Abstract: Described is a mechanism comprising a data screening filter and user mode service that applies (enforces) policies regarding allowing or blocking file content of a directory, based on matching the filename against patterns associated with that directory. An administrator configures a screening policy, such as the types of files to allow in a particular directory and the types of files to block. File groups of member patterns and non-member exclusion patterns are defined and selectively collected in directory screening objects (DSOs). A directory screening object (DSO) is associated with a directory. When an I/O create request specifying a filename and a target directory is received, the filename is evaluated against the member/non-member patterns in the file groups referenced by the DSO for that directory to make for an allow or block policy decision. If not matched, DSOs on parent directories are evaluated upwards seeking a policy decision.

Abstract: Described is a mechanism comprising a data screening filter and user mode service that applies (enforces) policies regarding allowing or blocking file content of a directory, based on matching the filename against patterns associated with that directory. An administrator configures a screening policy, such as the types of files to allow in a particular directory and the types of files to block. File groups of member patterns and non-member exclusion patterns are defined and selectively collected in directory screening objects (DSOs). A directory screening object (DSO) is associated with a directory. When an I/O create request specifying a filename and a target directory is received, the filename is evaluated against the member/non-member patterns in the file groups referenced by the DSO for that directory to make for an allow or block policy decision. If not matched, DSOs on parent directories are evaluated upwards seeking a policy decision.

Abstract: Described is a method and system by which reports of storage usage in computer systems are generated in an efficient manner by consolidating multiple requests for reports into a minimal number of volume scans, including by intelligently selecting a scanning method (e.g., of file system metadata versus find-first/find-next) and by performing parallel scans on different volumes. Namespace consolidation scans namespaces together, so as to generate multiple reports from the same set of files, reducing the number of volumes scans required to collect the data. Each volume scan may be a find-first, find next directory-based scan, or a volume metadata database scan. Time consolidation groups independent storage report generations together, such as storage report requests received within an administrator-specified interval. Parallel scans of different volumes may be performed, subject to I/O and processing resource limitations, and so that volumes partitioned on the same spindle are not scanned in parallel.

Abstract: Described is a method and system by which storage reports are generated from a volume snapshot set, rather than from a live volume. A volume snapshot set includes a representation or copy of a volume at a single point in time. By scanning the snapshot, a consistent file system image is obtained. Scanning may take place by enumerating a volume's directories of files, or, when available, by accessing a file system metadata of file information (e.g., a master file table) separately maintained on the volume. With some (e.g., hardware-based) snapshot technologies, the snapshot can be transported to another computing system for scanning by that other computing system, thereby avoiding burdening a live system's resources when scanning. Accurate and consistent storage reports are thus obtained at a single point in time, independent of the number of volumes being scanned.

Abstract: A method and system for backing up and restoring data of production servers. A mapping that maps volumes of production servers to volumes of a data protection server is maintained on the data protection server. When volumes of the data protection server are backed up, the mapping may be stored on the archive media together with the data of the volumes. Later, during a restore, the mapping is read from the archive media. The mapping allows the data to be restored to the data protection server or directly to the production servers.

Abstract: Described is a storage reports scanner that works to generate reports of storage usage in computer systems in an efficient manner. The scanner receives a set of namespaces for a file system volume from a storage reports engine. The scanner scans file system metadata to construct a directory table of entries corresponding to a directory tree of nodes representative of the hierarchy of directories of the file system volume. Each node corresponding to a namespace in the namespace set is marked as included. A second scan of the file system metadata determines, for each file, whether that file is in or under an included directory by accessing the directory table. For each file that is in or is under an included directory, file information is returned to the engine. The engine may request the scanner to provide full path information, which the scanner determines via the directory table.

Abstract: Described is a storage reports duplicate file detector that operates by receiving file records during a first scan of file system metadata. The detector computes a hash based on attributes in the record, and maintains the hash value in association with information that indicates whether a hash value corresponds to more than one file. In one implementation, the information corresponds to the amount of space wasted by duplication. The information is used to determine which hash values correspond to groups of potentially duplicate files, and eliminate non-duplicates. A second scan locates file information for each of the potentially duplicate files, and the file information is then used to determine which groups of potentially duplicate files are actually duplicate files.

Abstract: A framework for taking shadow copies and performing backups in systems that may have data spread across multiple machines. A requester communicates names to a primary coordinator and requests the creation of shadow copies of all the volumes associated with the names. The primary coordinator communicates with one or more writers and one or more secondary coordinators to create the shadow copies of the volumes. The primary and one or more secondary coordinators create shadow copies of one or more of the volumes that reside on the machines upon which they execute. After the shadow copies of the volumes have been created, the requester may obtain data from the shadow copies and create a consistent backup.

Abstract: A technique for recalling data objects stored on media. A queue is created for each medium on which data objects are located, where each request to recall a data object is placed on the queue corresponding to the medium on which the data object is located. A queue is “active” when its corresponding medium is mounted and being used for recall; otherwise the queue is “non-active.” A thread is created for each active queue, where the thread retrieves from a medium the requested items on the active queue. When plural drives are available for mounting and reading media, plural queues may be active concurrently, so that the plural queues' respective threads may recall items from the plural media in parallel. Preferably, the requests on each queue are organized in an order such that the offset locations of the requested items form two monotonically increasing sequences.

Abstract: A method for concurrent data migration includes classifying files to be migrated into plural jobs, selecting media to which to migrate each job, and using plural drives concurrently to write the jobs to the media. The selection of a medium is performed in a way that prevents the number of writeable media from exceeding the number of available drives, unless no allocated medium has sufficient space to store any files in a migration job. A medium is preferentially selected that has already been allocated for writing, has space to store at least one file in the job, is not in use for another job, and can be robotically mounted on a drive. If such a medium does not exist, then the set of available media is canvassed to locate an alternative medium.

