POINT-IN-TIME BACKUPS OF A PRODUCTION APPLICATION MADE ACCESSIBLE OVER FIBRE CHANNEL AND/OR ISCSI AS DATA SOURCES TO A REMOTE APPLICATION BY REPRESENTING THE BACKUPS AS PSEUDO-DISKS OPERATING APART FROM THE PRODUCTION APPLICATION AND ITS HOST

• US 20160154709A1
• Filed: 02/03/2016
• Published: 06/02/2016
• Est. Priority Date: 08/06/2014
• Status: Active Grant

• Current Assignee: CommVault Systems Incorporated, Samsung Electronics Co. Ltd.
• Original Assignee: CommVault Systems Incorporated
• Inventors: Mitkar, Amit, Kumarasamy, Paramasivam
• Granted Patent: US 10,360,110 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 11/00 Error detection; Error correction; Monitoring error detection, correction or monitoring in information storage based on relative movement between record carrier and transducer G11B20/18; monitoring, i.e. supervising the progress of recording or reproducing G11B27/36; in static stores G11C29/00
• CPC Class Codes: G06F 11/1451 by selection of backup contents
• CPC Class Codes: G06F 11/1456 Hardware arrangements for backup
• CPC Class Codes: G06F 11/1464 for networked environments
• CPC Class Codes: G06F 11/1466 to make the backup process non-disruptive
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 11/3034 where the computing system component is a storage system, e.g. DASD based or network based digital input from or digital output to record carriers G06F3/06; digital recording or reproducing G11B20/18; 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], H04L67/1097
• CPC Class Codes: G06F 11/3664 Environments for testing or debugging software
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data
• CPC Class Codes: G06F 3/06 Digital input from, or digital output to, record carriers , e.g. RAID, emulated record carriers or networked record carriers
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06

Abstract

The present enhancement leaves production systems undisturbed while a remote application (“testbed application”) executes elsewhere (“testbed host”). An intermediary computing device hosts an enhanced pseudo-disk driver, pseudo-disks, and an enhanced media agent. The enhanced pseudo-disk driver creates the pseudo-disks, each one representing an associated point-in-time backup image residing in secondary storage. A network, e.g., an Internet Protocol (IP) network or a Fibre Channel (FC) Storage Area Network (SAN), connects the intermediary device with the testbed host, and the enhanced media agent exposes pseudo-disks over the network using iSCSI or FC protocol, respectively. The testbed application uses an exposed pseudo-disk as its recovery data source, such that pseudo-disk resources provide data on an as-needed basis sufficient for the testbed application to operate, yet (a) without restoring the entire associated backup image from secondary storage and (b) without impacting the production environment.

Claims

1. A method for executing an application in a storage management system apart from a production environment, the method comprising:

storing a secondary copy to a secondary storage device that is in communication with a secondary storage computing device,

wherein the secondary copy is a block-level point-in-time backup of primary data for a first application that operates on a client computing device in the production environment,

wherein the secondary storage computing device hosts a media agent and a pseudo-disk driver, and

wherein the secondary storage computing device is in communication over a network with a host computing device that hosts a second application;

instructing, by the media agent, the pseudo-disk driver to generate a pseudo-disk corresponding to the secondary copy;

generating the pseudo-disk on the secondary storage computing device, by the pseudo-disk driver,

wherein the generating comprises creating (i) a first data structure for storing data recalled from the secondary copy, (ii) a second data structure for storing data written by the second application, and (iii) an input-output buffer for receiving read and write requests from the second application and for responding thereto, and

wherein the generating further comprises associating the pseudo-disk with the secondary copy;

exposing the pseudo-disk as a SCSI storage device over the network to the host computing device;

executing the second application on the host computing device using the exposed pseudo-disk as the second application'"'"'s recovery point,

wherein data written by the second application is stored to the second data structure of the pseudo-disk; and

wherein the second application uses the pseudo-disk without restoring the secondary copy in its entirety from the secondary storage device.

2. The method of claim 1 wherein data read requests issued by the executing second application are satisfied by the pseudo-disk by (a) retrieving the requested data from the second data structure;

and

if the requested data cannot be found in the second data structure, by (b) retrieving the requested data from the first data structure; and

if the requested data cannot be found in the first data structure, by (c) retrieving the requested data from the secondary copy to the first data structure and serving the data read request therefrom.

3. The method of claim 1 wherein the second application executes on the host computing device without impacting the first application, without impacting the client computing device, and without impacting the production environment.

4. The method of claim 1 wherein the instructing by the media agent comprises information about a backup job in the storage management system that generated the secondary copy, and wherein the pseudo-disk is associated with the backup job.

