Method for accessing target disk, system for expanding disk capacity and disk array

摘要

The present invention discloses a method for accessing a target disk and a system for expanding disk capacity. A processing unit of a master disk array sends a command or data to a PCIe switching unit of the master disk array upon receipt of the command or data; the PCIe of the master disk array sends the received command or data to a control unit in a corresponding disk array according to an address of a target disk indicated in the command or data; the control unit in the corresponding disk array sends the received command or data to the target disk that is directly connected to the control unit. The present invention also discloses a master disk array and a slave disk array.