Migration in a distributed file system
A method includes creating a temporary target s-stub file. The temporary target s-stub file points to a source share. The method further includes creating a plurality of stub files in a target top-level directory on a target share. Each stub file out of the plurality of stub files corresponds to source data. The source data includes files and subdirectories in a source top-level directory on a source share. The plurality of stub files include source information, the source information is associated with the temporary target s-stub file, and a source s-stub file points to the source share. The method further includes remapping the source s-stub to point to the target share.
1. A method comprising:
a) creating a temporary target s-stub file, the temporary target s-stub file pointing to a source share;
b) creating a plurality of stub files in a target top-level directory on a target share, each stub file out of the plurality of stub files corresponding to source data, the source data comprising files and subdirectories in a source top-level directory on a source share, the plurality of stub files comprising source information, the source information associated with the temporary target s-stub file, a source s-stub file pointing to the source share; and
c) remapping the source s-stub to point to the target share.
2. The method of claim 1 , further comprising d) for each stub file, out of the plurality of stub files, corresponding to a file in the source top-level directory, copying the file in the source top-level directory into the target top-level directory, overwriting the stub file, thus creating target data.
3. The method of claim 2 , further comprising e) for each stub file, out of the plurality of stub files, corresponding to a subdirectory in the source top-level directory, repeating b) and d) using a hidden directory on the target share as the target top-level directory and using the subdirectory as the source top-level directory, thus creating the target data in the hidden directory, deleting the stub file, and moving the target data out of the hidden directory and into the target top-level directory.
4. The method of claim 1 , further comprising deleting the temporary target s-stub file.
5. The method of claim 1 , further comprising:
freezing operations on the source top-level directory;
invalidating cached information about files copied from the source top-level directory; and
allowing operations to resume.
6. The method of claim 5 , further comprising:
verifying each file and subdirectory in the source top-level directory corresponds to a stub file out of the plurality of stub files in the target top-level directory;
allowing operations to resume if verification fails, and
continuing to create the target top-level directory and verify until verification does not fail.
7. The method of claim 1 , further comprising performing d) for source data that is the target of an access before the access occurs.
8. The method of claim 1 , further comprising applying, to the target data, updates to the source data such that the target data becomes identical to the source data.
9. The method of claim 1 , wherein creating the temporary target s-stub file comprises creating the temporary target s-stub file, the temporary target s-stub file pointing to a source share, the temporary target s-stub file unable to be remapped.
10. The method of claim 1 , further comprising deleting the source top-level directory.
11. The method of claim 1 , wherein the source share and the target share reside on different file servers.
12. The method of claim 1 , further comprising determining the source data based on a life-cycle migration policy.
13. A computer-readable medium storing a software program that, when executed by a processor, causes the processor to:
a) create a temporary target s-stub file, the temporary target s-stub file pointing to a source share;
b) create a plurality of stub files in a target top-level directory on a target share, each stub file out of the plurality of stub files corresponding to source data, the source data comprising files and subdirectories in a source top-level directory on a source share, the plurality of stub files comprising source information, the source information associated with the temporary target s-stub file, a source s-stub file pointing to the source share; and
c) remap the source s-stub to point to the target share.
14. The computer-readable medium of claim 13 , further causing the processor to d) for each stub file, out of the plurality of stub files, corresponding to a file in the source top-level directory, copy the file in the source top-level directory into the target top-level directory, overwriting the stub file, thus creating target data.
15. The computer-readable medium of claim 14 , further causing the processor to e) for each stub file, out of the plurality of stub files, corresponding to a subdirectory in the source top-level directory, repeat b) and d) using a hidden directory on the target share as the target top-level directory and using the subdirectory as the source top-level directory, thus creating the target data in the hidden directory, deleting the stub file, and moving the target data out of the hidden directory and into the target top-level directory.
16. The computer-readable medium of claim 13 , further causing the processor to delete the temporary target s-stub file.
17. The computer-readable medium of claim 13 , further causing the processor to:
freeze operations on the source top-level directory;
invalidate cached information about files copied from the source top-level directory; and
allow operations to resume.
18. The computer-readable medium of claim 17 , further causing the processor to:
verify each file and subdirectory in the source top-level directory corresponds to a stub file out of the plurality of stub files in the target top-level directory;
allow operations to resume if verification fails, and
continue to create the target top-level directory and verify until verification does not fail.
19. The computer-readable medium of claim 13 , further causing the processor to perform d) for source data that is the target of an access before the access occurs.
20. The computer-readable medium of claim 13 , further causing the processor to apply, to the target data, updates to the source data such that the target data becomes identical to the source data.
21. The computer-readable medium of claim 13 , wherein creating the temporary target s-stub file causes the processor to create the temporary target s-stub file, the temporary target s-stub file pointing to a source share, the temporary target s-stub file unable to be remapped.
22. The computer-readable medium of claim 13 , further causing the processor to delete the source top-level directory.
23. The computer-readable medium of claim 13 , wherein the source share and the target share reside on different file servers.
24. The computer-readable medium of claim 13 , further causing the processor to determine the source data based on a life-cycle migration policy.