IBM DS8000 manual Frames, Base frame

2.1 Frames

The DS8000 is designed for modular expansion. From a high-level view there appear to be three types of frames available for the DS8000. However, on closer inspection, the frames themselves are almost identical. The only variations are what combinations of processors, I/O enclosures, batteries, and disks the frames contain.

Figure 2-1is an attempt to show some of the frame variations that are possible with the DS8000. The left-hand frame is a base frame that contains the processors (eServer p5 570s). The center frame is an expansion frame that contains additional I/O enclosures but no additional processors. The right-hand frame is an expansion frame that contains just disk (and no processors, I/O enclosures, or batteries). Each frame contains a frame power area with power supplies and other power-related hardware.

Rack	Cooling plenum
power	disk enclosure pair
control
	disk enclosure pair
Primary	disk enclosure pair
power	disk enclosure pair
supply
	eServer p5 570
Primary
power	eServer p5 570
supply
Battery
Backup unit	I/O	I/O
Battery	Enclosure 1	enclosure 0
Backup unit	I/O	I/O
Battery
	Enclosure 3	enclosure 2
Backup unit

Fan	Cooling plenum		Fan
sense	disk enclosure pair		sense
			card
card
	disk enclosure pair
Primary	disk enclosure pair		Primary
power	disk enclosure pair		power
supply			supply
	disk enclosure pair
	disk enclosure pair
Primary	disk enclosure pair		Primary
power			power
supply	disk enclosure pair		supply
Battery
Backup unit	I/O	I/O
Battery	Enclosure 5	enclosure 4
backup unit	I/O	I/O
Battery
	Enclosure 7	enclosure 6
Backup unit

Cooling plenum

disk enclosure pair

disk enclosure pair

disk enclosure pair

disk enclosure pair

disk enclosure pair

disk enclosure pair

disk enclosure pair

disk enclosure pair

Figure 2-1 DS8000 frame possibilities

2.1.1 Base frame

The left-hand side of the base frame (viewed from the front of the machine) is the frame power area. Only the base frame contains rack power control cards (RPC) to control power sequencing for the storage unit. It also contains a fan sense card to monitor the fans in that frame. The base frame contains two primary power supplies (PPSs) to convert input AC into DC power. The power area also contains two or three battery backup units (BBUs) depending on the model and configuration.

The base frame can contain up to eight disk enclosures, each can contain up to 16 disk drives. In a maximum configuration, the base frame can hold 128 disk drives. Above the disk enclosures are cooling fans located in a cooling plenum.

20DS8000 Series: Concepts and Architecture