International Business Machines Corporation

Richard Alan Schaeffer

Kaukab Uddin

William Frank Micka

Brent Cameron Beardsley

Michael Koester

Minh-Ngoc Le Huynh

Kevin L Miner

Satish Chandra Penmetsa

Olympia Gluck

James Chien-Chiung Chen

James C Chen

William Henry Travis

David Brent Schreiber

Lourdes Magally Gee

Gabriel G Walder

Thao Bich Bui

Raymond Eugene Garcia

Frederick J Carberry

Rufus J Twito

Provided are a computer program product, system, and method for deleted data restoration in accordance with one embodiment of the present description, in which in response to a search request having specified search parameters, data of a deleted data unit is located as a function of specified search parameters. In addition, metadata erased as a result of the deletion operation, is restored as a function of the located data. Accordingly, the previously deleted data unit is undeleted and access to the previously deleted data unit is restored via the restored metadata. Other aspects of deleted data restoration in accordance with the present description are described.

Deleted data restoration

In one aspect of storage device status management in accordance with the present description, a host can determine not only whether a particular volume maintained by a storage unit controlled by a storage controller is on-line with respect to another host, but also whether that volume is actually in use by another host. Accordingly, should one host determine that a volume is in use by another host, the one host can defer its use of the volume until the volume is no longer in use by another host. In this manner, conflicts which may lead to loss of data integrity may be reduced or eliminated, providing a significant improvement in computer technology. Other features and aspects may be realized, depending upon the particular application.

Storage device status management for conflict avoidance in a data storage system

An apparatus, system, and method are provided for controlling link status changes across multiple independent control modules. The apparatus includes a copy services module configured to control multiple link adapters, each configured to establish multiple communication links between a source and a target storage device. The adapter transmits a link status change notification to the copy services module and starts a timer upon transmitting the link status change notification. The copy services module simultaneously processes link status change notifications from a plurality of communication links. The system includes a communications network and a plurality of storage devices having the above described apparatus. The method includes controlling a plurality of link adapters configured to establish multiple communication links between storage devices, transmitting a link status change notification, starting a timer upon transmitting the link status change notification, and simultaneously processing link status change notifications from a plurality of communication links.

Apparatus, system, and method for controlling link status changes

A method, apparatus and program storage device for providing asynchronous status messaging in a data storage system Asynchronous events are returned from a target to an initiator in response to a Read Message from the initiator. The return status message may or may not be associated with a previously given command or Logical Unit (LUN).

Method, apparatus and program storage device for providing asynchronous status messaging in a data storage system

A method of error management in a data storage system having a target device, with the target device receiving commands from a first initiator and the target device concurrently receiving commands from a second initiator. The target device is typically a storage device operating as a PPRC secondary. A first initiator is a device which communicates with the target device through small computer systems interface (SCSI) protocol. The first initiator is typically a host computer or server. The second initiator communicates with the target device through peer-to-peer remote copy PPRC initiator mode commands. The second initiator is typically a separate storage device in a peer-to-peer remote copy (PPRC) relationship with the target device. The method consists of managing errors associated with a command sent to the target device from the first initiator independently from the management of errors associated with a command sent to the target device from the second initiator.

Concurrent PPRC/FCP and host access to secondary PPRC/FCP device through independent error management

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Antioch, CA, United States of America

Richard Alan Schaeffer