Back in September I wrote an article called “What is Hyper-Convergence?” In that article, I explained what this concept was and I shared my thoughts on the positives and negatives of this kind of deployment of Hyper-V, vSphere, or other virtualization/cloud platforms. In this article, I will explain what I believe to be Microsoft’s viewpoint on hyper-convergence.
The traditional deployment of a vSphere or Hyper-V farm has several tiers connected by fabrics. The below diagram shows a more traditional deployment using a storage area network (SAN). In this architecture you have:
In the Hyper-V world, we are able to do a software-defined alternative to a SAN called a Scale-Out File Server (SOFS), where:
But for the most part, the high-level architecture doesn’t really change:
In the world of hyper-convergence, we simplify the entire architecture to a single tier of servers/appliances that run:
I say “simplify” but under the covers, each server will be running like a hamster on a wheel … on an illicit hyper-stimulant.
Hyper-convergence is a topic that has only been getting headlines for the last year or so. This is mainly thanks to one vendor that is marketing like crazy, and VMware promoting their vSAN solution. I had not heard Microsoft share a public opinion about hyper-convergence until TechEd Europe 2014 in October.
The message was clear: Microsoft does not think hyper-convergence is good. There are a few reasons:
This is why Microsoft continues to push solutions based on a storage tier and a compute tier, which are connected by converged networks, preferably leveraging hardware offloads (such as RDMA) and SMB 3.0. The recently launched Dell/Microsoft CPS is such a solution.
In my opinion, Microsoft is right. I don’t think hyper-convergence can scale well without making sacrifices in terms of performance and complexity. I question the economics of the concept – not just in terms of scale-out, but also the cost of some of the hardware solutions out there makes purchasing a Dell Compellent or a NetApp SAN look affordable!