Windows Server 2012 : A complete virtualization platform (part 5) - Improved Live Migration - Live Migration using a shared folder

Experiencing SMB share hosting

Being an infrastructure consultant for the better part of my IT career has included some very deep and thought-provoking discussions about the best ways to accomplish certain goals. Whether the dialogue was comprised of topics such as virtualization, storage, or applications, the common theme throughout was clearly protection of one’s digital assets and data. Everyone wanted to design a cost-effective (operative term) disaster recovery solution for their workloads without affecting performance or user impact; however, we all know that you get what you pay for when disaster recovery solutions are concerned.

It was recently told to me that the number two reason for a company implementing a virtualization strategy is disaster recovery. That makes sense to me; however, most of the underlying infrastructure required for a physical server disaster recovery environment is still required in the virtualized world. We still needed the replication of our data through underlying storage. We still needed the like “cold spare” hardware to pick up where our primary servers left off. Don’t get me wrong—these solutions are fantastic, but in the end, are quite costly. There needed to be a way to ensure that the smaller IT budgets in the world did not fall to the bottom of the “you get what you pay for in disaster recovery” bucket.

Enter Windows Server 2012. In my opinion, this is truly the first “cloud-ready” piece of software that I have seen capture the entire portfolio of cloud readiness features. Shifting the focus to the mobility of workloads (which is the basis for improving upon current disaster recovery functionality) was clearly a theme when designing this software. The ability to never have to turn your VM off, regardless of scenario, is the holy grail of disaster recovery.

So of course, being an engineer, I wanted to play with this stuff. After installing a couple of Hyper-V and file servers, I decided to test an SMB share hosting my VM files. As generally non-complex as that sounds, it was quite cool to see my associated virtual hard disk (VHD) be linked to a network path.

I decided to see what I could do with this share, and without knowing, stumbled upon an improvement to Live Migration. In Windows Server 2012, you can seamlessly migrate a VM hosted on an SMB file share (This needs to be SMB 3—currently Windows Server 2012 only) to any other host in the same domain (given share permissions). I chose to move my machine to another host of mine, and before I was able to Alt-Tab to the documentation and back, my VM had already moved. What I forgot about at the time of migration was that I never did any prerequisite storage configuration on any of the host machines, which made the whole experience much more exciting. It just worked. I couldn’t wait to couple this with the other optimization technologies built in to the operating system (de-duplication and compression) for some real gains.

Then, my engineering mind went to the next obviously logical step: “Okay, how can I break this thing?” The demos I had seen on this had shown Live Migration with workloads such as pings and file copies. That just didn’t do it for me … I wanted my VM to host streaming video. With my setup in place, I streamed not one, but two video files to different clients on my network and monitored them. One stream was a simple AVI file hosted on a file share. The other was a high-definition video file hosted by a server-side transcoder that was streaming to my laptop. I also had a ping going just for kicks. The CPU had settled around 30 percent on the VM once both videos were going, so I was interested to see what the results would be. Once Live Migration kicked in, I was watching for any blip or interruption to the video files, with no result. The best interruption, almost amusingly, was a dropped ping in my command prompt. Being overly satisfied with my little demo environment, I proceeded to watch the rest of my movie.