PURPOSE: To let a service processor acquire the information of a fault occurred in a channel processor and its lower order device by designating a storing destination storage area at the time of the storage of the fault information in plural fault information storage areas, and a reading destination storage area at the time of the read-out of the stored fault information.

CONSTITUTION: When the new fault arises in the channel processor 1 while the service processor (SVP) 3 reads the fault information stored in a certain fault information storage area 101 to 108 by a fault information reading means 31, the fault information is written by a fault information storing means 120 to the fault information storage area different from the fault information storage area designated by a designating means 100. Then, the fault information of the fault information storage area to which the fault information was newly stored is read out after the finish of the read-out by the SVP 3. Thus, the fault information of the channel processor and the lower order device of the channel processor can be collected during a period including fault restoration processing.