The IBM 7133 Model 020 is a rack-mountable package. The Model 020 provides ease of cabling by requiring no external cabling to complete internal strings of disks. It also improves availability in multi- initiator loops by providing bypass circuits that allow multiple planned or unplanned host outages. The Model 020 provides redundant power to all positions as standard.

The 7133 provides power and packaging for SSA disk drive modules. The Model 020 is designed to be mounted in a standard 19-inch rack and is four EIA units high. The Model 600 is a standalone unit similar in height to RS/6000 deskside systems.

The Models 020 and 600 provide slots for up to 16 SSA disk drive modules. These 16 disks are grouped together in fours. This is the same as the 7133 Models 010 and 500. The Models 020 and 600 provide circuitry that will automatically connect these groups of disk drives together. The automatic connection are made based on the presence of signals on the external connector. If there are signals present at one connector of a pair of connectors then these connectors will not be connected automatically. If there is not a signal at both of the connectors in a pair then these connectors will be connected automatically.

The 7133 Models 020 and 600 can be populated with three different SSA disk drive modules. The different capacities are 2.2GB, 4.5GB, and 9.1GB. The machine includes four 2.2GB disk drives as standard. These can be replaced by 4.5GB or 9.1GB drives at time of original order.

The 7133 Models 020 and 600 include three auto-docking power/cooling units. These provide redundant power to all sixteen disk drive module positions. These units may also be replaced by the customer.

The 7133 has selectable cable features of up to 25 meters long for attaching to an IBM High Performance 4-Port SSA Adapter in the attaching systems and for connecting to other 7133 subsystems. An SSA Fiber Extender is also available for use with optical fibers up to 2.4KM. The SSA Fiber-Optic Extender uses a 1310nm wavelength laser to drive multimode optical fibers. A minimum of two cables are required to properly install the 7133. More cables may be needed to achieve the desired performance and availability characteristics.