IBM DS6000 Series manual Disk drives, Dense packaging, Host adapters, Switched FC-AL subsystem

The disk drives

The DS6800 controller unit can be equipped with up to 16 internal FC-AL disk drive modules, offering up to 4.8 TB of physical storage capacity in only 3U (5.25”) of standard 19” rack space.

Dense packaging

Calibrated Vectored Cooling technology used in xSeries® and BladeCenter to achieve dense space saving packaging is also used in the DS6800. The DS6800 weighs only 49.6 kg

(109 lbs.) with 16 drives. It connects to normal power outlets with its two power supplies in each DS6800 or DS6000 expansion enclosure. All this provides savings in space, cooling, and power consumption.

Host adapters

The DS6800 has eight 2 Gbps Fibre Channel ports that can be equipped with two or up to eight shortwave or longwave Small Formfactor Plugables (SFP). You order SFPs in pairs. The 2 Gbps Fibre Channel host ports (when equipped with SFPs) can also auto-negotiate to

1 Gbps for legacy SAN components that support only 1 Gbps. Each port can be configured individually to operate in Fibre Channel or FICON® mode, but you should always have pairs. Host servers should have paths to each of the two RAID controllers of the DS6800.

Switched FC-AL subsystem

The disk drives in the DS6800 or DS6000 expansion enclosure have a dual ported FC-AL interface. Instead of forming an FC-AL loop, each disk drive is connected to two Fibre Channel switches within each enclosure. With this switching technology there is a point-to-point connection to each disk drive. This allows maximum bandwidth for data movement, eliminates the bottlenecks of loop designs, and allows for specific disk drive fault indication.

There are four paths from the DS6800 controllers to each disk drive to provide greater data availability in the event of multiple failures along the data path. The DS6000 series systems provide preferred path I/O steering and can automatically switch the data path used to improve overall performance.

Here is a summary of the DS6800 major features:

￿Two RAID controller cards.

￿Two PowerPC 750GX 1 GHz processors and one PowerPC 750FX processor on each RAID controller card.

￿4 GB of cache.

￿Two battery backup units (one for each controller card).

￿Two AC/DC power supplies with imbedded enclosure cooling units.

￿Eight 2 Gbps device ports - for additional DS6000 expansion enclosures connectivity.

￿Two Fibre Channel switches for disk drive connectivity in each DS6000 series enclosure.

￿Eight Fibre Channel host ports that can be configured as pairs of FCP or FICON host ports. The host ports auto-negotiate to either 2 Gbps or 1 Gbps link speeds.

￿Attachment to up to seven (7) DS6000 expansion enclosures.

￿Very small size, weight, and power consumption. All DS6000 series enclosures are 3U in height and mountable in a standard 19-inch rack.

Chapter 1. Introducing the IBM TotalStorage DS6000 series 7