Data storage management for network interconnected processors using transferrable placeholders

摘要

The data storage management system provides the capability to move and/or copy the placeholder files from one file server volume to another file server volume, even if the destination file server volume resides on a different file server. This is accomplished by the use of unique and immutable migration keys which are included in the placeholder entries to identify the location of the associated data file with absolute certainty. In addition, a duplicate copy of the placeholder catalog file is maintained in the system to prevent loss of file system integrity in the event that the active placeholder catalog file is corrupted. This placeholder data is maintained in a placeholder volume catalog which provides users with a file-system-like view of the placeholder files which reside on the selected volume.