Reduction of data processing capacity attributable to the occurrence of a failure is prevented by promptly identifying the failure location.A storage apparatus includes a plurality of expanders connected to storage media storing data sent from a host system, and a controller for controlling the expanders, wherein the controller sends a failure detection command to the plurality of expanders; the plurality of expanders store the command in their own storage units; and if one expander from among the plurality of expanders detects a failure in another expander immediately following and connected to the one expander, the one expander reads the command stored in a storage unit for the one expander and sends a response including failure detection information corresponding to the command to the controller.