A computer system includes a host computer; a storage system for obtaining a snapshot, at a specific point in time, of a data volume, storing data written to the data volume after the specific point in time as a journal, and applying the journal to the snapshot for data recovery; and a management computer. In the computer system, the management computer instructs the storage system to determine whether data at a recovery point after a recovery point of the latest snapshot can be recovered within a specific period of time and to apply, if it has been determined that the data cannot be recovered within the specific period of time, a journal to the latest snapshot to update the latest snapshot to a new snapshot in such a manner that the data can be recovered within the specific period of time