METHOD AND SYSTEM FOR VIRTUAL ON-DEMAND RECOVERY

• US 20120266019A1
• Filed: 06/27/2012
• Published: 10/18/2012
• Est. Priority Date: 07/20/2005
• Status: Active Grant

• Current Assignee: Quest Software, Inc.
• Original Assignee: Quest Software, Inc.
• Inventors: Sim-Tang, Siew Yong
• Granted Patent: US 8,365,017 B2
• Time in Patent Office: Days
• US Class Current: 714/21
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 11/1471 involving logging of persistent data for recovery
• CPC Class Codes: G06F 11/2094 Redundant storage or storage space G06F11/2056 takes precedence
• CPC Class Codes: G06F 11/2097 maintaining the standby controller/processing unit updated initialisation or re-synchronisation thereof G06F11/1658 and subgroups
• CPC Class Codes: G06F 2201/82 Solving problems relating to consistency ensuring consistency in mirrored systems G06F11/2064
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data

Abstract

A data management system (“DMS”) provides an automated, continuous, real-time, substantially no downtime data protection service to one or more data sources. A host driver embedded in an application server captures real-time data transactions, preferably in the form of an event journal. The driver functions to translate traditional file/database/block I/O and the like into a continuous, application-aware, output data stream. The host driver includes an event processor that can perform a recovery operation to an entire data source or a subset of the data source using former point-in-time data in the DMS. The recovery operation may have two phases. First, the structure of the host data in primary storage is recovered to the intended recovering point-in-time. Thereafter, the actual data itself is recovered. The event processor enables such data recovery in an on-demand manner, by allowing recovery to happen simultaneously while an application accesses and updates the recovering data.

Claims

1. A method of data recovery in a first computer processing environment, where data has been stored in a data store different from a data source in the first processing environment, the method comprising:

initiating a data recovery operation;

recovering given data to a former state as reflected in a data store, wherein the recovery comprises;

presenting a structure of the given data to a user associated with a database so that, from a point-of-view of the user, the database is recovered prior to fully recovering the given data;

if an access request is for data that has not been recovered, promptly recovering the data requested; and

continuing to recover the given data; and

enabling a database application to continue accessing or updating the given data during the recovery.

2. The method of claim 1, wherein presenting the structure of the given data comprises creating a sorted data list for the given data from information in the data store.

3. The method of claim 2, further comprising:

if a structure of the data requested or actual data for the data requested does not exist in the sorted data list, sending a recover request for the data requested to the data store.

4. The method of claim 3, wherein sending the recover request comprises:

if the data requested exists in the database, computing checksums and sending the recover request only for deltas of the data requested from the data store.

5. The method of claim 2, wherein enabling the database application to continue updating the given data during the recovery comprises capturing database application events.

6. The method of claim 5, further comprising updating the data store with the database events.

7. The method of claim 1, further comprising filtering access requests during presenting the structure of the given data.

8. The method of claim 5, further comprising marking, in the sorted data list, a given data item as recovered if the captured database events comprise information associated with the given data item.

9. An apparatus for providing a data recovery service in a first processing environment, where data has been stored in a data store different from a data source in the first processing environment, comprising:

a processor; and

code executable by the processor to;

initiate a data recovery operation;

recover given data to a former state as reflected in a data store, wherein the recovery comprises;

presenting a structure of the given data to a user associated with a database so that, from a point-of-view of the user, the database is recovered prior to fully recovering the given data;

if an access request is for data that has not been recovered, promptly recovering the data requested; and

continuing to recover the given data; and

enable a database application to continue accessing or updating the given data during the recovery.

10. The apparatus of claim 9, wherein presenting the structure of the given data comprises creating a sorted data list for the given data from information in the data store.

11. The apparatus of claim 10, wherein the code executable by the processor further comprises:

if a structure of the data requested or actual data for the data requested does not exist in the sorted data list, sending a recover request for the data requested to the data store.

12. The apparatus of claim 11, wherein sending the recover request comprises:

if the data requested exists in the database, computing checksums and sending the recover request only for deltas of the data requested from the data store.

13. The apparatus of claim 10, wherein enabling the database application to continue updating the given data during the recovery comprises capturing database application events.

14. The apparatus of claim 10, further comprising a host driver that captures database application events to enable the database application to continue updating the given data during the recovery.

15. The apparatus of claim 10, further comprising a filter driver, wherein the filter driver captures database application events to enable the database application to continue updating the given data during the recovery.

16. The apparatus of claim 13, wherein the code executable by the processor further comprises updating the data store with the database events.

17. The apparatus of claim 9, wherein the code executable by the processor further comprises filtering access requests during presenting the structure of the given data.

18. The apparatus of claim 13, wherein the code executable by the processor further comprises marking, in the sorted data list, a given data item as recovered if the captured database events comprise information associated with the given data item.

19. The apparatus of claim 9, further comprising an interface where a recovery command is entered to initiate the data recovery operation.