When NetApp purchased Spinnaker I was startled, as I could not understand the reason behind the purchase. Spinnaker, like Panasas, could have been a viable company, but they were both late to the marketplace, and could not get the market acceptance that the Internet boom provided both EMC and NetApp. But Spinnaker had identified a few niche markets, as has Panasas. Additionally, the Spinnaker technology was based on the Andrews File System & the NetApp system is based on BSD. So they really could not be easily integrated. In my humble opinion, Panasas would have made more sense to purchase from a technology point of view for NetApp. So, I was very interested in reading this article by Chris Mellor over the weekend.
Gigabit Ethernet clustering just doesn’t give you the performance and future headroom that Infiniband does.
Anderson says: “NetApp uses Infiniband to cluster two nodes. When NetApp bought Spinnaker it then made a mistake. It tried to add features out of the Spinnaker product into ONTAP. But clustering can’t be done that way; it has to be in the DNA of the system. NetApp’s approach didn’t work. Two years ago NetApp reversed direction. Dave Hitz (NetApp CEO) announced that Data ONTAP GX is a Spinnaker foundation with NetApp features added to it.”
Anderson added this comment: “(Data ONTAP GX) is namespace organisation. It’s not clustering. It’s RAID behind the veil and can still take eight hours to rebuild a disk. They’ll be performance problems downstream. It’s a bandaid. It’s a total kluge.”
With Isilon file data and parity data is striped across up to 9 nodes. A failed disk can be re-built in 30 minutes to an hour. In effect, Isilon’s striping technology renders RAID redundant.
Anderson says suppliers like Acopia ‘do it in the switch layer. It’s not rich, it’s lightweight.’ Again there will be performance problems downstream.
A virtualised pool of NAS resource requires the NAS nodes to be clustered for smooth performance scaling. It also requires N + 2 protection so that the system can recover from two failed disks and not just one. (NetApp’s RAID DP provides protection against two disk failures.)