Abstract: A disk array control device includes a determination unit that receives a reading request in which blocks of connected disk devices are designated, determines whether or not writing has been performed in the designated blocks after initial setting, a) outputs data all of which is a predetermined value when the writing has not been performed, and b) reads and outputs data in the designated blocks when the writing has been performed.

Abstract: Disclosed is a data preservation processing device which effectively realizes data preservation processing on an occurrence of a bit error. The data preservation processing device includes: a memory monitoring and detection unit which detects a memory being in an abnormal state, the memory being included in a controller which is communicably connected with a storage device and temporarily storing data which is inputted in the storage device; and a data protection unit which changes a write policy concerning the storage device to write-through when the memory monitoring and detection unit detects the memory being in the abnormal state.