Systems and methods for backing up data files

• US 6,460,055 B1
• Filed: 12/16/1999
• Issued: 10/01/2002
• Est. Priority Date: 12/16/1999
• Status: Expired due to Term

• Current Assignee: Keepitsafe
• Original Assignee: LiveVault Corp. (Iron Mountain Incorporated)
• Inventors: Wilson, Brian, Webb, John, Hansen, Tom, Midgley, Christopher, Hess, Ted, Acott, John
• Primary Examiner(s): Alam, Hosain T.
• Assistant Examiner(s): ALAM, SHAHID AL
• Application Number:
  US09/465,485
• Time in Patent Office: 1,020 Days
• Field of Search: 707/1, 707/8, 707/10, 707/100, 707/200-206, 707/103.R, 707/104.1, 709/212, 709/214, 709/219, 709/249, 709/221, 709/228, 709/236, 711/111, 711/112, 711/114, 711/162, 714/4, 714/5, 714/6, 714/20, 714/21, 713/176
• US Class Current: 707/640
• CPC Class Codes: G06F 11/1461 Backup scheduling policy
• CPC Class Codes: G06F 11/2058 using more than 2 mirrored copies
• CPC Class Codes: G06F 11/2064 while ensuring consistency
• CPC Class Codes: G06F 11/2071 using a plurality of controllers
• CPC Class Codes: G06F 2201/855 Details of asynchronous mirroring using a journal to transfer not-yet-mirrored changes
• CPC Class Codes: Y10S 707/99938 Concurrency, e.g. lock management in shared database
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

The invention provides systems and methods for continuous back up of data stored on a computer network. To this end the systems of the invention include a synchronization process that replicates selected source data files data stored on the network and to create a corresponding set of replicated data files, called the target data files, that are stored on a back up server. This synchronization process builds a baseline data structure of target data files. In parallel to this synchronization process, the system includes a dynamic replication process that includes a plurality of agents, each of which monitors a portion of the source data files to detect and capture, at the byte-level, changes to the source data files. Each agent may record the changes to a respective journal file, and as the dynamic replication process detects that the journal files contain data, the journal files are transferred or copied to the back up server so that the captured changes can be written to the appropriate ones of the target data files.

Claims

1. A system for creating back up files for data files stored on a computer network, comprising

a back up server having a target data file,

a data server having

a source data file associated with the target data file, and

an agent operating on the data server for capturing and recording changes to the source data file as the source data file is being modified and for detecting and recording safe points capable of identifying one or more of the recorded changes as part of a related transaction,

a dynamic replication process for transmitting a journal file from the data server to the back up server and capable of processing the journal file for altering the target data file to mirror changes made to the source data file, and

a transaction processor for processing the safe points to direct the operation of the dynamic replication process to alter the target data file as a function of the identified transaction.

2. A system according to claim 1, wherein the agent includes a time stamp process for writing to the journal file a time and date signal representative of a time and date of a recorded change to the source data file.

3. A system according to claim 1, wherein the agent process includes a process for checking the open status of the source data file for writing in the journal file a file closed signal representative of detecting a file close status for the source data file.

4. A system according to claim 1, wherein the transaction processor includes a timer process for writing a safe point signal to the journal file in response to an indication the data source file has been inactive for a predetermined period of time.

5. A system according to claim 1, wherein the agent process includes a lock detect process for writing a lock detect signal to the journal file in response to an indication a file/record locking status is set off the data source file.

6. A system according to claim 1, wherein the agent process includes a flush detect process for writing a flush signal to the journal file in response to an indication a flush operation has been performed for the data source file.

7. A system according to claim 1, wherein the agent process includes a user selection process for writing a safe point signal to the journal file in response to a user command to place a safe point marker in the journal file.

8. A system according to any of claims 3, 4, 5, 6 or 7 wherein the transaction processor processes safe points within the journal file to prioritize the identified transactions to select a transaction for altering the source file.

9. A system according to claim 1, further including a policy manager for placing safe points within a plurality of journal files for coordinating the operation of the transaction processor to process plural target files as a single logical unit of data.

10. A system according to claim 1, wherein the transaction processor includes a timer process for processing journal files at a predetermined interval.

11. A system according to claim 10, wherein the transaction processor directs the dynamic replication process to write changes at predetermined intervals to target data files having corresponding source data files with a closed file status.

12. A system according to claim 1, wherein the transaction processor directs the dynamic replication process to write changes to the target data file based on an indication of a file/record locking status set off for the data source file.

13. A system according to claim 1, wherein the transaction processor directs the dynamic replication process to write changes to the target data file based on an indication of a flush operation has been performed for the data source file.

14. A system according to claim 1, wherein the transaction processor directs the dynamic replication process to write changes to the target data file based on an indication of a user command to place a safe point marker in the journal file.

15. A system according to claim 1, further including a back up service responsive to a safe point in the journal file, for storing the target file on a long term storage medium.

16. A system according to claim 1, including a catalog process for time-stamping to a catalog file a time signal for indicating the date/time of a most recent transaction that was written to a target data file or a plurality of target data files.

17. A system according to claim 16, further comprising a restore process for restoring selecting target data files as a function of the time stamp signal, to allow a user to employ time and date information for restoring data to the source data file or a plurality of source data files.

18. A system according to claim 16, wherein there are a plurality of source data files and target data files, the system including a time-slice processor, for allowing the user to employ time information for restoring a group of the target data files as a function of the time signal.

19. A system according to claim 1, wherein the agent process includes a process for allowing a computer process to write a safe point signal to the journal file.