No I think that they are using drives with a specific purpose and do not need enterprisey functions. I think they mean drives that are the quality of the WD bl

No I think that they are using drives with a specific purpose and do not need enterprisey functions. I think they mean drives that are the quality of the WD black drives, it looks like them in the one picture. The types of drives that you might build a Hadoop cluster with knowing that you will be replacing 1-2 drives per 100 every month. These drives (unless I misread) do not need to be hotswappable nor any other specialized setup. I would bet they are JBOD and directly attached with minimal controllers. If one drive per tray is powered on at a time then there is no RAID running across that tray... As a point of comparison an expensive enterprise drive that you might see in a Netezza appliance costs many times more and has specialized firmware to work in a specific application, with certain RAID controllers at specific firmware setings. From experience I do not think that they are much more reliable - they are specific to the appliance, or in some cases like Aerospike required SSDs specific to a software requirement. This storage design is stripped bare - the HDDs are off for most of their lifetime. I guess the biggest stress on them is spinning up and spinning down. They must focus on precise temperature/humidity control as it might be as much of a problem to have the drives too cold as too hot.