One of the major topics we discussed in last weeks episode of The In Tech We Trust Podcast was VSAs vs VSAN. And I think it’s a pretty interesting topic.
VSA’s Commoditize the Hypervisor
The way I see it, the VSA approach offers more choice, more competition, and is ideologically superior.
I’m a huge believer that competition drives innovation, as well as value for customers. Not only are there a ton of VSA products to choose from, but VSAs commoditize the hypervisor. I mean…. as long as a VSA vendor supports their VSA on multiple hypervisors, there’s absolutely no reason why a VSA running on top of vSphere can’t replicate with a VSA running on top of Hyper-V. And if you’re on vSphere today, you can absolutely switch over to Hyper-V tomorrow (or vice-versa). And the notion that the hypoervisor no longer matters (i.e. its commoditized) is a great idea in my book – it’s the next natural step from commoditization of hardware.
But VSAN has Advantages
That all said, I recognise that compared to a kernel-based storage controller architecture like VMware VSAN, the VSA approach has some challenges. After all, VMware VSAN can benefit from being written by guys that know vSphere and its roadmap inside out. And…. in general, tightly integrating something at the kernel-level often brings stability and performance benefits. So I see some obvious short-term benefits to the VSAN approach.
But VSAN is Hypervisor Lock-in
But…. VSAN locks customers in to vSphere – and no matter what anybody says, lock-in is never a good thing. Sure, there can be short-term benefits. But unless you’re a fanboy who’s intravenously taking vendor kool-aid…. in the long run, lock-in should be avoided at all costs!
VSAN is No Different To Buying a Traditional Array
For me, the VSA approach is the right approach. Buying into VSAN is only one small step away from buying traditional storage arrays where the software and hardware are locked to each other. With VSAN the storage intelligence is locked to the hypervisor – which is pretty much the same as with traditional arrays. Seriously, what’s the difference between welding VSAN to the vSphere kernel, versus welding storage controller intelligence to hardware – a la VMAX, VSP, 3PAR….?!?!?!
As good as VSAN might be, it’s the wrong approach.
For me, when I last looked at EMC ScaleIO, I thought I was looking at a technology that could take the market by storm. Fingers crossed EMC throws its brightest minds at it!