Emc Corporation

Bruce Alan Pocock

Douglas Eric LeCrone

Hana Moreshet

Natan Vishlitzky

Haim Kopylovitz

Paul A Linstead

Ishay Kedem

Denis J Burt

Jeffrey L Jones

Roger A Ouellette

Isbay Kedem

A system for injecting I/O faults into a closed system, for example, the injection of link level I/O faults, involves the use of a simulated computing environment. In an embodiment, the system provides for fault injection using an emulated IBM System z environment and including the use of FICON and/or other suitable communication channel protocols. The emulated System z environment may include a simulated z/OS and/or emulated System z hardware and software components.

I/O fault injection using simulated computing environments

A reclaim system provides for marking each track that is intended to be reclaimed in one or more storage devices and detecting and reclaiming such tracks. The reclaim system may include a feature and/or utility that may be used to mark, detect and return tracks to a free track pool of a virtual provisioning storage system in connection with the use of one or more thin Count Key Data (CKD) devices. Reclaim processing may include identifying tracks to be reclaimed, marking mark the tracks to be reclaimed, detecting tracks that have been marked to be reclaimed, and performing a reclaim task to return the marked and detected tracks to the free track pool, thereby reclaiming the tracks.

Space reclamation with virtually provisioned devices

A host computer system (host) includes an application that generates I/O commands for a first type of point-in-time (PIT) copy operation, and an I/O subsystem coupled to a data storage system capable of performing a second type of PIT copy operation. The host processes the I/O commands as part of an emulation of the first type of PIT copy operation, including determining whether the I/O commands require modification for the emulation, and if so whether they are of a back-end type or an out-of-band type. The I/O commands that do not require modification are processed without modification via the I/O subsystem. For the back-end I/O commands, (i) an intercept condition is set, (ii) the I/O commands are processed via the I/O subsystem, and (iii) upon completion with the intercept condition set, the results are modified so as to indicate to the application that the first type of PIT copy operation can be performed on the storage volumes. For the out-of-band I/O commands, (i) corresponding commands of the second type of PIT copy operation are processed via the I/O subsystem in lieu of the out-of-band I/O commands, and (ii) upon completion of the substituted I/O commands, corresponding results are returned to the application as though the out-of-band I/O commands had been processed by the I/O subsystem. Using this technique, a host that initiates only PIT copying operations of the first type can be used with storage systems that support second-type PIT copying operations.

Emulation of point-in-time data copying operations

Handling data includes providing a first storage area of a first type that contains sections of data, providing a second storage area of the first type that contains sections of data, providing a third storage area of a second type where the second type has, for each section thereof, a pointer to one of: a corresponding section of data of the first storage area and a corresponding section of data of the second storage area, causing the third storage area to be not available for accessing, and after causing the third storage area to not be available for accessing, providing data from the second storage area corresponding to pointers of the third storage area that point to sections of the second storage area.

Deactivating virtual devices and rolling backup

A mass storage business continuance time maker function host system that allows one or more MVS mainframe hosts to have the time to: establish business continuation volumes to mirror the standard mass storage volumes; synchronize business continuation volumes with the standard volumes so that their contents are identical; split off a business continuation volume from its standard volume counterpart to make the business continuation volume available for other purposes; and enable a business continuation volume to be used to restore the contents of a standard volume&#x2014;all without halting or disrupting the business applications using standard volumes. These and related services are provided in a transparent manner to a host mainframe by manipulating MVS format volume labels, volume tables of contents and indexes, catalog entries, data set names and similar mechanisms on mass storage devices connected to host mainframes using the MVS operating system.

Host system for mass storage business continuance volumes

Restoring data includes providing data in a first storage area that contains sections of data, providing data in a second storage area where the second type has, for each section of data thereof, at least one of: a pointer to a corresponding section of data of the first storage area and a pointer to corresponding section of data of a third storage area of the first type. In one embodiment, a sections of the first storage area are replaced with pointers to the third storage area. In other embodiments, sections of a fourth storage area of the first type are replaced with pointers to the third storage area and optionally with pointers to the first storage area. In another embodiment, data is copied from the second storage area to a third storage area of the second type.

Restoring virtual devices

Accessing data includes a host establishing a relationship between a first storage area of a first type containing data and a second storage area of a second type containing pointers to data provided in storage areas of the first type, where the storage areas are provided in a storage device coupled to the host. In response to the host writing data to a particular section of the first storage area after establishing the relationship, the particular section is copied from the first storage area to a third storage area of the first type prior to the write operation being executed. A corresponding pointer of the second storage area is adjusted to point to the third storage area.

Virtual storage devices

A method for copying data from a source disk storage device to a destination disk storage device. In response to a copy command from a requesting host application identifying the storage locations in source and destination disk storage devices, an environment is established. Thereafter a calling system receives an immediate response that the copy operation is complete even though no data has been copied. Application programs may access storage locations in either the source or the destination disk storage device during the copy phase. A copy program transfers the date on a track-by-track basis to the storage locations in the destination disk storage device. Procedures assure that any data access to a particular track in either the source or destination disk storage devices by any application prior to the transfer of that track are accommodated to maintain data integrity.

Method and apparatus for making independent data copies in a data processing system

Data is copied from a source storage device to a destination storage device in a differential mode. An extents track defines all tracks to be transferred during a first copying operation. Complementary track tables for source and destination storage devices establishing the totality of changes in data since a previous copying program to limit subsequent copying to data on changed tracks only.

Method and apparatus for making differential independent data copies in a data processing system

A method for copying a data file from a source device to a destination device. In response to a copy command from a requesting host application identifying the source file and the storage locations in a destination, an extents track is formed to establish an environment in which the file will be copied. The calling system receives an immediate response that the copy operation is complete even though no data has been copied. Application programs may access the file in either the source or the destination. A copy program transfers the file on a track-by-track basis to the destination storage locations. Procedures assure that any data access to a particular track in either the source or destination by any application prior to the transfer of that track are accommodated to maintain data integrity.

A mass storage business continuance time maker function host system that allows one or more MVS mainframe hosts to have the time to: establish business continuation volumes to mirror the standard mass storage volumes; synchronize business continuation volumes with the standard volumes so that their contents are identical; split off a business continuation volume from its standard volume counterpart to make the business continuation volume available for other purposes; and enable a business continuation volume to be used to restore the contents of a standard volume&mdash;all without halting or disrupting the business applications using standard volumes. These and related services are provided in a transparent manner to a host mainframe by manipulating MVS format volume labels, volume tables of contents and indexes, catalog entries, data set names and similar mechanisms on mass storage devices connected to host mainframes using the MVS operating system.

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Titusville, FL, United States of America

Bruce Alan Pocock