Patent ID: 7200725
Filing Date: 2007-04-03
Classification: G06F

Abstract:
1. An information processing system comprising: a first site that is connected to a first computer and has a first storage system and a second storage system; and a second site having a third storage system connected to a second computer and to the first storage system, and a fourth storage system connected to the second computer and to the second storage system; wherein the third storage system has a first memory area for storing data transferred from the first storage system, and a second memory area and third memory area for storing a copy of the data stored in the first memory area of the third storage system; the fourth storage system has a first memory area for storing data transferred from the first storage system, and a second memory area and third memory area for storing a copy of the data stored in the first memory area of the fourth storage system; the first storage system and the second storage system each receive data with an attached writing time from the first computer; the first storage system transfers to the third storage system the data received from the first computer and a copy of the writing time; the second storage system transfers to the fourth storage system the data received from the first computer and a copy of the writing time; the third storage system writes to the first memory area in the third storage system the data received from the first storage system in the time sequence in which the data were attached, and writes to the second memory area in the third storage system a copy of the data written in the first memory area in the third storage system in the time sequence in which the data were attached; the fourth storage system writes to the first memory area in the fourth storage system the data received from the second storage system in the time sequence in which the data were attached, and writes to the second memory area in the fourth storage system a copy of the data written in the first memory area in the fourth storage system in the time sequence in which the data were attached; when copying is completed to the second memory area in the third storage system of the data with an attached writing time that is prior to a first prescribed time specified by the first computer, the third storage system suspends writing to the second memory area in the third storage system of a copy of the data written in the first memory area in the third storage system; the third storage system then initiates writing of a copy of the data written in the first memory area in the third storage system to the third memory area in the third storage system; when copying is completed to the second memory area in the fourth storage system of the data with an attached writing time that is prior to a first prescribed time specified by the first computer, the fourth storage system suspends writing to the second memory area in the fourth storage system of a copy of the data written in the first memory area in the fourth storage system; and the fourth storage system then initiates writing of a copy of the data written in the first memory area in the fourth storage system to the third memory area in the fourth storage system.