Disk array device and path failure detection method thereof

A disk array device including a first control unit connected to a switch device connected to a host system via a first path through which data is transmitted and received, a second control unit connected to said switch device via a second path through which data is transmitted and received upon a failure, a memory for storing control information, and a storage apparatus for storing data transmitted from said host system;

• wherein said second control unit has a transmission unit for transmitting a first command to said first control unit via said second path and said switch device and said first path, and a determination unit for determining that a failure has not occurred in the communication between said second control unit and said switch device when there is a response to said first command.

A path failure detection method of a disk array device including a first control unit connected to a switch device, which is connected to a host system, via a first path through which data is transmitted and received, a second control unit connected to said switch device via a second path through which data is transmitted and received upon a failure, a memory storing control information, and a storage apparatus storing data transmitted from said host system comprising:

• a first step for storing control information used in the communication between said first control unit and said host system in said memory;
• a second step for transmitting a first command to said first control unit via said second path and said switch device and said first path;
• a third step for determining whether a failure occurred in the communication between said second control unit and said switch device based on a response to said first command.

A disk array device including a control unit connected to a host system via a path, a memory for storing control information, and a storage apparatus storing data transmitted from said host system;

• wherein said memory stores control information used in the communication with said host system;
• and
• wherein said control unit has a transmission unit for controlling the transmission and reception of data between said host system and said storage apparatus conducted via said path and transmitting a command to said host system via said path based on the control information used in said communication stored in said memory, and a determination unit for determining whether a failure occurred in the communication between said host system and said control unit based on a response to said command.