Abstract: Techniques manage application systems in an application environment. The application environment includes a first application system, a second application system and a third application system. First snapshot information of a first group of snapshots of the first application system is obtained, the first application system being in active state. Second snapshot information of a second group of snapshots of the second application system is obtained, the second application system being in standby state. It is determined whether the second application system and the third application system have a common snapshot based on the first snapshot information and the second snapshot information. Data is synchronized to the third application system depending on whether the second application system and the third application system have a common snapshot. Overheads required during data synchronization may be reduced as far as possible, and the efficiency of data synchronization may be improved.

Abstract: A method of performing synchronous replication from a primary storage system apparatus (PSSA) to a secondary storage system apparatus (SSSA) is provided. The method includes (a) in response to write requests received by the PSSA, (i) calculating metadata changes by the PSSA for accommodating the write requests, (ii) generating, by the PSSA, metadata journal log entries that describe the metadata changes, and (iii) mirroring the metadata journal log entries from the PSSA to the SSSA; (b) regenerating the metadata changes by the SSSA based on the metadata journal log entries mirrored from the PSSA to the SSSA; and (c) writing the regenerated metadata changes to persistent storage of the SSSA. A method performed by the SSSA is also provided. An apparatus, system, and computer program product for performing similar methods are also provided.

Abstract: Embodiments of the present disclosure provide a method, a computer program product and apparatus for processing transactions in a synchronized replication system, wherein the method comprises, at a source site in the synchronized replication system: serializing commits of transactions in the synchronized replication system so that only one of the transactions can be committed at the same time; in response to initiating the commit of the one transaction, generating a log for each of transactions that are ongoing in the synchronized replication system, so as to record impact of all operations of a respective transaction on the synchronized replication system; marking transactions for which the logs have been generated; and completing commits of the marked transactions.

Abstract: A method is used for bitmap-based synchronous replication in a data protection system. The method includes, upon re-establishing communication with a first storage node, requesting, by a second storage node, a first bitmap from the first storage node. The method includes determining, by the second storage node, a set of data blocks to change on the first storage node based on the first bitmap and a second bitmap on the second storage node. The method also includes sending, by the second storage node to the first storage node, the set of data blocks.

Abstract: Techniques perform data backup. Such techniques involve: in response to a first storage node to be switched to a second storage node, determining whether there is an ongoing data backup operation between the first storage node and a third storage node; and in response to the ongoing data backup operation between the first and third storage nodes, ceasing the data backup operation. The second storage node is used for backing up data of the first storage node in real time and the third storage node is used for backing up the data of the first storage node periodically. Accordingly, colliding operations can be prevented, system resource can be saved and processing efficiency can be improved.

Abstract: Task management techniques, in a storage system, involve: dividing a task to be processed into a plurality of child tasks, so that a processing time required by each of the plurality of child tasks is same, the number of the plurality of child tasks being a first number; dividing a progress to be reported and being associated with the processing of the task into a plurality of child progresses, the number of the plurality of the child progresses being a second number, the second number being less than the first number, and each of the plurality of child progresses having a same value; and associating, based on the first and the second number, and according to a predetermined mapping between the plurality of child progresses and the plurality of child tasks, each of the plurality of child progresses with a respective child task of the plurality of child tasks.

Abstract: A method is used for bitmap-based synchronous replication in a data protection system. The method includes, upon re-establishing communication with a first storage node, requesting, by a second storage node, a first bitmap from the first storage node. The method includes determining, by the second storage node, a set of data blocks to change on the first storage node based on the first bitmap and a second bitmap on the second storage node. The method also includes sending, by the second storage node to the first storage node, the set of data blocks.

Abstract: Techniques manage application systems in an application environment. The application environment includes a first application system, a second application system and a third application system. First snapshot information of a first group of snapshots of the first application system is obtained, the first application system being in active state. Second snapshot information of a second group of snapshots of the second application system is obtained, the second application system being in standby state. It is determined whether the second application system and the third application system have a common snapshot based on the first snapshot information and the second snapshot information. Data is synchronized to the third application system depending on whether the second application system and the third application system have a common snapshot. Overheads required during data synchronization may be reduced as far as possible, and the efficiency of data synchronization may be improved.

Abstract: Techniques perform data synchronization. The techniques involve: in response to writing of data to a source storage array, determining whether a transmission link between the source storage array and a destination storage array is disconnected, the data being to be synchronized to the destination storage array; in response to determining that the transmission link is disconnected, accumulating in the source storage array the data written to the source storage array; in response to detecting that the transmission link is recovered, creating a snapshot for a storage unit associated with the data in the destination storage array; and in response to crashing of the source storage array during resynchronization of the data accumulated in the source storage array to the storage unit, restoring the storage unit in the destination storage array using the snapshot. Therefore, the storage space for the snapshot is greatly saved while disaster recovery is ensured.

