Patent ID: 7165079

Claim:
A computer implemented method for restoring a single data stream file to an active file system from a snapshot of a file system executing on a file server, the method comprising the steps of: determining whether the single data stream file is (a) absent from the active file system, (b) exists in the active file system and is a large file or (c) exists in the active file system and is a small file a type of file; if the single data stream file is absent from the active file system, performing an empty file routine; if single data stream file exists in the active file system and is a large file, performing a restore routine, the restore routine comprising the steps of: (a) creating a twin inode, the twin inode including a copy of block pointers associated with the file in the active file system; (b) creating a new inode associated with the file to be restored; (c) performing a reconciliation of the block pointers included in the twin inode with a set of block pointers included in the snapshot; (d) copying a set of streams associated with the file from the snapshot to the active file system; and if the single data stream file exists in the active file system and is a small file, performing a conventional restore operation.