REMOTE COPY METHOD AND REMOTE COPY SYSTEM

• US 20100199038A1
• Filed: 09/30/2009
• Published: 08/05/2010
• Est. Priority Date: 06/27/2003
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Hirakawa, Yusuke, Ito, Ryusuke, Sato, Takao, Arakawa, Hiroshi, Asaka, Yoshihiro, Takeda, Takahiko, Kaga, Takashi
• Granted Patent: US 8,234,471 B2
• Time in Patent Office: Days
• US Class Current: 711/113
• CPC Class Codes: G06F 11/2066 Optimisation of the communication load
• CPC Class Codes: G06F 11/2074 Asynchronous techniques
• CPC Class Codes: G06F 2201/855 Details of asynchronous mirroring using a journal to transfer not-yet-mirrored changes
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

In a configuration in which it is necessary to transfer data from a first storage system to a third storage system through a storage system between the storage systems, there is a problem that it is inevitable to give an excess logical volume to a second storage system between the storage systems. A remote copy system includes first storage system that sends and receives data to and from an information processing apparatus, a second storage system, and a third storage system. The second storage system virtually has a second storage area in which the data should be written and has a third storage area in which the data written in the second storage area and update information concerning the data are written. Data sent from the first storage system is not written in the second storage area but is written in the third storage area as data and update information. The data and the update information written in the third storage area are read out from the third storage system.

Claims

1. A remote copy system comprising:

a first storage system having a first logical volume provided with a plurality of disk drives in the first storage system;

a second storage system having a second logical volume, which is a virtual volume; and

a third storage system having a third logical volume provided with a plurality of disk drives in the third storage system, the third logical volume storing copied data of data stored in the first logical volume,

wherein, if the first storage system receives a write data sent from a host computer to the first logical volume, the first storage system sends the write data to the virtual volume in the second storage system according to a synchronous remote copy procedure,

wherein the second storage system receives the write data sent from the first storage system to the virtual volume, stores the write data in a cache memory of the second storage system, and sends the write data to the third logical volume in the third storage system according to an asynchronous remote copy procedure, wherein the second storage system does not store the write data in the virtual volume, and

wherein the third storage system receives the write data sent from the second storage system to the third logical volume, and stores the write data in the third logical volume.

2. The remote copy system according to claim 1, wherein the first storage system stores the write data received from the host computer in the first logical volume.

3. The remote copy system according to claim 1, wherein the virtual volume is not provided with a plurality of disk drives in the second storage system.

4. The remote copy system according to claim 1, wherein the virtual volume configures a synchronous remote copy pair with the first logical volume and an asynchronous remote copy pair with the third logical volume.

5. The remote copy system according to claim 1, wherein the virtual volume functions as a secondary volume to the first logical volume and as a primary volume to the third logical volume.

6. The remote copy system according to claim 1,

wherein the remote copy system further comprises another host computer coupled to the third storage system, and

wherein, if a failure occurs in the first storage system, the third storage system takes over for the first storage system with the copied data of the first logical volume being stored in the third logical volume.

7. The remote copy system according to claim 1,

wherein the second storage system manages a volume identifier of the virtual volume as if the second logical volume, corresponding to the virtual volume, is provided with a plurality of disk drives in the second storage system.

8. A remote copy system comprising:

a first storage system managing a first volume identifier of a first logical volume provided with a plurality of disk drives in the first storage system;

a second storage system managing a second volume identifier as if a second logical volume exists in the second storage system to configure a remote copy target volume to the first storage system; and

a third storage system managing a third volume identifier of a third logical volume provided with a plurality of disk drives in the third storage system, the third logical volume storing copied data of data stored in the first logical volume,

wherein, if the first storage system receives a write data sent from a host computer to the first volume in the first storage system, the first storage system sends the write data to the second volume in the second storage system according to a first remote copy procedure,

wherein the second storage system receives the write data sent from the first storage system to the second volume, stores the write data in a cache memory of the second storage system, and sends the write data to the third logical volume in the third storage system according to a second remote copy procedure, and

wherein the third storage system receives the write data sent from the second storage system to the third logical volume, and stores the write data in the third logical volume.

9. The remote copy system according to claim 8, wherein the first storage system stores the write data received from the host computer in the first logical volume.

10. The remote copy system according to claim 8, wherein the second logical volume is not allocated to a plurality of disk drives in the second storage system.

11. The remote copy system according to claim 8, wherein the first remote copy procedure is a synchronous remote copy procedure, and the second remote copy procedure is an asynchronous remote copy procedure.

12. The remote copy system according to claim 8, wherein the second logical volume configures a synchronous remote copy pair with the first logical volume and an asynchronous remote copy pair with the third logical volume.

13. The remote copy system according to claim 8, wherein the second logical volume functions as a secondary volume to the first logical volume and as a primary volume to the third logical volume.

14. The remote copy system according to claim 8,

wherein the remote copy system further comprises another host computer coupled to the third storage system, and

wherein, if a failure occurs in the first storage system, the third storage system takes over for the first storage system with the copied data of the first logical volume being stored in the third logical volume.

15. A remote copy system comprising:

a first storage system having a first logical volume provided with a plurality of disk drives in the first storage system;

a second storage system having a virtual volume, and the virtual volume is used to configure a first remote copy pair with the first logical volume; and

a third storage system having a second logical volume provided with a plurality of disk drives in the third storage system, the second logical volume storing copied data of the first logical volume, and the second logical volume is used to configure a second remote copy pair with the virtual volume,

wherein, if the first storage system receives a write data sent from a host computer to the first logical volume, the first storage system sends the write data to the virtual volume in the second storage system according to a first remote copy procedure,

wherein the second storage system receives the write data sent from the first storage system to the virtual volume, stores the write data in a cache memory of the second storage system, and sends the write data to the second logical volume in the third storage system according to a second remote copy procedure, and

wherein the third storage system receives the write data sent from the second storage system to the second logical volume, and stores the write data in the second logical volume.

16. The remote copy system according to claim 15, wherein the first storage system stores the write data received from the host computer in the first logical volume.

17. The remote copy system according to claim 15, wherein the first remote copy procedure is a synchronous remote copy procedure and the second remote copy procedure is an asynchronous remote copy procedure.

18. The remote copy system according to claim 15, wherein the virtual volume is not provided with a plurality of disk drives in the second storage system.