Using metadata extracted from proxy files to access data stored in secondary storage

• US 10,303,562 B2
• Filed: 06/29/2017
• Issued: 05/28/2019
• Est. Priority Date: 03/30/2017
• Status: Active Grant

• Current Assignee: Micro Focus LLC (Open Text Corporation)
• Original Assignee: entIT Software LLC (Open Text Corporation)
• Inventors: Nanivadekar, Mandar
• Primary Examiner(s): Contino, Paul
• Application Number:
  US15/638,040
• Publication Number:
  US 20180285212A1
• Time in Patent Office: 698 Days
• CPC Class Codes: G06F 11/1451 by selection of backup contents
• CPC Class Codes: G06F 11/1464 for networked environments
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 16/128 Details of file system snapshots on the file-level, e.g. snapshot creation, administration, deletion use of snapshots for error detection or correction G06F11/14, G06F11/16
• CPC Class Codes: G06F 16/16 File or folder operations, e.g. details of user interfaces specifically adapted to file systems
• CPC Class Codes: G06F 16/188 Virtual 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 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• 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 technique includes creating a proxy file that is associated with a recovery request, which is associated with the recovery of data associated with a virtual machine file from a secondary storage. The technique includes using metadata that is extracted from the proxy file to access the data. Using the metadata includes, in response to an input/output (I/O) request associated with the recovery request, storing an association of an identifier of the proxy file with metadata representing a parameter associated with the secondary storage. The metadata is stored outside the proxy file. The metadata is used to identify an I/O processing unit; and the technique includes communicating with the I/O processing unit to notify the I/O processing unit to process the I/O request.

Claims

1. A method comprising:

in response to a recovery request to recover data associated with a virtual machine file, creating a proxy file, wherein the virtual machine file is associated with a virtual machine, and the proxy file has a file format recognized by a hypervisor for the virtual machine;

extracting metadata from the proxy file representing a parameter associated with a secondary storage;

storing the extracted metadata outside of the proxy file;

associating the extracted metadata with an identifier; and

in response to an input/output (I/O) request associated with the recovery request, retrieving the extracted metadata to determine the parameter based on the identifier of the proxy file and processing the I/O request based on the determined parameter.

2. The method of claim 1, wherein the parameter represents at least one of a location of the data in a storage device of the secondary storage or a credential of a host processing the I/O request.

3. The method of claim 1, wherein extracting the metadata from the proxy file comprises extracting the metadata in response to processing another I/O request associated with the recovery request.

4. The method of claim 1, further comprising:

creating a logical processing unit to process the I/O request associated with the recovery request;

associating the logical processing unit with a data repository; and

using the logical processing unit to retrieve data from the data repository in response to the I/O request in lieu of retrieving the data from the secondary storage.

5. The method of claim 4, further comprising:

sizing the data repository based on a characteristic of the recovery request.

6. The method of claim 1, wherein the I/O request targets first data stored in the secondary storage, the method further comprising:

creating a logical processing unit to process the I/O request associated with the recovery request;

associating the logical processing unit with a data repository;

using the logical processing unit to perform a block transfer operation to retrieve first data and second data from the secondary storage;

storing the second data in the data repository;

using the logical processing unit to provide the first data in response to the I/O request; and

using the logical processing unit to retrieve at least part of the second data from the data repository and provide the at least part of the second data in response to another I/O request.

7. The method of claim 1, further comprising:

creating a logical processing unit to process the I/O request associated with the recovery request, wherein the I/O request is one of a plurality of I/O requests processed by the logical processing unit and associated with the recovery request;

associating the logical processing unit with a data repository;

the logical processing unit processing the I/O requests, comprising retrieving data from the secondary storage and storing the retrieved data in the data repository; and

the logical processing unit maintaining a data inventory for the data repository.

8. The method of claim 7, further comprising:

the logical processing unit selectively invalidating data in the data inventory based on associated access to the data.

9. The method of claim 1, wherein creating the proxy file comprises creating a thin file.

10. An article comprising a non-transitory storage medium storing instructions, that when executed by a computer, cause the computer to:

create a proxy file associated with a recovery request, wherein the recovery request is associated with the recovery of data associated with a virtual machine file from a secondary storage; and

use metadata extracted from the proxy file to access the data, including, in response to an input/output (I/O) request associated with the recovery request;

storing an association of an identifier of the proxy file with metadata representing a parameter associated with the secondary storage, wherein the metadata is stored outside the proxy file;

using the metadata to identify an I/O logical processing unit; and

communicating with the I/O logical processing unit to notify the I/O logical processing unit to process the I/O request.

11. The article of claim 10, the storage medium storing instructions that, when executed by the computer, cause the computer to:

in response to the recovery request, open a connection with the secondary storage and assign a logical processing unit to the connection;

use the extracted metadata to retrieve an identification of the I/O logical processing unit; and

communicate with the I/O logical processing unit to notify the I/O logical processing unit to process the I/O request.

12. The article of claim 11, the storage medium storing instructions, that when executed by the computer, cause the computer to:

in response to another recovery request, create another proxy file associated with the another recovery request.

13. The article of claim 12, wherein the recovery request comprises a first recovery request, the storage medium storing instructions that, when executed by the computer, cause the computer to:

create a first I/O logical processing unit to process the I/O request associated with the first recovery request; and

create a second I/O logical processing unit to process another I/O request associated with a second recovery request to recover data associated with the virtual machine file.

14. The article of claim 10, wherein the parameter represents a location of the data in a storage device of the secondary storage.

15. The article of claim 10, wherein a host performs the processing of the I/O request, and the parameter represents a credential of the host.

16. An apparatus comprising:

a processor; and

a memory storing instructions that, when executed by the processor, cause the processor to;

create a plurality of proxy files for associated recovery sessions to recover data associated with virtual machine files stored in a secondary storage;

retrieve a plurality of I/O requests; and

for a given I/O request of the plurality of I/O requests referencing a given proxy file;

determine an identifier associated with the given proxy file;

determine whether the given proxy file has been parsed; and

based on a result of the determination of whether the given proxy file has been parsed, selectively parse the proxy file to retrieve metadata representing a parameter of the secondary storage for performing the given I/O request with a storage device of the secondary storage.

17. The apparatus of claim 16, wherein the instructions, when executed by the processor, cause the processor to determine the identifier associated with the proxy file based on an operation time of the processor.

18. The apparatus of claim 16, wherein the instructions, when executed by the processor, cause the processor to provide a lock to prevent other identifiers from being generated during a time interval in which the identifier of the proxy file is being generated.

19. The apparatus of claim 16, wherein the proxy file comprises the metadata representing a connection to the secondary storage and at least one of metadata identifying a version of the proxy file, metadata identifying permission to delete the proxy file and metadata representing permission to write to the proxy file.

20. The apparatus of claim 16, wherein the instructions, when executed by the processor, cause the processor to create a logical processing unit to process I/O requests associated with the given proxy file and associate the identifier with the logical processing unit.