METHOD AND APPARATUS FOR SPLITTING A REPLICATED VOLUME

• US 20090119344A9
• Filed: 10/31/2006
• Published: 05/07/2009
• Est. Priority Date: 04/14/2003
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Novell Incorporated (Open Text Corporation)
• Inventors: Toner, Stephen G.
• Granted Patent: US 7,805,401 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/119 Details of migration of file systems migration mechanisms in storage systems G06F3/0647

Abstract

At least two replicated instances of a source volume are split while allowing clients to access data moved during the split. Clients are redirected to the first replicated instance of the source volume. The first replicated instance is split by first moving files in a split path from the first replicated instance to the target volume. Then, after the files in the split path have been successfully moved to the target volume, a junction is inserted at the split directory to redirect clients to the target volume. After the first replicated instance is split, a second junction replaces the split path on the replicated instance of the first replicated instance.

Claims

1. A system to move a subdirectory tree, comprising:

a computer;

a first replicated instance of a source volume;

a directory tree on the first replicated instance of the source volume, the directory tree including a split path, the split path including a split directory;

a second replicated instance of the source volume, the second replicated instance including a copy of the directory tree, the copy of the directory tree including a copy of the split path, the copy of the split path including a split directory;

a target volume;

a means for redirecting a client from the second replicated instance of the source volume to the first replicated instance of the source volume;

a file verifier to verify that each file in the copy of the split path on the second replicated instance of the source volume is closed; and

a subdirectory mover to move each file in the split path on the first replicated instance of the source volume to the target volume while allowing the client to access each file in the split path on the first replicated instance of the source volume.

2. A system according to claim 1, further comprising a volume manager including a junction creator to insert a junction at the split directory on the second replicated instance of the source volume pointing to a temporary distributed file system globally unique identifier (DFS GUID) assigned to the first replicated instance of the source volume.

3. A system according to claim 2, further comprising a DFS GUID creator to create the temporary DFS GUID assigned to the first replicated instance of the source volume.

4. A system according to claim 2, further comprising a junction remover to remove from the second replicated instance of the source volume the junction pointing to the temporary DFS GUID assigned to the first replicated instance of the source volume.

5. A system according to claim 1, further comprising a volume manager including a junction creator to insert a junction at the split directory on the first replicated instance of the source volume pointing to a DFS GUID assigned to the target volume.

6. A system according to claim 5, wherein the volume manager is operative to insert a second junction at the split directory on the second replicated instance of the source volume pointing to the second DFS GUID assigned to the target volume and to delete each file in the copy of the split path on the second replicated instance of the source volume.

7. A system according to claim 5, further comprising a replication manager to propagate a copy of the second junction to the second replicated instance of the source volume at the split directory on the second replicated instance of the source volume and to replicate a deletion of each file in the copy of the split path on the second replicated instance of the source volume.

8. A computer-implemented method to move a subdirectory tree on a first replicated instance of a source volume to a target volume, comprising:

assigning to the first replicated instance of the source volume a first distributed file system globally unique identifier (DFS GUID);

inserting at a second replicated instance of the source volume a first junction pointing to the first DFS GUID;

verifying each file in a split path on the second replicated instance of the source volume is closed, wherein the split path includes a split directory;

copying each file in a corresponding split path on the first replicated instance of the source volume to the target volume;

assigning to the target volume a second DFS GUIlD;

inserting at the split directory on the first replicated instance of the source volume a second junction pointing to the second DFS GUID;

deleting each file in the split path on the first replicated instance of the source volume;

removing from the second replicated instance of the source volume the first junction to the first DFS GUID assigned to the first replicated instance of the source volume; and

propagating in the second replicated instance of the source volume the move of the files in the split path from the first replicated instance of the source volume to the target volume.

9. A method according to claim 8, wherein propagating in the second replicated instance of the source volume the move of the files in the split path from the first replicated instance of the source volume to the target volume includes:

inserting at the split directory on the second replicated instance of the source volume a copy of the second junction to the second DFS GUID pointing to the target volume; and

deleting each file in the split path on the second replicated instance of the source volume.