Abstract: A host server hosting one or more virtual machines can back up host volumes and the one or more virtual machines installed thereon in an application-consistent manner. In one implementation, a host-level requestor instructs a host-level writer to identify which virtual machines qualify for application-consistent backups. The host-level requestor then instructs the host-level writer to initiate virtual machine backups through guest-level requesters in each appropriately-configured virtual machine, wherein the virtual machines create application-consistent backups within the virtual machine volumes. The host-level requester then initiates snapshots of the server volumes on the host-level. The virtual machine-level snapshots can thus be retrieved from within the host-level snapshots of the server volumes.

Abstract: A method for concurrent data migration includes classifying files to be migrated into plural jobs, selecting media to which to migrate each job, and using plural drives concurrently to write the jobs to the media. The selection of a medium is performed in a way that prevents the number of writeable media from exceeding the number of available drives, unless no allocated medium has sufficient space to store any files in a migration job. A medium is preferentially selected that has already been allocated for writing, has space to store at least one file in the job, is not in use for another job, and can be robotically mounted on a drive. If such a medium-does not exist, then the set of available media is canvassed to locate an alternative medium.

Abstract: Aspects of the subject matter described herein relate to transactions. In aspects, a consistency requester such as a shadow copy service requests to have a consistent view of a set of resources. In response, transactions that are in a problematic state are allowed to exit the problematic state while new and existing transactions that are not in the problematic state are allowed to perform any work except work that takes them into the problematic state. After no transactions are in the problematic state, a consistent view of the set of resources is available. This view may be used by the consistency requester as desired. Afterwards, the consistency requester may indicate that a consistent view is no longer needed. Transactions are then allowed to enter the problematic state. Transactions may also be allowed to enter the problematic state if a timeout elapses.

Abstract: Described is a storage reports scanner that works to generate reports of storage usage in computer systems in an efficient manner. The scanner receives a set of namespaces for a file system volume from a storage reports engine. The scanner scans file system metadata to construct a directory table of entries corresponding to a directory tree of nodes representative of the hierarchy of directories of the file system volume. Each node corresponding to a namespace in the namespace set is marked as included. A second scan of the file system metadata determines, for each file, whether that file is in or under an included directory by accessing the directory table. For each file that is in or is under an included directory, file information is returned to the engine. The engine may request the scanner to provide full path information, which the scanner determines via the directory table.

Abstract: Described is a storage reports duplicate file detector that operates by receiving file records during a first scan of file system metadata. The detector computes a hash based on attributes in the record, and maintains the hash value in association with information that indicates whether a hash value corresponds to more than one file. In one implementation, the information corresponds to the amount of space wasted by duplication. The information is used to determine which hash values correspond to groups of potentially duplicate files, and eliminate non-duplicates. A second scan locates file information for each of the potentially duplicate files, and the file information is then used to determine which groups of potentially duplicate files are actually duplicate files.

Abstract: Described is a method and system by which reports of storage usage in computer systems are generated in an efficient manner by consolidating multiple requests for reports into a minimal number of volume scans, including by intelligently selecting a scanning method (e.g., of file system metadata versus find-first/find-next) and by performing parallel scans on different volumes. Namespace consolidation scans namespaces together, so as to generate multiple reports from the same set of files, reducing the number of volumes scans required to collect the data. Each volume scan may be a find-first, find next directory-based scan, or a volume metadata database scan. Time consolidation groups independent storage report generations together, such as storage report requests received within an administrator-specified interval. Parallel scans of different volumes may be performed, subject to I/O and processing resource limitations, and so that volumes partitioned on the same spindle are not scanned in parallel.

Abstract: Described is a method and system by which storage reports are generated from a volume snapshot set rather than the live volume or volumes, wherein a volume snapshot set comprises a representation or copy of one or more volume at a single point-in-time. By scanning the snapshot, a consistent file system image is obtained. Scanning may take place by enumerating a volume's directories of files, or, when available, by accessing a file system metadata of file information (e.g., a master file table) separately maintained on the volume. With some (e.g., hardware-based) snapshot technologies, the snapshot can be transported to another computing system for scanning by that other computing system, thereby avoiding burdening a live system's resources when scanning. Accurate and consistent storage reports are thus obtained at a single point in time, independent of the number of volumes being scanned.

Abstract: A method and system for backing up and restoring data of production servers. A mapping that maps volumes of production servers to volumes of a data protection server is maintained on the data protection server. When volumes of the data protection server are backed up, the mapping may be stored on the archive media together with the data of the volumes. Later, during a restore, the mapping is read from the archive media. The mapping allows the data to be restored to the data protection server or directly to the production servers.

Abstract: Method and system for maintaining namespace consistency between selected objects maintained by a file system and a filter associated therewith. Metadata regarding selected objects of a file system is maintained by a filter while the filter is attached to the file system and persisted in non-volatile storage. The namespace of the file system may be changed while the filter is unattached from the file system. Afterwards, when the filter is attached to the file system, the namespace of the filter is synchronized with the namespace of the file system for the selected objects.

Abstract: Described is a mechanism comprising a data screening filter and user mode service that applies (enforces) policies regarding allowing or blocking file content of a directory, based on matching the filename against patterns associated with that directory. An administrator configures a screening policy, such as the types of files to allow in a particular directory and the types of files to block. File groups of member patterns and non-member exclusion patterns are defined and selectively collected in directory screening objects (DSOs). A directory screening object (DSO) is associated with a directory. When an I/O create request specifying a filename and a target directory is received, the filename is evaluated against the member/non-member patterns in the file groups referenced by the DSO for that directory to make for an allow or block policy decision. If not matched, DSOs on parent directories are evaluated upwards seeking a policy decision.