Remote copy system

• US 8,700,725 B2
• Filed: 12/23/2011
• Issued: 04/15/2014
• Est. Priority Date: 06/23/2003
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Yamagami, Kenji
• Primary Examiner(s): Nguyen, Tammy
• Application Number:
  US13/336,408
• Publication Number:
  US 20120096308A1
• Time in Patent Office: 844 Days
• Field of Search: 709/212, 709/224, 709/246, 711/162, 711/161, 711/165, 707/616
• US Class Current: 709/212
• CPC Class Codes: G06F 11/2074 Asynchronous techniques
• CPC Class Codes: G06F 11/2076 Synchronous techniques
• CPC Class Codes: G06F 16/10 File systems; File servers
• CPC Class Codes: G06F 2201/855 Details of asynchronous mirroring using a journal to transfer not-yet-mirrored changes
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: H04L 67/56 Provisioning of proxy services store-and-forward switching systems in data switching networks H04L12/54
• CPC Class Codes: H04L 67/59 Providing operational support to end devices by off-loading in the network or by emulation, e.g. when they are unavailable
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

A remote copy system includes a first storage system including a first storage controller arid a first data volume. The first storage controller is configured to control data access requests to the first data volume. The first storage system is configured to store write data in the first data volume upon receiving a write request from a first host associated with the first storage system and generate a journal including control data and journal data A second storage system includes a journal volume and configured to receive and store the journal generated by the first storage system in the journal volume. A third storage system includes a second data volume and configured to receive the journal from the second storage system and store the journal data of the journal to the second storage system according to information provided in the control data.

Claims

1. A remote copy system, comprising:

a first storage system including a first storage controller and a first data volume, the first storage controller being configured to receive a write request from a first host and to store write data associated with the write request to the first data volume;

a second storage system coupled to the first storage system, including a second storage controller and a first storage area, the second storage controller receiving first data containing the write data to copy the stored data in the first data volume to the first storage area; and

a third storage system coupled to the second storage system, including a third storage controller, a second storage area and a second data volume,

wherein the write request from the first host to the first storage system completes after the second storage system completes a process of receiving the first data, and

wherein the third storage controller is configured to complete a process of storing the first data received from the second storage system to the second storage area at a timing that is independent of a completion of processing of the write request from the first host.

2. The remote copy system of claim 1, wherein the first storage area temporarily stores the first data received from the first data volume.

3. The remote copy system of claim 1, wherein the first storage area is a cache memory.

4. The remote copy system of claim 1, wherein the second storage system further comprises a third data volume which stores the first data when the first storage system is idle.

5. The remote copy system of claim 1, further comprising:

a second host coupled to the second storage system, wherein the second storage system is configured to function as a primary storage system if the first storage system experiences a failure.

6. The remote copy system of claim 1, further comprising a third host coupled to the third storage system, wherein the third storage system is configured to replace the first storage system as a primary storage system if the first storage, system experiences a failure.

7. The remote copy system of claim 1, wherein the first data further includes a time when the write data are stored in the first data volume based on the write request from the first host.

8. The remote copy system of claim 1, wherein the first data is received at the second data volume after the write data are copied to the second storage system to secure the write data when the first storage system experiences a failure.

9. A remote copy method for a remote copy system, comprising:

receiving a write request from a first host;

storing write data associated with the write request to the first data volume in a first storage system;

receiving first data containing the write data to copy the stored data in the first data volume to a first storage area in a second storage system;

completing the write request from the first host to the first storage system after the second storage system completes a process of receiving the first data; and

completing a process of storing the first data received from the second storage system to a second storage area in a third storage system at a timing that is independent of a completion of processing of the write request from the first host.

10. The remote copy method of claim 9, wherein the first storage area temporarily stores the first data received from the first data volume.

11. The remote copy method of claim 9, wherein the first storage area is a cache memory.

12. The remote copy method of claim 9, wherein the second storage system further comprises a third data volume which stores the first data when the first storage system is idle.

13. The remote copy method of claim 9, wherein the second storage system is coupled to a second host and configured to function as a primary storage system if the first storage system experiences a failure.

14. The remote copy method of claim 9, wherein the third storage system is coupled to the a third host and configured to replace the first storage system as a primary storage system if the first storage system experiences a failure.

15. The remote copy method of claim 9, wherein the first data further includes a time when the write data are stored in the first data volume based on the write request from the first host.

16. The remote copy method of claim 9, wherein the first data is received at the second data volume after the write data are copied to the second storage system to secure the write data when the first storage system experiences a failure.