System and method for negotiated takeover of storage objects

• US 9,424,301 B2
• Filed: 11/22/2013
• Issued: 08/23/2016
• Est. Priority Date: 11/22/2013
• Status: Active Grant

• Current Assignee: NetApp, Inc.
• Original Assignee: NetApp, Inc.
• Inventors: Dhavale, Poonam, Bhuwania, Manish, Ramachandran, Arun, Mutiso, Herman M.
• Primary Examiner(s): LEWIS, CHERYL RENEA
• Application Number:
  US14/088,196
• Publication Number:
  US 20150149416A1
• Time in Patent Office: 1,005 Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/2308 Concurrency control transaction processing G06F9/466

Abstract

A system and method of negotiated takeover of storage objects includes one or more processors, a storage controller, and memory coupled to the one or more processors. The memory stores a data structure that includes information about a plurality of storage objects manageable by the storage controller. The storage controller is configured to assume, one by one, current ownership of a first subset of the storage objects and assume, concurrently, current ownership of a second subset of the storage objects. The first subset of storage objects and the second subset of storage objects are currently owned by a second storage server coupled to the storage server. In some embodiments, current ownership of the first subset of storage objects is transferred by iteratively detecting a particular storage object from the first subset of the storage objects whose current ownership can be assumed and bringing the particular storage object online.

Claims

1. A target storage server comprising:

memory containing machine readable medium comprising machine executable code having stored thereon instructions for storage object management and storing a data structure including information about a plurality of storage objects; and

a processor coupled to the memory, the processor configured to execute the machine executable code to cause the processor to;

send a takeover message to a source storage server, detect a particular storage object from a first subset of the storage objects that is currently owned by the source storage server and whose ownership can be assumed based on the data structure, bring the particular storage object online, and iteratively detect and bring online additional of the first subset of the storage objects until the source storage server indicates that there are no more storage objects within the first subset of the storage objects to be taken over; and

assume, concurrently, current ownership of a second subset of the storage objects, wherein the second subset of the storage objects is currently owned by the source storage server.

2. The target storage server of claim 1 wherein the processor is further configured to execute the machine executable code to receive a source done message from the source storage server to detect the particular storage object, the source done message including an identifier associated with the particular storage object.

3. The target storage server of claim 1 wherein the processor is further configured to execute the machine executable code to receive a relocation done message from the source storage server to indicate that there are no more storage objects within the first subset of the storage objects to be taken over.

4. The target storage server of claim 1 wherein the processor is further configured to execute the machine executable code to send a storage object online message to the source storage server after bringing the particular storage object online, the storage object online message including an identifier associated with the particular storage object.

5. The target storage server of claim 1 wherein the processor is further configured to execute the machine executable code to:

send a shutdown message to the source storage server;

receive a shutdown done message from the source storage server;

detect the second subset of the storage objects by scanning the data structure of storage objects;

change current ownership of the second subset of the storage objects; and

bring each storage object in the second subset of the storage objects online.

6. The target storage server of claim 5 wherein the processor is further configured to execute the machine executable code to:

start a timer after sending the shutdown message; and

detect the second subset of the storage objects when the timer times out.

7. A non-transitory machine readable medium having stored thereon instructions for performing a method comprising machine executable code which when executed by a target storage server, causes the target storage server to:

send a takeover message to a source storage server, detect a particular storage object from a first subset of a plurality of storage objects that is currently owned by the source storage server and whose ownership can be assumed based on a data structure including information about the storage objects, bring the particular storage object online, and iteratively detect and bring online additional of the first subset of the storage objects until the source storage server indicates that there are no more storage objects within the first subset of the storage objects to be taken over; and

assume, concurrently, current ownership of a second subset of the storage objects, wherein the second subset of the storage objects is currently owned by the source storage server.

8. The non-transitory machine readable medium of claim 7, wherein the machine executable code when executed by the target storage server further causes the target storage server to receive a source done message from the source storage server to detect the particular storage object, the source done message including an identifier associated with the particular storage object.

9. The non-transitory machine readable medium of claim 7, wherein the machine executable code when executed by the target storage server further causes the target storage server to receive a relocation done message from the source storage server to indicate that there are no more storage objects within the first subset of the storage objects to be taken over.

10. The non-transitory machine readable medium of claim 7, wherein the machine executable code when executed by the target storage server further causes the target storage server to send a storage object online message to the source storage server after bringing the particular storage object online, the storage object online message including an identifier associated with the particular storage object.

11. The non-transitory machine readable medium of claim 7, wherein the machine executable code when executed by the target storage server further causes the target storage server to:

send a shutdown message to the source storage server;

receive a shutdown done message from the source storage server;

detect the second subset of the storage objects by scanning the data structure of storage objects;

change current ownership of the second subset of the storage objects; and

bring each storage object in the second subset of the storage objects online.

12. The non-transitory machine readable medium of claim 11, wherein the machine executable code when executed by the target storage server further causes the target storage server to:

start a timer after sending the shutdown message; and

detect the second subset of the storage objects when the timer times out.

13. A method, comprising:

sending, by a target storage server, a takeover message to a source storage server, detecting a particular storage object from a first subset of a plurality of storage objects that is currently owned by the source storage server and whose ownership can be assumed based on a data structure including information about the storage objects, bringing the particular storage object online, and iteratively detecting and bringing online additional of the first subset of the storage objects until the source storage server indicates that there are no more storage objects within the first subset of the storage objects to be taken over; and

assuming, concurrently and by the target storage server, current ownership of a second subset of the storage objects, wherein the second subset of the storage objects is currently owned by the source storage server.

14. The method of claim 13, further comprising receiving, by the target storage server, a source done message from the source storage server to detect the particular storage object, the source done message including an identifier associated with the particular storage object.

15. The method of claim 13, further comprising receiving, by the target storage server, a relocation done message from the source storage server to indicate that there are no more storage objects within the first subset of the storage objects to be taken over.

16. The method of claim 13, further comprising sending, by the target storage server, a storage object online message to the source storage server after bringing the particular storage object online, the storage object online message including an identifier associated with the particular storage object.

17. The method of claim 13, further comprising:

sending, by the target storage server, a shutdown message to the source storage server;

receive, by the target storage server, a shutdown done message from the source storage server;

detecting, by the target storage server, the second subset of the storage objects by scanning the data structure of storage objects;

changing, by the target storage server, current ownership of the second subset of the storage objects; and

bringing, by the target storage server, each storage object in the second subset of the storage objects online.

18. The method of claim 17, further comprising:

starting, by the target storage server, a timer after sending the shutdown message; and

detecting, by the target storage server, the second subset of the storage objects when the timer times out.