The network storage wars have centered on iSCSI vs. Fibre Channel for so long that few have noticed the potential for Serial Attached SCSI (SAS) to disrupt the market even further.
Few, that is, except the buyers of storage equipment. InfoStor Magazine recently polled its readers on disk drive/array interface preferences and found an impressive 27 percent planning to invest heavily in SAS in the coming year. That still trails interest in SATA (37 percent) and Fibre Channel (32 percent), but it is impressive nonetheless for a technology still fresh out of the gate.
But can SAS replace Fibre Channel? That's the question Drew Robb asks on Enterprise Storage Forum in response to NetApp claims that its new FAS2000 appliances, and their ability to service high-performance SAS HDDs and high-capacity SATA disks, will drive a stake through FC's heart. While few people are willing to go that far, it's worth noting that SAS is likely to have a long shelf life, with the latest fabrics already optimized for 7200 RPM drives and other advancements.
With Fibre Channel firmly entrenched in the large corporate enterprise and iSCSI filling out the bottom, NetApp is clearly targeting the mid-level market for the FAS2000. The new FAS2020 and 2050, in fact, are suited for FC, SATA and SAS, but at 24 terabytes for the 2020 and 69 terabytes for the 5050, these clearly aren't for the local dentist's office.
One of SAS's advantages is its ability to provide tiered storage at low cost. This makes it suitable for maintaining easy access to day-to-day data, while still providing long-term storage for back-up and discovery. Of course, the same can be had by mixing Fibre Channel and SATA drives, but many will no doubt wonder why they should deploy a mixed bag of storage tiers where one single infrastructure is now available. A good white paper on the subject by Emulex' Bob Brencic is available here.
With so many different storage options available now, it's hard to imagine that any one technology will come to dominate any time soon. SAS certainly has a lot going for it, but there are very few instances in which one technology completely obliterates another. Heck, even this far into the jet engine age, there are still zeppelins flying over football stadiums.