Patent attributes
A proposal is made of a file management system and method capable of reliably deleting unnecessary data. In a file management console and method for reading or writing data of a file from or in a first volume, which is provided by a storage device, in response to a request sent from a host computer, one snapshot or multiple snapshots that relate to the first volume and can be updated are created. In response to an externally issued designated file deletion command, a designated file is deleted from all of the first volume and snapshots or part thereof specified in the deletion command. At this time, the data items of the designated file in the first volume and/or snapshots from which the designated file should be deleted are overwritten with invalid data. Moreover, pieces of management information on the designated file are changed to a reference-disabled state.