Abstract: Generating a consistent point in time copy of data in a source volume and a target volume is achieved responsively to a first data modification request by writing a first altered version of the data onto a single source volume, asynchronously transferring the first altered version from the first storage site to a target volume located at a remote second storage site, while avoiding copying the first altered version onto other volumes at the first storage site. While asynchronously transferring the first altered version de-queuing a second modification request, and responsively to the second modification request synchronously transferring the first altered version from the first storage site to the target volume. Then a second altered version of the data is written to the single source volume and a copy transferred to the target volume in like manner.

Abstract: Methods, apparatus and systems for data storage including initiating a destaging process in a storage system for destaging data from a cache to a mass storage device. Upon inputting a standby command to the storage system to inhibit the destaging of the data in a specified range, the destaging of the data in the specified range from the cache to the mass storage device is inhibited.

Abstract: A method for managing operations in a data storage system comprising at least a first storage controller operating according to a plurality of operation states set by a managing entity is provided. The method comprises the first storage controller performing a first operation associated with a first operation state, in response to the managing entity updating state information stored in a data structure readable by the first storage controller.

Abstract: A method for storing an information block that includes determining to store a current version of an information block stored in a memory unit. The checking if a current version of the information is already stored in a storage unit. The current version of the information block is sent from the memory unit to the storage unit if the answer is negative. Generating storage unit location information indicative of a location, at the storage unit, of the current version of the information block if the answer is positive.

Abstract: A method for tracking transactions performed on a non-volatile storage medium. The medium consists of a plurality of storage ranges. The method includes assigning respective local counters to the plurality of storage ranges, the local counters having respective local counter values, and storing the local counter values together in a selected region of the non-volatile storage medium. The method further includes updating the respective local counter values stored in the selected region responsively to the transactions performed on the storage ranges to which the local counters are respectively assigned. The method also includes reading and combining the local counter values from the selected region in order to determine a global counter value with respect to the non-volatile storage medium.

Abstract: A method for generating a consistent point in time copy of data, the method includes: selecting at least one selected data block to be copied from a source volume to a target volume in response to a request to generate a consistent point in time copy of multiple data blocks; waiting until the source volume is ready to send the at least one selected data block to a remote volume while queuing at least one data block modify request; de-queuing the at least one queued modify requests while copying the at least one selected data block from the source volume to the target volume; wherein the copying includes utilizing a first copying mechanism to copy a first selected data block if a request to modify the first selected block is de-queued before the first selected data block is copied to the target volume; else, the copying includes using a second copying mechanism that is slower than the first copying mechanism.

Abstract: Methods, apparatus and systems for data storage including initiating a destaging process in a storage system for destaging data from a cache to a mass storage device. Upon inputting a standby command to the storage system to inhibit the destaging of the data in a specified range, the destaging of the data in the specified range from the cache to the mass storage device is inhibited.

Abstract: A method and system for authentication are provided for verifying a service provider and providing a secure session. The method carried out at the service provider (402) includes: starting (403) a session with a client (401); receiving a challenge (405) from the client (401); responding to the challenge with a response (408); and sending a key (408) to the client (401) in non-OCR format, wherein the key is used for the session between the client (401) and the service provider (402). The response to the challenge is known only to the client (401) and the service provider (402). The key is used by the client (401) to encrypt (412) all the communications with the service provider (402) in the session. The response and the key may be sent to an alternative channel previously supplied by the client (401).

Abstract: A method and computer readable product for managing data, the method includes: providing a first data structure representative of insert or update operations to entries identified by keys and providing a second data structure representative of branch creation operations wherein the second data structure stores branch identifiers and branch timing information; receiving a request to lookup a version of data at a read timestamp; scanning the first and the second data structures to locate that version of data; and receiving a request to create a branch that starts by a version of data at a requested timestamp and updating the second data structure accordingly.

Abstract: A method for accessing a storage device, the method includes: receiving, by storage device, a block based storage access command and cryptographically secured access control information; wherein the block based storage access command and the cryptographically secured access control information are associated with at least one fixed size block of data and with a client; processing at least a portion of the cryptographically secured access control information by using a secret key accessible to the storage device and to a security entity; and selectively executing the block based storage access command in response to a result of the processing.

