In a storage system in which a plurality of pieces of control software constituting a redundancy group are distributedly arranged in a plurality of storage nodes, control software in an active state out of the plurality of pieces of control software constituting the redundancy group receives a write request from a higher-level device. The control software in the active state writes data related to the write request by mirroring into a cache memory of a storage node in which the control software in the active state is arranged and a cache memory of a storage node in which control software in an inactive state belonging to the same redundancy group is arranged. The control software in the active state sends a write completion response to the higher-level device, and redundantly stores the data written in the cache memories in a storage device.

Methods, computer program products, computer systems, and the like are disclosed that provide for scalable deduplication in an efficient and effective manner. For example, such methods, computer program products, and computer systems can include determining whether a source data store and a replicated data store are unsynchronized and, in response to a determination that the source data store and the replicated data store are unsynchronized, performing a resynchronization operation. The source data stored in the source data store is replicated to replicated data in the replicated data store. The resynchronization operation resynchronizes the source data and the replicated data.

Examples of the present disclosure describe implementing bitmap-based data replication when a primary form of data replication between a source device and a target device cannot be used. According to one example, a temporal identifier may be received from the target device. If the source device determines that the primary replication method is unable to be used to replicate data associated with the temporal identifier, a secondary replication method may be initiated. The secondary replication method may utilize a recovery bitmap identifying data blocks that have changed on the source device since a previous event.

A database can be instantly recovered by a cluster mapped to the database. Nodes of the cluster are mapped over channels to directories of the database. Scripts are generated from one or more templates that specify the order and values to be executed to perform a database job, such as database recovery. To recover the database, a template is executed that generates and populates scripts, which are processed on the host of the database to recover the database in a nearly instant manner without transferring data files.

Techniques provide for data synchronization. For example, such a technique may involve: obtaining respective synchronization characteristics of a group of synchronization jobs to be processed, each synchronization characteristic indicating at least one of an expected completion time instant and an amount of data to be synchronized of a corresponding synchronization job; prioritizing the group of the synchronization jobs based on the synchronization characteristics; and controlling execution of the group of the synchronization jobs based on a result of the prioritizing. Accordingly, high priority is given to the synchronization jobs which can be rapidly completed thereby improving the Recovery Point Objective (RPO) achievement rate before occurrence of a failure.

A method and apparatus for performing disk management of an all flash array (AFA) server are provided. The method may include: utilizing a disk manager module among multiple program modules running on any node of multiple nodes of the AFA server to trigger a hardware layer of the any node to perform disk switching control in HA architecture of the AFA server, for controlling the any node to enable a set of disk switching paths between the any node and a group of storage devices among multiple sets of disk switching paths between the multiple nodes and multiple groups of storage devices; and utilizing the disk manager module to perform multiple groups of operations respectively corresponding to multiple disk pools in a parallel processing manner, for managing the group of storage devices with the multiple disk pools, wherein the multiple disk pools may include active, inserted, and failure disk pools.

Managing connectivity to synchronously replicated storage systems, including: identifying a plurality of storage systems across which a dataset is synchronously replicated; identifying a host that can issue I/O operations directed to the dataset; identifying a plurality of data communications paths between the host and the plurality of storage systems across which a dataset is synchronously replicated; identifying, from amongst the plurality of data communications paths between the host and the plurality of storage systems across which a dataset is synchronously replicated, one or more optimal paths; and issuing, to the host, an identification of the one or more optimal paths.

Techniques are provided for resynchronizing a synchronous replication relationship. Asynchronous incremental transfers are performed to replicate data of a storage object to a replicated storage object. Incoming write requests, targeting the storage object, are logged into a dirty region log during a last asynchronous incremental transfer. Metadata operations, executed on the storage object, are logged into a metadata log during the last asynchronous incremental transfer. Sequence numbers are assigned to the metadata operations based upon an order of execution. The metadata operations are replicated to the replicated storage object for execution according to the sequence numbers, and the dirty regions are replicated to the replicated storage object in response to the metadata operations having been replicated to the replicated storage object. The storage object and replicated storage object are transitioned to a synchronous replication state where incoming operations are synchronously replicated to the replicated storage object.

Provided are a data management method for a distributed storage system, an apparatus, and an electronic device. The method comprises: sending to each storage server a first request for acquiring data copy information; and according to the data copy information returned by each storage server in response to the first request, updating mapping data used to reflect the correspondence between the data copy information and the storage servers.

Techniques are provided for caching data during an on-demand restore using a cloud block map. A client may be provided with access to an on-demand volume during a restore process that copies backup data from a snapshot within a remote object store to the on-demand volume stored within local storage. In response to receiving a request from the client for a block of the backup data not yet restored from the snapshot to the on-demand volume, the block may be retrieved from the snapshot in the remote object store. The block may be cached within a cloud block map stored within the local storage as a cached block. The client may be provided with access to the cached block.