Due to the amazing power of computers, computers are widely used to implement diversified tasks such as data processing tasks, amusement-related tasks or communication tasks. With the increasing development of digitalized generation, the data storage density for the conventional data storage media might become unsatisfactory soon for receiving and storing a great amount of data. For dealing with such a problem, a single data storage medium with a very large quantity of storage capacity or a plurality of data storage media are used in a computer system. Conventionally, data stored in a data storage medium are read via a disk drive that is operated mechanically. Therefore, the operating speed of the disk drive likely fails to catch up with the high processing speed of the central processing unit (CPU). For matching the operating speed of the disk drive and the processing speed of the central processing unit, a configuration of RAID (Redundant Array of Inexpensive Disk) is proposed. In the RAID configuration, multiple disk drives are used to store the same data in order to increase the data transfer rate and data safety. In a case that one of the multiple disk drives has a breakdown, the lost data can be restored according to an interactive encoding technology among the disk drives.
Typically, the disk drives communicate with the computer system via a host bus adapter (HBA). Since one host bus adapter can only link thereto a limited amount of disk drives, two or more host bus adapters are required for serving a larger amount of disk drives. All host bus adapters are electrically connected to a miniport driver stack layer, which serves as a small computer standard interface (SCSI) between the disk drives which link to the host bus adapters and the computer system. Since the operations of these host bus adapters are independent from each other, the disk drives can only be driven by the host bus adapters linking thereto. If any of the host bus adapters has a breakdown, the disk drives which link to the damaged host bus adapter cannot participate in the RAID configuration, so the performance of the RAID configuration is largely reduced. For example, if one host bus adapter has been idle for a long time and enters a sleeping mode, other host bus adapters might have problems in synchronization.