Abstract: Embodiments of the present disclosure provide a method and device for a storage system. The method may include: replicating, through a first replication process, data in a first storage device to a second storage device to obtain a data replica; replicating, through a second replication process, metadata of the data to the second storage device to obtain a first metadata replica; replicating, in the second storage device through a third replication process, the first metadata replica to obtain a second metadata replica; and performing data recovery based on the data replica and the second metadata replica.

Abstract: Embodiments of the present disclosure provide a computer program product, a system and a method for providing access to storage resources by receiving a user selection of one or more of a plurality of source storage resources; establishing corresponding backup storage resources for the selected one or more source storage resources.

Abstract: A technique preserves replication to a storage node. The technique involves, from a first storage node, sending a replication query to a second storage node. The technique further involves, in response to the replication query sent to the second storage node, receiving replication session data from the second storage node. The replication session data describes replication which has terminated from a third storage node to the second storage node for a particular storage object. The technique further involves, based on the replication session data, establishing replication from the first storage node to the second storage node for the particular storage object to preserve use of the particular storage object.

Abstract: A technique preserves replication to a storage node. The technique involves, from a first storage node, sending a replication query to a second storage node. The technique further involves, in response to the replication query sent to the second storage node, receiving replication session data from the second storage node. The replication session data describes replication which has terminated from a third storage node to the second storage node for a particular storage object. The technique further involves, based on the replication session data, establishing replication from the first storage node to the second storage node for the particular storage object to preserve use of the particular storage object.

Abstract: Embodiments of the present disclosure relate to a method, a computer program products and apparatus for controlling sharing of a resource among a plurality of nodes, wherein in response to a service using the resource to be initiated at an object node of the plurality of nodes, locking, at the object node, an object file that is associated with use of the resource; in response to successful locking of the object file, determining, at the object node, whether other files associated with the use of the resource at other nodes of the plurality of nodes have been locked; and in response to determining that the other files are not locked, using, at the object node, the resource to initiate the service.

Abstract: Task management techniques, in a storage system, involve: dividing a task to be processed into a plurality of child tasks, so that a processing time required by each of the plurality of child tasks is same, the number of the plurality of child tasks being a first number; dividing a progress to be reported and being associated with the processing of the task into a plurality of child progresses, the number of the plurality of the child progresses being a second number, the second number being less than the first number, and each of the plurality of child progresses having a same value; and associating, based on the first and the second number, and according to a predetermined mapping between the plurality of child progresses and the plurality of child tasks, each of the plurality of child progresses with a respective child task of the plurality of child tasks.

Abstract: Techniques perform data backup. Such techniques involve: in response to a first storage node to be switched to a second storage node, determining whether there is an ongoing data backup operation between the first storage node and a third storage node; and in response to the ongoing data backup operation between the first and third storage nodes, ceasing the data backup operation. The second storage node is used for backing up data of the first storage node in real time and the third storage node is used for backing up the data of the first storage node periodically. Accordingly, colliding operations can be prevented, system resource can be saved and processing efficiency can be improved.

Abstract: The present disclosure provides a method and an apparatus for a storage system. The storage system includes an active storage site and a standby storage site, and a logical unit number LUN for a storage pool of the active storage site is replicated to a LUN for a storage pool of the standby storage site to form a consistency group. The method comprises: creating a first LUN and a second LUN as mirrors of each other at the active storage site and the standby storage site, respectively; adding the mirrors formed by the first LUN and the second LUN to the consistency group; after the second LUN is added to the storage pool of the standby storage site, adding the first LUN to the storage pool of the active storage site.

Abstract: Techniques perform data synchronization. The techniques involve: in response to writing of data to a source storage array, determining whether a transmission link between the source storage array and a destination storage array is disconnected, the data being to be synchronized to the destination storage array; in response to determining that the transmission link is disconnected, accumulating in the source storage array the data written to the source storage array; in response to detecting that the transmission link is recovered, creating a snapshot for a storage unit associated with the data in the destination storage array; and in response to crashing of the source storage array during resynchronization of the data accumulated in the source storage array to the storage unit, restoring the storage unit in the destination storage array using the snapshot. Therefore, the storage space for the snapshot is greatly saved while disaster recovery is ensured.

Abstract: Embodiments are directed to techniques for enforcing prerequisite conditions on a data object for an operational feature both upon initiation of that operational feature and while that operational feature is maintained. Accordingly, improved techniques enforce conditions by setting a flag associated with a data object upon confirming that the conditions have been met and checking the flag anytime a configuration change to the data object is requested that would cause the conditions to be violated. If the flag is set, any configuration change that would cause the conditions to be violated is rejected.

Abstract: Replication techniques for file-based replication. A first file pool and a second pool may be created, respectively, on a first site and a second site. Storage for the first file pool may be provisioned from a first storage device group configured as a first consistency group. Storage for the second file pool may be provisioned from a second storage device group configured as a second consistency group. Modification operations, such as writes, may be applied to the first file pool. The modifications performed on the first file pool result in corresponding modifications to the first consistency group. The modifications may be replicated on the second file pool by applying the modifications to the second consistency group. File systems created in the first and second file pools may be self-contained and modifications applied to the first and second consistency groups may be applied in a specified order to ensure write consistency.