Storage system and storage control device

• US 20050060506A1
• Filed: 02/02/2004
• Published: 03/17/2005
• Est. Priority Date: 09/16/2003
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Okami, Yoshinori, Nakano, Toshio, Shimada, Akinobu, Higaki, Seiichi
• Granted Patent: US 7,111,138 B2
• Time in Patent Office: Days
• US Class Current: 711/162
• CPC Class Codes: G06F 11/1456 Hardware arrangements for backup
• CPC Class Codes: G06F 11/1458 Management of the backup or restore process
• CPC Class Codes: G06F 11/1466 to make the backup process non-disruptive
• CPC Class Codes: G06F 2201/80 Database-specific techniques
• CPC Class Codes: G06F 3/0607 by facilitating the process of upgrading existing storage systems, e.g. for improving compatibility between host and storage device
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/0659 Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• CPC Class Codes: G06F 3/0683 Plurality of storage devices
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30
• CPC Class Codes: H04L 67/1029 using data related to the state of servers by a load balancer
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

A first storage control device is provided with a virtual LU for showing a logical volume possessed by a second storage control device as if it were its own volume. When data processing requested from a host device is, for example, a specific processing of large load (such as direct backup, logical volume copy, and so on), whether or not the requested processing can be executed by the second storage control device is judged. When it is executable, a command is transmitted to the second storage control device to make it take over the processing.

Claims

1. A storage system comprising a first storage control device and a second storage control device connected so as to be capable of communicating with each other and executing data processing according to a request from a host device,

wherein the first storage control device comprises:

first control means for judging whether or not the second storage control device can execute a predetermined data processing function relating to a first request received from the host device and, when it is judged that the second control device can execute, generating a second request corresponding to the first request and transmitting it to the second storage control device,

wherein the second storage control device comprises;

second control means for executing the predetermined data processing function based on the second request received from the first storage control device such that the second storage control device takes over said predetermined data processing function relating to a first request from the first storage control device, and

wherein said predetermined data processing function includes direct backup, internal copying process between a pair of volumes, mirroring, or remote copying.

2. A storage system according to claim 1, wherein the first storage control device provides a second storage area controlled by the second storage control device to the host device virtually as the first storage area under control of its own, and the first request requests the data processing relating to the first storage area.

3. A storage system according to claim 2, wherein the first storage control device is to retain storage areas correspondence information indicating correspondence between the first storage area and the second storage area and to provide the first storage area virtually to the host device based on the storage areas correspondence information, so that the first storage means can execute data processing directed to the first storage area by the first request based on the storage areas correspondence information.

4. A storage system according to claim 1, wherein the second request is configured to have the similar data structure to the first request.

5. A storage system according to claim 1, wherein the first control means confirms whether or not the second storage control device can execute the predetermined data processing function relating to the first request before transmitting the second request to the second storage control device.

6. A storage system according to claim 1, wherein the first storage control device retains function management information showing data processing functions executable by the second storage control device, and

the first control means judges whether or not the second storage control device can execute the predetermined data processing function relating to the first request based on the function management information.

7. A storage system according to claim 6, wherein the function management information is generated manually or automatically at the time of definition of the storage system configuration.

8. A storage system according to claim 2, further comprising a backup device connected to both of the first storage control device and the second storage control device so as to be capable of communicating with each other,

wherein, in the case where data processing function relating to the first request is the direct backup processing function for transmitting and storing information stored in the first storage area to the backup device, the first control means judges whether or not the second storage control device can execute the direct backup processing function, and when it is judged that the second storage control device can execute the direct backup processing function, generates the second request by converting the address of the first storage area contained in the first request into the address in the second storage area and transmits it to the second storage control device, and

wherein the second control means transfers and stores information stored in the second storage area to the backup device based on the second request.

9. A storage system according to claim 2, wherein the first storage control device further provides a first secondary storage area paired with the first storage area virtually, and the second storage control device further includes a second secondary storage area paired with the second storage area,

wherein, in the case where the predetermined data processing function relating to the first request is the internal copying processing function for copying information stored in the first storage area into the first secondary storage area, the first control means judges whether or not the second storage control device can execute the internal copying processing function,

wherein, when it is judged that the second storage control device can execute the internal copying processing function, the first control means generates and transmits the second request to the second storage control device by converting the address of the first storage area contained in the first request to the address of the second storage area, and

wherein the second control means copies information stored in the second storage area into the second secondary storage area based on the second request.

