This model was a disk storage server used in the Data Centre up until 2012.

Each tray contains a hard disk drive (see the 5TB hard disk drive on the main disk display section - this actually fits into one of the trays). There are 16 trays in all per server. We have hundreds of these servers mounted on racks in the Data Centre, as can be seen.

We use disks for short-term storage, and as a buffer to hold data while writing it to tape.