5. The method of claim 1 wherein the pseudo-disk comprises a pointer to the secondary copy stored in the secondary storage device.

6. The method of claim 1 wherein the second application uses pseudo-disk resources, including the first data structure and the second data structure, to operate based on as-needed data without initiating a restore of the entire secondary copy from the secondary storage device.

7. The method of claim 1 wherein the host computing device is distinct and apart from the client computing device, and wherein the second application executes on the host computing device using the exposed pseudo-disk on the secondary storage computing device, apart from the production environment that includes the client computing device.

8. The method of claim 1 wherein the pseudo-disk is exposed using iSCSI protocol.

9. The method of claim 1 wherein the pseudo-disk is exposed using Fibre Channel protocol.

10. A storage management system comprising:

a primary storage subsystem that comprises a primary application executing on a client computing device, wherein the application accesses primary data on a primary storage device;

a secondary storage device storing a secondary copy of the primary data, wherein the secondary copy is a point-in-time block-level backup of the primary data;

a secondary storage computing device that hosts (i) a media agent that acts as a data access portal to the secondary storage device and the secondary copy stored thereon, and (ii) a pseudo-disk created by a pseudo-disk driver, wherein the pseudo-disk points to the secondary copy;

a host computing device in communication with the secondary storage computing device over a network,

wherein the pseudo-disk is exposed over the network to the host computing device as a SCSI storage device; and

a secondary application executing on the host computing device,

wherein the secondary application is logically attached to the pseudo-disk as a recovery data source for the secondary application, and

wherein the second application uses the pseudo-disk to access data as needed without restoring the secondary copy in its entirety from the secondary storage device.

11. The storage management system of claim 10 wherein the pseudo-disk comprises:

(a) a first data structure for storing data recalled from the secondary copy in response to some data read requests received from the secondary application,

(b) a second data structure for storing data written by the secondary application, and

(c) an input-output buffer for receiving read and write requests from the secondary application and for responding thereto.

12. The storage management system of claim 11 wherein data read requests issued by the secondary application are satisfied by the pseudo-disk by (A) retrieving the requested data from the second data structure;

and

if the requested data cannot be found in the second data structure, by (B) retrieving the requested data from the first data structure; and

if the requested data cannot be found in the first data structure, by (C) retrieving the requested data from the secondary copy to the first data structure and serving the data read request therefrom.

13. The storage management system of claim 10 wherein the pseudo-disk driver also resides on the secondary storage computing device;

and

wherein the media agent is configured to instruct the pseudo-disk driver to create the pseudo-disk and to associate the pseudo-disk with the secondary copy after the media agent is involved in storing the secondary copy to the secondary storage device.

14. A computer-readable medium, excluding transitory propagating signals, storing instructions that, when executed by at least one secondary storage computing device, cause the secondary storage computing device to perform operations comprising:

storing a secondary copy to a secondary storage device that is in communication with a secondary storage computing device,

wherein the secondary copy is a block-level point-in-time backup of primary data for a first application that operates on a client computing device;

hosting a media agent and a pseudo-disk driver;

communicating over a network with a host computing device that hosts a second application, wherein the host computing device is distinct and apart from the client computing device;

after storing the secondary copy to the secondary storage device, causing the pseudo-disk driver to generate a pseudo-disk corresponding to and associated with the secondary copy, wherein the pseudo-disk comprises (i) a first data structure for storing data retrieved from the secondary copy, (ii) a second data structure for storing data written by the second application, and (iii) an input-output buffer for receiving read and write requests from the second application and for responding thereto; and

exposing the pseudo-disk as a SCSI storage device over the network to the host computing device, thereby enabling the second application to attach to the exposed pseudo-disk and to use the exposed pseudo-disk as pseudo-disk as a recovery data source for the second application without restoring the secondary copy in its entirety from the secondary storage device.

15. The computer-readable medium of claim 14 wherein the operations further comprise:

storing data written by the second application to the second data structure of the pseudo-disk; and

serving data read requests received from the second application by (a) retrieving requested data from the second data structure of the pseudo-disk, and

if the requested data cannot be found in the second data structure, by (b) retrieving the requested data from the first data structure, and

if the requested data cannot be found in the first data structure, by (c) retrieving the requested data from the secondary copy to the first data structure and serving the requested data therefrom.

16. The computer-readable medium of claim 14 wherein the media agent is configured to instruct the pseudo-disk driver to create the pseudo-disk and to associate the pseudo-disk with the secondary copy after the media agent is involved in storing the secondary copy to the secondary storage device.

17. The computer-readable medium of claim 14 wherein the secondary storage computing device and the host computing device operate in conjunction with each other to enable the second application to execute using the pseudo-disk without impacting or interacting with the first application, the primary data, and the client computing device.