10. A storage system according to claim 2, comprising a subsite which pairs with a main site including the first storage control device and the second storage control device, and being connected to the main site so as to be capable of communicating with each other, wherein the subsite comprises a remanent first storage control device and a remanent second storage control device, and the remanent first storage control device virtually provides a remanent second storage area controlled by the remanent second storage control device as a remanent first storage area which the remanent first storage control device controls,

wherein when the predetermined data processing function relating to the first request is the mirroring processing function for copying information stored in the first storage area to the remanent first storage area of the subsite, the first control means of the main site judges whether or not both of the second storage control device and the remanent second storage control device can execute the mirroring processing function and, when it is judged that the respective second storage control device can execute the mirroring processing function, generates the second request corresponding to the first request, and transmits it to the second storage control device, and

wherein the second control means executes the external copying mirroring processing function by copying information stored in the second storage area to the remanent second storage area based on the second request.

11. A storage system according to claim 10, wherein the remanent first storage control device retains remanent function management information indicating data processing functions that the remanent second storage control device can execute, and

wherein the first control means judges whether or not the remanent second storage control device can execute the mirroring processing function by sending inquiries to the remanent first storage control device before transmitting the second request to the second storage control device.

12. A storage system according to claim 10, wherein the first storage control device retains storage areas correspondence information indicating correspondence between the first storage area and the second storage area,

wherein the remanent first storage control device retains remanent storage areas correspondence information indicating correspondence between the remanent first storage area and the remanent second storage area, and

wherein the first control means transmits respective storage areas correspondence information when transmitting the second request to the second storage control device.

13. A storage system according to claim 10, wherein the first storage control device comprises a renewed positional information retaining means for retaining information relating to the first storage area renewed by the host device during the mirroring processing, and

wherein the first control means generates the second request, reads renewed information from the second storage control device, and transmits the read information in order to store information renewed in the first storage area to the remanent first storage area based on the renewed positional information retaining means when the mirroring processing is completed.

14. A control method for a storage system comprising a first storage control device and a second storage control device connected to communicate with each other thereby executing data processing according to requests from a host device, wherein the first storage control device performing the steps of:

receiving a first request from the host device,

judging whether or not the second storage control device can execute a predetermined data processing function relating to the received first request,

generating a second request corresponding to the first request when it is judged that the second storage control device can execute, and transmitting the generated second request to the second storage control device, and

wherein the second storage control device executing the steps of;

receiving the second request from the first storage control device, and

executing the predetermined data processing function based on the received second request such that the second storage control device takes over said predetermined data processing function relating to a first request from the first storage control device, and

wherein said predetermined data processing function includes direct backup, internal copying process between a pair of volumes, mirroring, or remote copying.

15. A storage control device connected to a second storage control device and a host device to communicate with each other for executing data processing according to a request from the host device, comprising:

receiving means for receiving a first request from the host device,

judging means for judging whether the second storage control device can execute a predetermined data processing function relating to the received first request,

requesting means for generating a second request corresponding to the first request when it is judged that the second storage control device can execute the predetermined data processing function, and

transmitting means for transmitting the generated second request to the second storage control device such that the second storage control device takes over said predetermined data processing function relating to a first request from the first storage control device, and

wherein said predetermined data processing function includes direct backup, internal copying process between a pair of volumes, mirroring, or remote copying.

16. A program stored in a computer readable medium connected to a second storage control device and a host device to communicate with each other for controlling a first storage control device thereby executing data processing according to a request from the host device, comprising:

a module for judging whether or not the second storage control device can execute a predetermined data processing function relating to the first request received from the host device,

a module for generating a second request corresponding to the first request when it is judged that the second storage control device can execute, and

a module for transmitting the generated second request to the second storage control device from the first storage control device such that the second storage control device takes over said predetermined data processing function relating to a first request from the first storage control device,

wherein said predetermined data processing function includes direct backup internal copying process between a pair of volumes, mirroring, or remote copying.