A storage network system includes a storage device including a volume for recording data, and a network connection device, and a host including a device for reading/writing data from/into the volume through a network. The host includes a security inspection program for performing security inspection of data communicated through a network and generating an inspection log including a result of the security inspection, inspection log acquisition means for acquiring the inspection log generated by the security inspection program whenever occasion demands, and copy command issuing means for issuing a copy command to copy data from the volume to another volume when there is no abnormality in the content of the inspection log concerning the volume.