Here are my notes as I did some background research on StorMagic and their SvSAN solution to prepare for the sessions at Tech Field Day Extra / Cisco Live Europe 2016.
The company was founded in 2006 and is headquartered in Bristol, UK. Intel from the experts at El Reg also indicate that StorMagic has more than 1200 customers, for a total of 30000 licenses sold and 15000 unique sites. At the time of writing (1 year ago), the largest estate at a given US customer was approx 16 PB. There’s an interesting interview at Wikibon between Stu Miniman and StorMagic CTO Chris Farey here which was accidentally published a few days ago:
StorMagic offers a VSA solution that works starting from 2 nodes i.e. two physical servers. As you would expect, local storage on each of the nodes is leveraged. From version 5.2 and above you can also leverage local SSD drives for write caching (no mention about read caching) – also, it seems that you can select targets that will be accelerated. Yet another point I’m looking to understand better in terms of mechanisms.
The standard hypervisor features we’re used to nowadays (VMware HA, VMware vMotion and VMware DRS) are supported, so are the Hyper-V equivalents. Yes, smartly enough, it appears that StorMagic supports not only vSphere but also Hyper-V – fanboys from each side will certainly rejoice.
While starting at only 2 nodes, the solution is scalable to more nodes, but a limit is not given. The FAQ mentions that it is possible to mirror a pair of nodes with another, I’m interested to understand this better. To avoid for any potential split-brain scenarios, StorMagic recommends to have a third server to run a “Neutral Storage Host” used to identify the SvSAN cluster leader node. This server seems to be unrelated to SvSAN and apparently doesn’t requires an SvSAN VSA running on it.
The diagram above depicts the solution (including the Neutral Storage Host (highlighted as NSH). Stretched SvSAN clusters are also supported, a feature that can be interesting for some deployment scenarios. Considering the main market of StorMagic appears to be the retailer industry and any companies with lots of small locations, I can easily imagine an use case where an SvSAN cluster is stretched across multiple facilities within the same city. I hope StorMagic will provide us with use cases.
The requirements in terms of compute (RAM, CPU) are modest and will likely minimally impact the cluster performance. The licensing model itself is intriguing (spec sheet and FAQ seem to indicate different information) and I hope to gain more clarity on this. From what I was able to read, listen and watch, this solution seems to be what the Czech call “hodně muziky za málo peněz”, which roughly translates as “a lot of music (or features) for a handful of money”.
I’m curious to understand what markets/use cases StorMagic is targeting, also how they position themselves against their competitors. Speaking about competition, I’m not certain that I would call VMware a competitor, considering that VSAN, although leveraging local storage, is built on a totally different approach of object storage which allows to define per-VM policies and aims the data center. Nutanix also seems to be targeting a much different market/use case, where the emphasis is put on linear (and massive) scalability, also aiming for the data center rather than the small branch office.
I hope to learn more in Berlin at TFDx!