Abstract: Provided are a method, system, and article of manufacture for copying storage. Data sent from a first storage unit is synchronously copied at a second storage unit. The copied data is sent asynchronously from the second storage unit to a third storage unit.

Abstract: A method, system and computer program product for storing transient state information, the method includes: defining a first logical storage space within at least one storage device in response to at least one characteristic of a processing system logical memory space utilized for storing current transient state information of the processing system; repetitively storing current transient state information at a logical location within the first logical storage space that corresponds to a logical location of the current transient state information within the processing system logical memory space and storing, within a second logical storage space, previous transient state information.

Abstract: Methods, apparatus and systems for data storage including initiating a destaging process in a storage system for destaging data from a cache to a mass storage device. Upon inputting a standby command to the storage system to inhibit the destaging of the data in a specified range, the destaging of the data in the specified range from the cache to the mass storage device is inhibited.

Abstract: A method for storing multiple types of information, the method includes: storing information representative of a content of a persistent memory entity at a certain point in time; and storing information representative of a state of a virtual machine at the certain point in time. A computer program product including a computer usable medium including a computer readable program, wherein the computer readable program when executed on a computer causes the computer to: store information representative of a content of a persistent memory entity at a certain point in time; and store information representative of a state of a virtual machine at the certain point in time.

Abstract: Method, device and computer program product for support of maintaining a system. The method includes: evaluating a current system state and detecting a first lattice element corresponding to the current system state; locating at least one state improvement path, within a lattice that represents states of the system, between the first lattice element and a second lattice element representative of a target system state; determining, for at least one state improvement path, rules that should be satisfied in order to reach the system target state; and determining how to fulfill the rules associated with at least one state improvement path.

Abstract: Provided are a method, system, and article of manufacture wherein a command is received for writing data to a first storage location. A determination is made that previously written data is stored in the first storage location. The previously written data is copied to a second storage location, in response to determining that the previously written data is stored in the first storage location. The data is written to the first storage location, in response to copying the previously written data to the second storage location.

Abstract: A method for use of a physical data storage medium, the method including receiving a first read request for data stored in any of a plurality of storage sub-units on a physical data storage medium, and decrypting the requested data if an indicator associated with the requested data storage sub-unit indicates that data in the requested storage sub-unit is encrypted.

Abstract: Method, device and computer program product for determining a characteristic of an identifiable component. The method includes: receiving identification information representative of an identity of components that belong to a group of components, determining at least one characteristic of an identifiable component in response to the received identification information, and performing at least one characteristic responsive operation. The device includes an identifiable component and a component characteristic determiner. The component characteristic determiner is adapted to receive identification information representative of an identity of components that belong to a group of components and to determine at least one characteristic of the identifiable component in response to a relationship between the received identification information and reference identification information. The device is adapted to perform at least one characteristic responsive information.

Abstract: A method of recovery from a data storage system failure in a data storage system having a host computer writing data to a first storage unit with a first storage controller synchronously mirroring the data to a second storage unit, and with a second storage controller asynchronously mirroring the data to a third storage unit. Upon detection of an error or failure associated with the first storage unit, the synchronous data mirroring relationship between the first storage unit and the second storage unit is terminated and the host is directed to write data updates directly to the second storage unit. Upon correction of the failure associated the asynchronous mirroring of data updates from the second storage unit to the third storage unit is suspended and synchronous mirroring of the data updates in a reverse direction, from the second storage unit to the first storage unit, is commenced.

Abstract: Provided are a method, system, and program for forming a consistency group of data. Information is provided on a consistency group relationship indicating a plurality of slave controllers and, for each indicated slave controller, a slave storage unit managed by the slave controller. A command is transmitted to each slave controller in the consistency group relationship to cause each slave controller to transmit data in the slave storage unit to a remote storage in a manner that forms the consistency group. A determination is made as to whether all the slave controllers successfully transmitted the data in the slave storage units that is part of the consistency group to the remote storage.