Pathname translation in a data replication system

• US 7,636,743 B2
• Filed: 12/18/2006
• Issued: 12/22/2009
• Est. Priority Date: 12/19/2005
• Status: Active Grant

• Current Assignee: CommVault Systems Incorporated
• Original Assignee: CommVault Systems Incorporated
• Inventors: Erofeev, Andrei
• Primary Examiner(s): To; Baoquoc N
• Application Number:
  US11/640,830
• Publication Number:
  US 20070185852A1
• Time in Patent Office: 1,100 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G06F 16/166 File name conversion
• CPC Class Codes: G06F 16/184 implemented as replicated file system
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

Performing data management operations on replicated data in a computer network. Log entries are generated for data management operations of an application executing on a source system. Consistency point entries are used to indicate a time of a known good, or recoverable, state of the application. A destination system is configured to process a copy of the log and consistency point entries to replicate data in a replication volume, the replicated data being a copy of the application data on the source system. When the replicated data represents a known good state of the application, as determined by the consistency point entries, the destination system(s) may perform a storage operation (e.g., snapshot, backup) to copy the replicated data and to logically associate the copied data with a time information (e.g., time stamp) indicative of the source system time when the application was in the known good state.

Claims

1. A method for performing pathname translation in a data replication system, the method comprising:

storing log entries in a first log file on a source system;

copying at least a portion of the log entries to a second log file on a destination system;

processing the log entries in the second log file to create replicated data on a destination system, wherein one or more of the log entries identify a data management operation and an inode associated with a source system location corresponding to the data management operation, the inode being one of a plurality of inodes on the source system;

storing in a database on the destination system, a short inode name and a parent inode name for at least a first inode identified by the log entries in the second log file;

processing a log entry from the second log file on the destination device that identifies a second inode, wherein the first inode is the parent of the second inode;

accessing the database on the destination system to obtain path data for the second inode based on the short inode name and the parent inode name of the first inode stored in the database;

constructing from the path data an absolute pathname on the destination system that corresponds to the second inode of the log entry in the second log file.

2. The method of claim 1, wherein said accessing and constructing are performed in an application space external to a kernel space of the source system.

3. The method of claim 1, additionally comprising generating the log entry in the first log file with a filter driver.

4. The method of claim 1, additionally comprising modifying the short name of a third inode of the plurality of inodes.

5. The method of claim 4, wherein said modifying comprises modifying a single entry in the database.

6. The method of claim 1, wherein said accessing is performed by a single database process for a plurality of received log entries.

7. The method of claim 1, additionally comprising populating the database with the path data.

8. The method of claim 7, wherein said populating comprises recording a static image of a file system of the source system.

9. A system for performing pathname translation during data replication in a computer network, the system comprising:

a first log file of log entries, wherein the first log file is stored on a source system;

a second log file of log entries that comprises copies of at least a portion of the first log entries in the first log file, wherein the second log file is stored on a destination system;

a database stored on the destination system comprising path data that associates each of a plurality of inodes on a source system with a short name and a parent inode;

at least one log entry in the second log file on the destination system identifying a data management operation and at least one corresponding inode of the plurality of inodes; and

a database process on the destination system configured to access the database to translate the at least one corresponding inode to a pathname identifying a location on a destination system corresponding to the data management operation.

10. The system of claim 9, wherein the pathname comprises a fully qualified pathname.

11. The system of claim 9, wherein the database comprises a multi-column database.

12. The system of claim 11, wherein the database comprises an inode column, a short name column and a parent inode column.

13. The system of claim 9, wherein the database is configured to be accessible by only the single database process.

14. The system of claim 9, wherein the database process is further configured to send to one or more destination systems the at least one log entry with the pathname in place of the at least one corresponding inode.

15. The system of claim 9, further comprising a filter driver configured to generate the at least one log entry for the first log file.

16. The system of claim 9, wherein the plurality of inodes corresponds to source system data structures associated with data of a single computer application.

17. The system of claim 16, further comprising a second database comprising second path data that associates each of a second plurality of inodes that corresponds to the source system data structures associated with data of the second computer application.