Patent ID: 7287132
Filing Date: 2007-10-23
Classification: G06F

Abstract:
1. A method for copying data from a primary system having a first storage apparatus having a first logical volume to a secondary system having a second storage apparatus having a second logical volume and a third system having a third storage apparatus having a third logical volume, comprising steps of: by the first storage apparatus, transmitting data of the first logical volume, from the first storage apparatus to the third storage apparatus, to store the data in the third logical volume, by a synchronous remote copy procedure; by the first storage apparatus, transmitting data of the first logical volume, from the first storage apparatus to the second storage apparatus, to store the data in the second logical volume, by an asynchronous remote copy procedure; by the third storage apparatus, recording location information of data, received from the first storage apparatus by the synchronous remote copy procedure, by using a plurality of bitmaps having plural bits corresponding to locations in the third logical volume; by an information processing apparatus coupled to the first storage apparatus, issuing a first instruction to cause a state change to the first storage apparatus; by the first storage apparatus, for transmitting data of the first logical volume from the first storage apparatus to the second storage apparatus by the asynchronous remote copy procedure, managing transmission of data from the first storage apparatus to the second storage apparatus, wherein while certain data are transmitted from the first storage apparatus to the second storage apparatus, another data received at the first storage apparatus are held in the first storage apparatus, and after completion of transmission of the certain data from the first storage apparatus to the second storage apparatus, the state change occurs according to the first instruction to cause transmission of the another data from the first storage apparatus to the second storage apparatus; and by the third storage apparatus, in response to second instruction received from the primary system, clearing one or the plurality of bitmaps at a timing related to the state change.