows Server 2003 64-bit, then loaded VMWare on top of that. Using VMWare as the virtualization engine, I build several instances of SBS 2008 servers, Vista and XP workstations, regular 2008 and 2003 servers, and ran a mish-mash of combinations of those boxes. From a testing standpoint, it was easy to switch back and forth between different builds of SBS so I could look at or test items that had changed. And having all of those "systems" on a single server box saved me office space, power consumption, etc., and made it relatively easy to take the entire setup to a different site for a real-time demo (although moving a PowerEdge 1900 server is not something I'd recommend doing on a regular basis, mind you).

OK, so virtualization made my testing life easier, big deal. What about using virtualization in a production environment? A couple of folks whom I highly respect have written the book on the topic for the SMB space, Dave Sobel and Karl Palachuk. They've also done a DVD seminar on the topic. Dave and Karl go into depth about the benefits of operating a virtual environment, but I'll briefly share my thoughts about virtualization. The ability to easily transport a virtualized system between physical hardware is one of the key points for me. You can take any VMWare virtual machine and copy it to another system, also running VMWare, and run it without any other changes. The same should hold true for Microsoft's Myper-V, but I have not worked with Hyper-V at all, so I cannot speak to it directly. Even if the host machine is completely different, say a Dell server versus an HP server, inside the virtual shell, the guest OS really doesn't care. It's up to the virtualization layer to translate the physical hardware into the virtual devices so the guest OS doesn't know that the physical NICs have changed, etc. But I digress, we're supposed to be talking about virtualization with SBS.

Back in September, Microsoft started rolling out their plans for support of SBS and virtualization. The first post appeared on the Official SBS Blog detailing how Microsoft would support SBS as a virtual guest. Shortly thereafter, the details also appeared on TechNet. Bottom line, there are a few key points to know about mixing virtualization with SBS 2008:

1. SBS 2008 cannot act as a host for other virtual machines.
   This actually makes some sense. So much stuff is going on with the SBS 2008 server that you really don't want to add trying to manage a virtual guest on top of that.
2. You can run SBS 2008 as a virtual guest, and Microsoft will support this configuration.
   This is the first time Microsoft has officially supported running an SBS environment as a virtual machine, but right now that's limited to using Hyper-V as the virtualization environment. So if you wanted to run both servers of an SBS 2008 Premium installation on the same physical box, you'd run them both as virtual guests on top of the Hyper-V host (although it also works well on top of VMWare from my experiences).
3. If you thought regular Microsoft licensing was confusing, wait until you try to undestand virtualization licensing.
   I'm not even going to try to make sense of how all the myriad combinations of licensing with respect to virtualization, because it makes my head spin, and I'd rather not muddy the waters for anyone else. Just realize that you should do your own research regarding proper licensing for any SBS 2008 virtualization implementations.

So, if you've been curious about virtualization in the SMB space, now is a good time to start learning about it, because there are a number of benefits and advantages. But like I've said time and time again, you really need to do your homework first. Just like not every business needs an SBS 2008 server, not every 2008 server needs to be virtualized. If you're not 100% solid on the technology, don't try to go out and implement it for a customer. Use it in your own house first, get familiar with it, and understand the issues surrounding the technology before trying to roll it in production for a client. You'll save yourself, and your client, a lot of headaches.

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