Hardware speed selection behind a disk array controller

摘要

A system has a plurality of enclosures. Each enclosure has two enclosure services modules. Each enclosure services module has an IN port and an EXPANSION port. Each enclosure services module is able to determine the data rate of incoming data and check the validity of this data. If the data rate is other than what the enclosure services module is set for, the data rate of the enclosure services module is changed to that of the incoming data. In the system, there are a disk array controller having a first channel and a second channel. The first channel is formed in sequence from a disk array controller to a first enclosure services module of a first enclosure and between first enclosure services modules of successive enclosures to a last enclosure. The second channel is formed in reverse sequence from the disk array controller to the second enclosure services module of the last enclosure and between second enclosure services modules of successive enclosures to the first enclosure.