Hitachi, Ltd.

Hidehiko Kimura

Masaki Aizawa

Fumio Yamaguchi

Proposed are a copy system and a copy method capable of performing initial copy in a short amount of time and with high reliability. On a primary side, the area in the first volume to which data was written from the host is managed, a second bitmap is created reflecting the contents of the first bitmap, and the second bitmap is sent to the secondary side on the primary side. On a secondary side, a third bitmap to which the second bitmap sent from the primary-side is merged is created, on the primary side, only the valid data containing data written by the host in the first volume is copies to the second volume based on the second bitmap, and, on the secondary-side, the differential between the first and second volumes during the initial copy is managed based on the third bitmap.

Growing community of inventors

Odawara, Japan

Hidehiko Kimura