Remote copy for a storage controller in a heterogeneous environment

• US 7,213,114 B2
• Filed: 08/12/2004
• Issued: 05/01/2007
• Est. Priority Date: 05/10/2001
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Okami, Yoshinori, Nakano, Toshio, Kishiro, Shigeru, Higaki, Seiichi, Abei, Hiroshi, Nakamura, Katsunori, Ogata, Mikito, Koide, Takeshi, Nagasawa, Teruo
• Primary Examiner(s): Bragdon; Reginald
• Assistant Examiner(s): Namazi; Mehdi
• Application Number:
  US10/917,800
• Publication Number:
  US 20050120093A1
• Time in Patent Office: 992 Days
• Field of Search: None
• US Class Current: 711/162
• CPC Class Codes: G06F 11/2058 using more than 2 mirrored copies
• CPC Class Codes: G06F 11/2082 Data synchronisation

Abstract

Two data centers located in the vicinity are connected using a synchronous transfer copy function, and one of the data centers is coupled with a third data center disposed at a remote location by an asynchronous remote copying function. The order whereat a storage sub-system located in the vicinity has received data from a host is consistently guaranteed, and the third data center holds the data. Further, each storage sub-system includes a function whereby, during normal operation, data can be exchanged and the data update state can be obtained by the storage sub-systems located in the two data centers that do not directly engage in data transmission.

Claims

1. A storage system comprising:

a first storage component configured for connection to a host and operative to receive write requests from the host;

a second storage component configured for synchronous data transfer of data from the first storage component; and

a third storage component configured for asynchronous data transfer of data from the first storage component,

the first storage component comprising a first disk controller,

the second storage component comprising a path replacement controller,

the storage system further comprising a first communication path between the path replacement controller and the first disk controller,

the path replacement controller operative to receive a first write request from the host and to communicate data associated with the first write request to the first storage component.

2. The storage system of claim 1 wherein the second storage component is operative to service the first write request by storing the data associated with the first write request to a data volume in the second storage component.

3. A storage system comprising:

a first storage component comprising a disk controller and configured for connection to a host and operative to receive write requests from the host;

a second storage component configured for synchronous data transfer of data from the first storage component;

a third storage component configured for asynchronous data transfer of data from the first storage component;

a fourth storage component comprising a path replacement controller; and

a communication path between the path replacement controller and the first disk controller,

the path replacement controller operative to receive a first write request from the host and to communicate the first write request to the first storage component.

4. A remote copy method in a storage system comprising a first storage sub-system configured for communication with a host system and operative to exchange data with the host, a second storage sub-system in data communication with the first storage sub-system, and a third storage sub-system in data communication with the first storage sub-system, the method comprising:

operating in a first configuration, comprising steps of;

receiving, in the first storage sub-system, first I/O requests from the host including first read requests and first write requests;

storing data associated with the first write requests on a data volume in the first storage sub-system;

synchronously transferring data stored in the first storage system to the second storage system; and

asynchronously transferring data stored in the first storage system to the third storage system; and

operating in a second configuration, comprising steps of;

receiving, in the second storage sub-system, second I/O requests from the first host including second read requests and second write requests;

communicating the second I/O requests to the first storage sub-system;

storing data associated with the second write requests on the data volume in the first storage sub-system;

synchronously transferring data stored in the first storage system to the second storage system; and

asynchronously transferring data stored in the first storage system to the third storage system.

5. A remote copy method in a storage system comprising a first storage sub-system configured for communication with a host system and operative to exchange data with the host, a second storage sub-system in data communication with the first storage sub-system, and a third storage sub-system in data communication with the first storage sub-system, the method comprising:

operating in a first configuration, comprising steps of;

receiving, in the first storage sub-system, first I/O requests from the host including first read requests and first write requests;

storing data associated with the first write requests on a data volume in the first storage sub-system;

synchronously transferring data stored in the first storage system to the second storage system; and

asynchronously transferring data stored in the first storage system to the third storage system; and

operating in a second configuration, comprising steps of;

receiving, in the second storage sub-system, second I/O requests from the first host including second read requests and second write requests;

storing data associated with the second write requests on a data volume in the second storage sub-system;

synchronously transferring data associated with the second write requests to the first storage system; and

asynchronously transferring data stored in the first storage system to the third storage system.

6. A remote copy method in a storage system comprising a first storage sub-system configured for communication with a host system and operative to exchange data with the host, a second storage sub-system in data communication with the first storage sub-system, a third storage sub-system in data communication with the first storage sub-system, and a fourth storage sub-system in communication with the first storage sub-system, the method comprising:

receiving, in the first storage sub-system, a first write request from the host;

storing first data associated with the first write request to data volumes in the first storage sub-system;

synchronously transferring the first data to the second storage sub-system at a time subsequent to receiving the first write request;

asynchronously transferring the first data to the third storage sub-system at a time subsequent to receiving the first write request;

receiving, in the fourth storage sub-system, a second write request from the host;

communicating the second write request to the first storage sub-system;

storing second data associated with the second write request to data volumes in the first storage sub-system;

synchronously transferring the second data to the second storage sub-system at a time subsequent to receiving the second write request; and

asynchronously transferring the second data to the third storage sub-system at a time subsequent to receiving the second write request.

7. The method of claim 6 further comprising:

receiving, in the fourth storage sub-system, a third write request from the host, wherein the host is no longer able to communicate with the first storage sub-system;

storing third data associated with the third write request to data volumes in the fourth storage sub-system;

synchronously transferring the third data to the second storage sub-system from the fourth storage sub-system at a time subsequent to receiving the third write request; and

asynchronously transferring the third data to the third storage sub-system from the fourth storage sub-system at a time subsequent to receiving the third write request.