Storage system, data processing method and storage apparatus

• US 20070180168A1
• Filed: 03/16/2006
• Published: 08/02/2007
• Est. Priority Date: 02/01/2006
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Hitachi, Ltd.
• Inventors: Kumasawa, Hiroyuki, Chikusa, Takashi, Yamaura, Satoru, Yukawa, Masashi, Nakama, Hironori
• Granted Patent: US 7,558,916 B2
• Time in Patent Office: Days
• US Class Current: 710/74
• CPC Class Codes: G06F 11/1435 using file system or storage system metadata
• CPC Class Codes: G06F 11/1662 the resynchronized component or unit being a persistent storage device re-synchronization of failed mirror storage G06F11/2082; rebuild or reconstruction of parity RAID storage G06F11/1008
• CPC Class Codes: G06F 11/2092 Techniques of failing over between control units
• CPC Class Codes: G06F 11/2094 Redundant storage or storage space G06F11/2056 takes precedence
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data
• CPC Class Codes: G06F 3/0617 in relation to availability
• CPC Class Codes: G06F 3/0626 Reducing size or complexity of storage systems
• CPC Class Codes: G06F 3/0635 by changing the path, e.g. traffic rerouting, path reconfiguration
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/0664 at device level, e.g. emulation of a storage device or system
• 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 67/14 Session management for real-time applications in data packet communications networks H04L65/1066

Abstract

Proposed are a storage system, data processing method and storage apparatus capable of performing stable data I/O processing. Each of the storage apparatuses configured in the storage group stores group configuration information containing priority information given to each storage apparatus, and the storage apparatus with the highest priority becomes a master and performs virtualization processing and data I/O processing, and another storage apparatus belonging to this storage group performs internal processing of the storage group.

Claims

1. A storage system in which a plurality of storage apparatuses are connected to a network,

wherein said storage apparatus retains an identifier for identifying a storage group to which a preconfigured own storage apparatus belongs;

and

retains configuration information of each of said storage apparatuses, priority information representing the priority of said storage apparatus in said storage group and management information of the overall storage group which are common among all of said storage apparatuses configured in the same storage group; and

wherein one or more first storage apparatuses of a master for performing virtualization processing of said storage apparatus in said storage group units and data I/O processing from a host system, and one or more second storage apparatuses for performing data migration involving internal processing are configured.

2. The storage system according to claim 1, wherein said storage apparatus other than said first storage apparatus in said storage group does not reply that it is an operable storage apparatus to a discovery request from said host system.

3. The storage system according to claim 1, wherein a volume in said storage apparatus virtualized with said first storage apparatus is disposed redundantly in said plurality of storage apparatuses configuring said same storage group.

4. The storage system according to claim 1,

wherein said second storage apparatus performs said data migration involving internal processing according to instructions from said first storage apparatus;

and

wherein said first storage apparatus transmits prescribed metadata to said second storage apparatus upon designating said internal processing to said second storage apparatus.

5. The storage system according to claim 1, wherein, when a failure occurs in said first storage apparatus or said second storage apparatus in said same storage group, said storage apparatus with the next highest priority after said first storage apparatus or said second storage apparatus subject to a failure takes over the functions of said first storage apparatus or said second storage apparatus subject to said failure based on said priority information of each of said storage apparatuses.

6. The storage system according to claim 1, wherein, when said storage apparatus is configured to belong to a plurality of said storage groups, said storage apparatus retains, per said storage group, configuration information and priority information of each of said storage apparatuses configured in said storage group and management information of the overall storage group.

7. The storage system according to claim 6, wherein configuration information and priority information of each of said storage apparatuses configured in said storage group and management information of the overall storage group are configured to have different characteristics in each of said storage groups among said storage groups.

8. The storage system according to claim 2, wherein said storage apparatus belongs to the same storage group as the own storage apparatus, and does not reply that it is an operable storage apparatus to a discovery request from said storage apparatus other than said storage apparatus with said priority in said storage group that is equal to or higher than the own storage apparatus.

9. The storage system according to claim 3, wherein, when the access from said host system is a data I/O request of files in said storage apparatus virtualized in said storage group units, the number of said storage apparatuses retaining metadata of said virtual volume is less than the number of said storage apparatuses configuring said virtual volume.

10. The storage system according to claim 4, wherein said second storage apparatus makes an inquiry to said first storage apparatus if it does not receive said metadata to be transmitted from said first storage apparatus for over a certain period of time.

12. The data processing method according to claim 10, wherein, at said second step, a second storage apparatus given a priority that is next highest after said first storage apparatus as the master as said priority in said storage group performs said internal processing.

13. The data processing method according to claim 12, further comprising a third step wherein, when a failure occurs in said first storage apparatus or said second storage apparatus in said same storage group, said storage apparatus with the next highest priority after said first storage apparatus or said second storage apparatus subject to a failure takes over said virtualization processing and said data I/O processing of said first storage apparatus, or said internal processing of said second storage apparatus subject to said failure.

11. A data processing method of a storage system in which a plurality of storage apparatuses are connected to a network,

wherein each of said storage apparatuses includes:

a first step where each of said storage apparatuses stores management information per storage apparatus of each of said storage apparatuses configured in the same storage group, and group configuration information formed from management information relating to the overall storage group; and

a second step where the corresponding storage apparatus executes necessary processing based on said group configuration information;

wherein said group configuration information contains priority information representing the priority of each of said storage apparatuses in said storage group given to each of said storage apparatuses belonging to said storage group; and

wherein, at said second step, virtualization processing where a first storage apparatus with the highest priority in said storage group recognized based on said group configuration information becomes a master and virtualizes a storage area to be provided respectively by each of said storage apparatuses, and data I/O processing in reply to a data I/O request from a host system to said virtualized storage area are performed; and

another storage apparatus belonging to said storage performs the internal processing of said storage group.

14. A storage apparatus for providing a storage area for storing data, comprising:

a storage unit for storing management information per storage apparatus of each of said storage apparatuses configured in the same storage group, and group configuration information formed from management information relating to the overall storage group; and

a processing execution unit for executing necessary processing based on said group configuration information;

wherein said group configuration information contains priority information representing the priority of each of said storage apparatuses in said storage group given to each of said storage apparatuses belonging to said storage group; and

wherein said processing execution unit performs virtualization processing for virtualizing each of said storage apparatuses belonging to said storage group when said priority of the own storage apparatus in said storage group recognized based on said group configuration information is the highest, and data I/O processing in reply to a data I/O request from a host system to each of said virtualized storage apparatuses; and

performs internal processing of said storage group when said priority of the own storage apparatus is the next highest priority.