METHOD AND SYSTEM TO EFFICIENTLY RECOVERING A CONSISTENT VIEW OF A FILE SYSTEM IMAGE FROM AN ASYNCHRONOUSLY REMOTE SYSTEM

• US 20200134053A1
• Filed: 10/31/2018
• Published: 04/30/2020
• Est. Priority Date: 10/31/2018
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Inventors: Bhutani, Neeraj, Gunda, Kalyan Chakravarthy, Madan, Nitin, Konduru, Jayasekhar
• Granted Patent: US 10,977,217 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 11/1453 using de-duplication of the data
• CPC Class Codes: G06F 11/2056 by mirroring
• CPC Class Codes: G06F 11/2094 Redundant storage or storage space G06F11/2056 takes precedence
• CPC Class Codes: G06F 16/1748 De-duplication implemented within the file system, e.g. based on file segments de-duplication techniques in storage systems for the management of data blocks G06F3/0641
• CPC Class Codes: G06F 16/178 Techniques for file synchronisation in file systems
• CPC Class Codes: G06F 16/1844 Management specifically adapted to replicated file systems
• CPC Class Codes: G06F 2201/815 Virtual middleware or OS functionality using virtual machines to implement generic software techniques for error detection or fault masking G06F11/1484
• CPC Class Codes: G06F 2201/82 Solving problems relating to consistency ensuring consistency in mirrored systems G06F11/2064
• 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 3/0641 De-duplication techniques
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]

Abstract

A method for managing storage devices includes, in response to a first determination that a first cloud storage device is inaccessible to a local storage device, obtaining metadata objects from a second cloud storage device, identifying, based on a sync time analysis, at least one metadata object of the metadata objects to be deleted, initiating the deletion of the at least one metadata object on a second cloud storage device, wherein the second cloud storage device is accessible to the local storage device, and updating, after initiating the deletion of the at least one metadata object, a namespace on a local storage device.

Claims

1. A method for managing storage devices, the method comprising:

in response to a first determination that a first cloud storage device is inaccessible to a local storage device, obtaining metadata objects from a second cloud storage device;

identifying, based on a sync time analysis, at least one metadata object of the metadata objects to be deleted;

initiating the deletion of the at least one metadata object on a second cloud storage device, wherein the second cloud storage device is accessible to the local storage device; and

updating, after initiating the deletion of the at least one metadata object, a namespace on a local storage device.

2. The method of claim 1, further comprising:

prior to the first determination, migrating data from the local storage to the first cloud storage, wherein at least a portion of the data is replicated on the second cloud storage, wherein the local storage device does not participate in the replication of the at least a portion of the data.

3. The method of claim 2,

wherein the data comprises a metadata object and a data object,

wherein the metadata object and the data object as associated with a file, wherein the file is received by the local storage device from a client.

4. The method of claim 3, wherein the metadata object and the data object are generated by deduplicating the data.

5. The method of claim 1, wherein the sync time analysis comprises using a most recent sync time to determine that the at least one metadata object is to be deleted from the second cloud storage device.

6. The method of claim 5, wherein the most recent sync time corresponds to a time at which the same metadata objects and data objects are stored on both the first cloud storage device and the second cloud storage device.

7. The method of claim 1, wherein updating the namespace on the local storage devices comprises deleting a file identifier associated with the at least one metadata object.

8. A local storage device, comprising:

a processor;

memory comprising instructions, which when executed by the processor, perform a method, the method comprising;

in response to a first determination that a first cloud storage device is inaccessible to a local storage device, obtaining metadata objects from a second cloud storage device;

identifying, based on a sync time analysis, at least one metadata object of the metadata objects to be deleted;

initiating the deletion of the at least one metadata object on a second cloud storage device, wherein the second cloud storage device is accessible to the local storage device; and

updating, after initiating the deletion of the at least one metadata object, a namespace on a local storage device.

9. The local storage device of claim 8, the method further comprising:

prior to the first determination, migrating data from the local storage to the first cloud storage, wherein at least a portion of the data is replicated on the second cloud storage, wherein the local storage device does not participate in the replication of the at least a portion of the data.

10. The local storage device of claim 9,

wherein the data comprises a metadata object and a data object,

wherein the metadata object and the data object as associated with a file, wherein the file is received by the local storage device from a client,

wherein the metadata object and the data object are generated by deduplicating the data.

11. The local storage device of claim 8, wherein the sync time analysis comprises using a most recent sync time to determine that the at least one metadata object is to be deleted from the second cloud storage device.

12. The local storage device of claim 11, wherein the most recent sync time corresponds to a time at which the same metadata objects and data objects are stored on both the first cloud storage device and the second cloud storage device.

13. The local storage device of claim 8, wherein updating the namespace on the local storage devices comprises deleting a file identifier associated with the at least one metadata object.

14. A non-transitory computer readable medium comprising computer readable program code, which when executed by a computer processor enables the computer processor to perform a method, the method comprising:

in response to a first determination that a first cloud storage device is inaccessible to a local storage device, obtaining metadata objects from a second cloud storage device;

identifying, based on a sync time analysis, at least one metadata object of the metadata objects to be deleted;

initiating the deletion of the at least one metadata object on a second cloud storage device, wherein the second cloud storage device is accessible to the local storage device; and

updating, after initiating the deletion of the at least one metadata object, a namespace on a local storage device.

15. The non-transitory computer readable medium of claim 14, the method further comprising:

prior to the first determination, migrating data from the local storage to the first cloud storage, wherein at least a portion of the data is replicated on the second cloud storage, wherein the local storage device does not participate in the replication of the at least a portion of the data.

16. The non-transitory computer readable medium of claim 15,

wherein the data comprises a metadata object and a data object,

wherein the metadata object and the data object as associated with a file, wherein the file is received by the local storage device from a client.

17. The non-transitory computer readable medium of claim 16, wherein the metadata object and the data object are generated by deduplicating the data.

18. The non-transitory computer readable medium of claim 14, wherein the sync time analysis using a most recent sync time to determine that the at least one metadata object is to be deleted from the second cloud storage device.

19. The non-transitory computer readable medium of claim 18, wherein the most recent sync time corresponds to a time at which the same metadata objects and data objects are stored on both the first cloud storage device and the second cloud storage device.

20. The non-transitory computer readable medium of claim 14, wherein updating the namespace on the local storage devices comprises deleting a file identifier associated with the at least one metadata object.