HP Array Controller HSG V8.7 Software - Manual (Page 31)

General Description 1–7
The HSG80 Array Controller
Your controller is the intelligent bridge between your host and the
devices in your subsystem. As Figure 1–2 illustrates, it bridges the gap
between the host and its storage subsystem.
Figure 1–2 A Host and Its Storage Subsystem
The controller is an integral part of any storage subsystem because it
provides a host with high-performance and high-availability access to
storage devices.
The controller provides the ability to combine several ordinary disk
drives into a single, high-performance entity called a storageset.
Storagesets are implementations of RAID technology, which ensures
that every unpartitioned storageset, whether it uses two disk drives or
ten, looks like a single storage unit to the host. See Chapter 3,
“Creating Storagesets,” for more information about storagesets and
how to configure them.
From the host’s perspective, the controller is simply another device
connected to one of its I/O buses. Consequently, the host sends its I/O
requests to the controller just as it would to any Fibre Channel device.
From the subsystem’s perspective, the controller receives the I/O
requests and directs them to the devices in the subsystem. Because the
CXO6233B
Host
Storage
subsystem
Controller
Hub