Method for database assisted file system restore

A method of rebuilding a subdirectory structure in a filesystem comprising the following steps:

• a. creating a database table;
• b. recording an entry in said table for each directory/subdirectory created in said filesystem;
• c. updating an entry corresponding to a directory/subdirectory when said directory/subdirectory is modified;
• d. identifying a target subdirectory to be rebuilt;
• e. finding an entry in said database table associated with said desired subdirectory and extracting a directory/subdirectory name from said entry;
• f. identifying a parent directory of said entry found in said previously executed step (i.e step e or g);
• g. finding an entry in said database table associated with said parent directory and extracting a directory/subdirectory name from said entry;
• h. recursively applying steps f and g until a parent directory is not identified in step f, and
• i. rebuilding a full directory path by concatenating all said extracted directory/subdirectory names using a last-found first-out order.

A method of restoring database managed external files to a restored filesystem's directory structure comprising the steps:

• a. identifying a desired previous database state;
• b. restoring a filesystem's directory structure to a state substantially similar to said filesystem's directory structure at said previous database state;
• c. identifying every one of said external files managed by said database;
• d. extracting at least one version of each of said identified external files and a corresponding database state identifier from an archival storage facility;
• e. if only one version of said external file is extracted, then selecting said version;
• f. if more than one version of said external file is extracted, then selecting said version which matches said desired previous database state;
• g. repeating steps d through f for each of said external files identified in step c, and
• h. restorin said selected versions of each of said identified external files to said filesystem's directory structure.

A method of using a database management system to maintain a record of directory operations on a filesystem which comprises the following steps:

• a. creating a managed database table;
• b. recording an entry in said table for each directory/subdirectory created in said filesystem, said entry comprising:
• a directory/subdirectory identifier;
• a status flag;
• a creation time-stamp identifier, and
• a modification time-stamp identifier;
• c. updating an entry corresponding to a directory/subdirectory when said directory/subdirectory is modified.

An article of manufacture comprising a computer medium having computer readable program code embodied therein which implements a restoring a filesystem's directory structure to a point in time comprising:

• a. creating a database table;
• b. recording an entry in said table for each directory/subdirectory created in said filesystem, wherein each of said table entries comprises:
• a directory/subdirectory name,
• a filesystem identifier,
• a node identifier within said filesystem, and
• a parent directory's node identifier;
• c. updating an entry corresponding to a directory/subdirectory when said directory/subdirectory is modified;
• d. reconstructing said filesystem by applying at least one of said entries to restore said filesystem's directory structure to a previous state.

A system for restoring a filesystem's directory structure to a point in time comprising:

• a filesystem comprising one or more directories;
• a database management system;
• a database table, managed by said database management system, comprising an entry associated with each of said directories in said filesystem;
• a database agent which updates said entry when said associated directory is modified;
• a restoration process which re-creates a directory in said filesystem according to said associated database table entry, and
• wherein at least one of said directories is re-created in order to restore said filesystem's directory structure to a previous state.