Patent ID: 7587627

Claim:
In a computer system including: a first computer which executes a data base management system, a first storage system coupled the first computer and including a cache memory, a side file memory, a first disk apparatus and a second disk apparatus, a second storage system coupled to the first storage system via a remote copy line, a second computer coupled to the second storage system, a remote copy managing method for managing two copy modes, either a first copy mode or a second copy mode is used for a remote copy to transfer update log data between the first storage system and the second storage system via the remote copy line, the update log data is update history information to update database in the database management system, comprising the steps of: assigning the first disk apparatus to using the first copy mode and the second disk apparatus to using the second copy mode; sending, by the host computer, a write request including the update log data, and a write destination to store the update log data, to the first storage system; receiving, by the first storage system, the write request from the first computer; storing, by the first storage system, the update history information, based on the write destination to either the first disk apparatus in the first copy mode or the second disk apparatus in the second copy mode; holding the update history information in either the cache memory for the first copy mode or the side file memory for the second copy mode; transferring, by the first storage system, the update history information to the second storage system via the remote copy line in the first copy mode or the second copy mode; sending completion notification of the write request to the host computer either after confirmation of receiving in the second storage system for the first copy mode or without confirmation of receiving in the second storage system for the second copy mode; monitoring, by the first storage system, use rate of the remote copy line to transfer the update log data from the first storage system to the second storage system; if a monitored use rate is a first predetermined value, sending, by the first storage system, a notification for changing copy mode to the host computer; changing, by the host computer, a write destination between either the first disk apparatus for the first copy mode or the second disk apparatus for the second copy mode if the notification is received from the first storage system; sending, by the first host computer, to the first storage system, a record for change history of the write destination to the first storage system; and, storing, by the first storage system, a record for change history of the write destination to either the first disk apparatus or the second disk apparatus.