Storage management task distribution method and system on storage virtualizer

• US 8,347,043 B2
• Filed: 03/25/2009
• Issued: 01/01/2013
• Est. Priority Date: 03/25/2009
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Murase, Atsushi
• Primary Examiner(s): Rutz, Jared
• Assistant Examiner(s): Bertram, Ryan
• Application Number:
  US12/411,290
• Publication Number:
  US 20100250845A1
• Time in Patent Office: 1,378 Days
• Field of Search: 711/111, 711/148, 711/154, 709/217
• US Class Current: 711/148
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/0631 by allocating resources to storage systems
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 9/5088 involving task migration
• 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]

Abstract

Systems and methods for dissolving the bottleneck issue of management task requested from management client to the storage virtualizer which consolidates externally attached storage arrays while providing a single management point of the entire system to the management client. Specifically, by utilizing the storage virtualizer to distribute received management tasks to respective external attached arrays, it can off load tasks, thus reducing the workload on the storage virtualizer itself. Because of the task distribution, the storage virtualizer consequently does not need to copy and hold detailed information of each storage volume in the respective attached storage arrays, thereby avoiding any inconsistent information between the arrays and the virtualizer when the configuration change has been done on the external array.

Claims

1. A computerized storage system comprising:

a plurality of storage arrays, each storage array comprising a controller;

a storage virtualizer, to which the plurality of storage arrays are externally attached so that a plurality of storage volumes in the plurality of storage arrays are virtually represented to a host as if the plurality of volumes exist on the storage virtualizer, the storage virtualizer, comprising a storage virtualizer management module;

a management client sending a management command to the storage virtualizer;

wherein the storage virtualizer management module comprises instructions for;

receiving a command from the management client;

selecting a storage array from the plurality of storage arrays; and

delegating the received management command to the selected storage array for processing;

wherein the selected storage array sends a result of the delegated received command directly to the management client;

wherein the storage virtualizer management module further comprises instructions that execute a process for sending a notice to the management client that the command sent from the management client has been asynchronously started; and

wherein the notice indicates the command has been distributed and performed; and

wherein the notice indicates that a plurality of results will be sent back.

2. The computerized storage system of claim 1, wherein the storage virtualizer management module further comprises instructions that execute a process for determining if a command sent from the management client should be delegated or executed by the storage virtualizer.

3. The computerized storage system of claim 2, wherein if the storage virtualizer determines that the command sent from the management client should be delegated, the storage virtualizer sends a request to the plurality of storage arrays that a result of the command be sent directly to the management client instead of the storage virtualizer.

4. The computerized storage system of claim 2, wherein if the storage virtualizer determines that the command sent from the management client should be delegated, the storage virtualizer subscribes indication listener information to each of the plurality of storage arrays and forwards the command to the each of the plurality of storage arrays, and wherein the each of the plurality of storage arrays sends the result of the command to indication listener specified in the indication listener information.

5. The computerized storage system of claim 4, wherein if it is determined that the command sent from the management client is delegated, and when all the results of the command performed in the each of the plurality of storage arrays are sent to the indication listener, the indication listener sends acknowledgement to the storage virtualizer, and wherein the storage virtualizer unsubscribes the indication listener information from the storage arrays.

6. The computerized storage system of claim 2, wherein the storage virtualizer responds to the management client either with the notice or the result of the received command based on the determination.

7. The computerized storage system of claim 2, wherein the storage virtualizer further comprises a unified storage volume table holding attributes for the storage volumes in the plurality of storage arrays and for storage volumes in the storage virtualizer.

8. The computerized storage system of claim 7, wherein the unified storage table comprises ID information of the storage volumes in the plurality of storage arrays and of the storage volumes in the storage virtualizer.

9. The computerized storage system of claim 8, wherein the unified storage table further comprises size of the storage volumes in the plurality of storage arrays.

10. The computerized storage system of claim 2, wherein the determination is based on a comparison between a threshold and a total number of available storage volumes in the storage virtualizer and the plurality of storage arrays;

and wherein if the total number of available storage volumes exceeds the threshold, then the storage virtualizer management module delegates the command sent from the management client to all storage arrays and wherein if the total number of available storage volumes is smaller than the threshold, then the storage virtualizer executes the command sent from the management client for the storage volumes.

11. The computerized storage system of claim 2, wherein the determination is based on a comparison between a threshold and a total number of available storage volumes in a storage array of the plurality of storage arrays, and wherein if the total number of available storage volumes in the storage array of the plurality of storage arrays exceeds the threshold, then the storage virtualizer management module delegates the command sent from the management client to the storage array, and if the total number of available storage volumes in the storage array of the plurality of storage arrays is smaller than the threshold, then the storage virtualizer executes the command sent from the management client for the storage volumes in the storage array.

12. The computerized storage system of claim 1 further comprising an external array table comprising access information of the storage arrays, wherein the selecting a storage array is done by selecting a storage array from the external array table.

13. The computerized storage system of claim 8, wherein each of the plurality of storage arrays further comprises a storage volume table that holds identification and attribute values of the storage volumes in the respective storage array.

14. The computerized system of claim 2, wherein the storage virtualizer further comprises a controller, a CPU, and a program module handling execution of management commands.

15. The computerized system of claim 2, wherein each of the plurality of the storage arrays further comprises a controller, a CPU, and a program module handling execution of commands.

16. The computerized system of claim 11, wherein the selected storage array utilizes the controller, the CPU, and the program module to execute the management command delegated from the storage virtualizer so as to distribute management workload related to the storage volumes in the storage array.

17. The computerized system of claim 1, wherein the storage management client module of the management client handles receiving the plurality of results from either the plurality of storage arrays or from the storage virtualizer.

18. The computerized storage system of claim 17, wherein the result is concatenated such that the management client can keep a full list of management command results.