10. A method according to claim 8, wherein:

assigning to the first replicated instance of the source volume a first DFS GUID includes storing an assignment of the first DFS GUID to the first replicated instance of the source volume in a volume locator database (VLDB); and

assigning to the target volume a second DFS GUID includes storing an assignment of the second DFS GUID to the target volume in the VLDB.

11. A method according to claim 8 further comprising un-assigning the first DFS GUID from the first replicated instance of the source volume.

12. A method according to claim 11, wherein un-assigning the first DFS GUID from the first replicated instance of the source volume includes removing an assignment of the first DFS GUID to the first replicated instance of the source volume in a volume location database (VLDB).

13. A computer apparatus to move a subdirectory tree from a replicated volume to a target volume, comprising:

a volume locator database (VLDB) to store a first entry including a first assignment of a first distributed file system globally unique identifier (DFS GUID) to a first replicated instance of a source volume, a second entry including a second assignment of the first DFS GUID to a second replicated instance of the source volume, and a third entry including a third assignment of a second DFS GUID to the target volume;

a DFS GUID creator to create a fourth entry in the VLDB including a fourth assignment of a temporary DFS GUID to the first replicated instance of the source volume; and

a volume manager including a junction creator to insert a first junction at the second replicated instance of the source volume pointing to the temporary DFS GUID assigned to the first replicated instance of the source volume.

14. An apparatus according to claim 13, further comprising a file verifier to verify that each file in a split path on the second replicated instance of the source volume is closed.

15. An apparatus according to claim 14, further comprising a subdirectory mover to move each file in the split path on the first replicated instance of the source volume to the target volume while allowing a client to access a file in the split path of the first replicated instance of the source volume.

16. An apparatus according to claim 15, wherein the volume manager is operative to insert at a split directory on the first replicated instance of the source volume a second junction pointing to the second DFS GUID assigned to the target volume.

17. An apparatus according to claim 16, further comprising a junction remover to remove the first junction from the second replicated instance of the source volume.

18. An apparatus according to claim 16, wherein the volume manager is operative to insert at the split path on the second replicated instance of the source volume a third junction pointing to the second DFS GUID assigned to the target volume and to delete each file in the split path on the second replicated instance of the source volume.

19. An apparatus according to claim 16, further comprising a replication manager to propagate the second junction to the second replicated instance of the source volume at the split path on the second replicated instance of the source volume and to replicate a deletion of each file in the split path on the second replicated instance of the second replicated instance of the source volume.

20. An article, comprising a storage medium, said storage medium having stored thereon instructions, that, when executed by a machine, result in:

assigning to a first replicated instance of a source volume a first distributed file system globally unique identifier (DFS GUID);

inserting at a split directory of a second replicated instance of the source volume a first junction pointing to the first DFS GUID;

verifying each file in a split path on the second replicated instance of the source volume is closed;

copying each file in the split path on the first replicated instance of the source volume to a target volume;

assigning to the target volume a second DFS GUID;

inserting at the split directory on the first replicated instance of the source volume a second junction pointing to the second DFS GUID;

deleting each file in the split path on the first replicated instance of the source volume;

removing from the second replicated instance of the source volume the first junction to the first DFS GUID assigned to the first replicated instance of the source volume; and

propagating in the second replicated instance of the source volume the move of the files in the split path from the first replicated instance of the source volume to the target volume.

21. An article according to claim 20, wherein propagating in the second replicated instance of the source volume the move of the files in the split path from the first replicated instance of the source volume to the target volume includes:

inserting at the split directory on the second replicated instance of the source volume a copy of the second junction to the second DFS GUID pointing to the target volume; and

deleting each file in the split directory on the second replicated instance of the source volume.

22. An article according to claim 20, wherein:

assigning to the first replicated instance of the source volume a first DFS GUID includes storing an assignment of the first DFS GUID to the first replicated instance of the source volume in a volume locator database (VLDB); and

assigning to the target volume a second DFS GUID includes storing an assignment of the second DFS GUID to the target volume in the VLDB.

23. An article according to claim 20 further comprising un-assigning the first DFS GUID from the first replicated instance of the source volume.

24. An article according to claim 23, wherein un-assigning the first DFS GUID from the first replicated instance of the source volume includes removing an assignment of the first DFS GUID to the first replicated instance of the source volume in a volume location database (VLDB).