Server Administrator Storage Management 8.2 User’s Guide

Most operating systems do not read and write data directly from the disks, but instead send read and write instructions to a controller. The controller is the hardware in your system that interacts directly with the disks to write and retrieve data. A controller has connectors (channels or ports) which are attached to one or more physical disks or an enclosure containing physical disks. RAID controllers can span the boundaries of the disks to create an extended amount of storage space — or a virtual disk — using the capacity of more than one disk.

Controllers also perform other tasks, such as initiating rebuilds, initializing disks, and more. To complete their tasks, controllers require special software known as firmware and drivers. In order to function properly, the controller must have the minimum required version of the firmware and drivers installed.

Storage Management supports different types of controllers. If your system has a supported controller, the controller is displayed by expanding the Storage object in the System tree view in the GUI. You can select the controller to display tabs for executing controller tasks and viewing controller properties.

Different controllers have different characteristics in the way they read and write data and execute tasks. It is helpful to understand these features to most efficiently manage the storage. The following sections describe the supported controllers and their features.