Method for managing multiple file states for replicated files

• US 20040172424A1
• Filed: 02/28/2003
• Published: 09/02/2004
• Est. Priority Date: 02/28/2003
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Saliba, Hani, Liu, Hai, Antonoff, Lauren, Rayson, Steven James, Edelstein, Noah
• Granted Patent: US 8,010,491 B2
• Time in Patent Office: Days
• US Class Current: 707/201
• CPC Class Codes: G06F 16/10 File systems; File servers

Abstract

A server is implemented with a modified file open action, which, when a user performs the modified open, initially opens a file without locking the file. When a user indicates (either explicitly or implicitly) that the user is attempting to or intending to open the file, the file can then be locked for editing. In this way, the default action when a user requests a file is to open the file without denying other users access to the file. Then, when the user indicates that editing should occur, the lock for the file is obtained.

Claims

1. A method for file replication on a first computer of a master file on a second computer, comprising:

storing a local copy on said first computer of said master file;

storing a shadow copy on said first computer of said master file;

permitting access to said local copy for modification; and

updating said shadow copy when said master file changes.

2. The method of claim 1, where said method further comprises:

storing a versioning state associated with said replication,

and where said step of permitting access to said local copy for modification comprises;

changing said versioning state when said local copy is modified.

3. The method of claim 2, where said step of changing said versioning state when said local copy is modified comprises:

setting said versioning state to a modified state indicating that said local copy has been modified.

4. The method of claim 1, where said method further comprises:

storing a versioning state associated with said replication;

and where said step of updating said shadow copy when said master file changes comprises;

changing said versioning state when said updating occurs.

5. The method of claim 1, where said step of updating said shadow copy when said master file changes comprises:

detecting that said local copy has been modified; and

resolving conflicts between said local copy and said updated shadow copy.

6. The method of claim 5, where said method further comprises:

storing a versioning state associated with said replication;

and where said step of resolving conflicts between said local copy and said updated shadow copy comprises;

changing said versioning state to a conflicted state indicating that a conflict exits.

7. The method of claim 5, where said step of resolving conflicts between said local copy and said updated shadow copy comprises:

presenting a conflict interface;

accepting a conflict resolution command; and

implementing said conflict resolution command.

8. The method of claim 7, where said implementation of conflict resolution commands comprises:

determining if a change should be made to said master file; and

communicating said change to be made to said second computer.

9. The method of claim 8, where said step of communicating said change to be made to said second computer comprises:

generating difference information regarding differences between said local copy and said master file; and

communicating said difference information to said master file.

10. The method of claim 1, where said step of updating said shadow copy when said master file changes comprises:

storing said local copy as a rollback copy; and

updating said local copy with said shadow copy.

11. The method of claim 10, where said step of storing said local copy as a rollback copy comprises:

presenting a rollback interface;

accepting a rollback command; and

displaying said rollback copy in response to said rollback command.

12. The method of claim 10, where said method further comprises:

storing a versioning state associated with said replication;

and where said step of storing said local copy as a rollback copy comprises;

changing said versioning state to a rollback available state.

13. The method of claim 10, further comprising:

tracking whether the local copy has been accessed;

and where said step of storing said local copy as a rollback copy comprises;

storing sail local copy as a rollback copy only if said local copy has been accessed.

14. At least one of an operating system, a computer readable medium having stored thereon a plurality of computer-executable instructions, a co-processing device, a computing device, and a modulated data signal carrying computer executable instructions for performing the method of claim 1.

15. A computer system for replication of a master file, said master file located on a second computer, said computer system at least intermittently operably connected to said second computer comprising:

local copy storage for storing a local copy on said first computer of said master file;

shadow copy storage storing a shadow copy on said first computer of said master file;

local copy modification module for permitting access to said local copy for modification; and

shadow copy updating module updating said shadow copy storage when said master file changes.

16. The computer system of claim 15, further comprising:

versioning state storage for storing a versioning state associated with said replication,

and where said local copy modification module changes said versioning state when said local copy is modified.

17. The computer system of claim 16, where said where said local copy modification module changes sets said versioning state to a modified state indicating that said local copy has been modified.

18. The computer system of claim 15, where said system further comprises:

versioning state storage for storing, a versioning state associated with said replication;

and where said shadow copy updating module changing said versioning state when said updating occurs.

19. The computer system of claim 15, where shadow copy updating module comprises:

local copy modification detection module for detecting that said local copy has been modified; and

conflict resolution module for resolving conflicts between said local copy and said updated shadow copy.

20. The computer system of claim 19, where said method further comprises:

versioning state storage for storing a versioning state associated with said replication;

and said conflict resolution module changes said versioning state to a conflicted state indicating that a conflict exits.

21. The computer system of claim 19, where said conflict resolution module comprises:

conflict interface module for presenting a conflict interface;

conflict resolution input module for accepting a conflict resolution command; and

conflict resolution implementation for implementing said conflict resolution command.

22. The computer system of claim 21, where said conflict resolution implementation comprises:

change determination module for determining if a change should be made to said master file; and

second computer change communication module for communicating said change to be made to said second computer.

23. The computer system of claim 15, where said second computer change communication module comprises:

difference generation module for generating difference information regarding differences between said local copy and said master file; and

second computer communication module for communicating said difference information to said master file.

24. The computer system of claim 15, where said shadow copy updating module comprises:

rollback storage for storing said local copy as a rollback copy; and

local copy update module for updating said local copy with said shadow copy.

25. The computer system of claim 24, where said local copy update module comprises:

a rollback interface presentation module presenting a rollback interface;

rollback command acceptance module accepting a rollback command; and

rollback copy display for displaying said rollback copy in response to said rollback command.

26. The computer system of claim 24, where said system further comprises:

versioning state storage for storing a versioning state associated with said replication,;

and where said rollback storage changes said versioning state to a rollback available state.

27. The computer system of claim 24, said system further comprising:

local copy access tracking module for tracking whether the local copy has been accessed;

and where said rollback storage for storing said local copy as a rollback copy comprises;

local copy access logic for storing said local copy as a rollback copy only if said local copy has been accessed.