Abstract: Techniques for managing a file system involve in response to receiving, at a first backup device of the file system, a request for replicating data of the file system from the first backup device to a second backup device of the file system, determining a synchronization state between the first backup device and the file system, the second backup device being a backup device located downstream of the first backup device; creating, based on the synchronization state, a target snapshot associated with the file system; and causing the data to be replicated from the first backup device to the second backup device based on the target snapshot. Therefore, the data backup flexibility and accuracy of a file system can be significantly improved and therefore the reliability of the whole system may be enhanced.

Abstract: Techniques involve: in response to a first session for asynchronous snapshot replication being established between a first source device and a destination device, determining whether the first source device and the destination device have a common baseline snapshot. Such techniques further involve: in response to determining absence of the baseline snapshot, determining whether initial synchronization from a second source device to the destination device is completed. Such techniques further involve: replicating, based on a result of the determining, at least one user snapshot at the first source device to the destination device. Accordingly, duplicated user snapshots at the destination device are significantly reduced. The snapshot management and space utilization of the destination device are also improved.

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: Embodiments of the present disclosure provide a method and device for data duplication cutover. The method includes initiating duplication of initial data from a source device to a destination device, wherein the initial data are data of a file system stored on the source device upon the initiating. The method further includes, in response to completing the duplication of the initial data, updating a session associated with the file system. Furthermore, the method includes, after updating the session, triggering the source device and the destination device into a data unavailable state to perform duplication of delta data from the source device to the destination device, wherein the delta data are data of the file system changed during duplication of the initial data. Utilization of the cutover mechanism proposed in the present disclosure enables effective reduction of data unavailable period of time.

Abstract: Techniques for managing a file system involve in response to receiving, at a first backup device of the file system, a request for replicating data of the file system from the first backup device to a second backup device of the file system, determining a synchronization state between the first backup device and the file system, the second backup device being a backup device located downstream of the first backup device; creating, based on the synchronization state, a target snapshot associated with the file system; and causing the data to be replicated from the first backup device to the second backup device based on the target snapshot. Therefore, the data backup flexibility and accuracy of a file system can be significantly improved and therefore the reliability of the whole system may be enhanced.

Abstract: To monitor data duplication progress, embodiments of the present disclosure relate to a method and apparatus for determining data duplication progress in real-time. The method comprises initiating a duplication of data from a source system to a destination system. The method further comprises determining first duplication progress for an initial stage of the duplication, original data existing on the source system when the duplication is initiated being duplicated in the initial stage. Furthermore, the method further comprises determining, independently from the initial stage, second duplication progress for a delta stage of the duplication, delta data being duplicated in the delta stage and including at least data generated during the initial stage. The present disclosure develops a fine-grained monitoring mechanism of data duplication progress.

Abstract: A method and device for managing sessions comprises obtaining first identification information of a first session of a plurality of sessions and group operation identification information of a group operation to be performed for the plurality of sessions, each of the plurality of sessions replicating, from a source of the session to a destination of the session, a file system or a management system that manages the file system; determining whether the first session meets a condition that a session is suitable to be selected as a managing session, the managing session managing the plurality of sessions to perform the group operation on the plurality of sessions; in response to the first session failing to meet the condition, obtaining second identification information of a second session of the plurality of sessions, the second identification information being different from the first identification information; and selecting the managing session based on the second identification information.

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 method and device for dispatching replication tasks in a network storage device. For instance, a method of dispatching replication tasks in a network storage device includes: in response to receiving a request for replicating a plurality of sessions, dispatching a task for replicating a configuration session among the plurality of sessions to a first processing unit of the network storage device, the configuration session including configuration information describing a plurality of sessions; dispatching a plurality of tasks for replicating other sessions among the plurality of sessions except the configuration session to a plurality of second processing units different from the first processing unit; and in response to the first processing unit and the plurality of second processing units completing the respective tasks, aggregating results of replicating the plurality of sessions. With the technical solution of the present disclosure, processing efficiency can be improved and time can be saved.

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: Techniques involve: in response to a first session for asynchronous snapshot replication being established between a first source device and a destination device, determining whether the first source device and the destination device have a common baseline snapshot. Such techniques further involve: in response to determining absence of the baseline snapshot, determining whether initial synchronization from a second source device to the destination device is completed. Such techniques further involve: replicating, based on a result of the determining, at least one user snapshot at the first source device to the destination device. Accordingly, duplicated user snapshots at the destination device are significantly reduced. The snapshot management and space utilization of the destination device are also improved.

Abstract: Various embodiments of the present disclosure provide a method for presenting a storage cluster status, comprising: in response to a request for monitoring a first target node in a storage cluster, monitoring whether a configuration status of the first target node is changed; and in response to the configuration status of the first target node being changed, presenting changed configuration status information of the first target node to the user.

Abstract: A user I/O operation is processed in a file system of a target data storage system (DSS) performing a file system migration. The target DSS assesses a migration state of a user file of the user I/O operation, including (1) determining whether a metadata file storing migration state data for the user file has an already recovered record indicating the migration state of the file, (2) if so, then using the already recovered record to assess the migration state of the user file, and (3) otherwise (a) initiating an on-demand recovery to obtain an on-demand record for the user file, and (b) using the on-demand recovered record to assess the migration state. If the migration state indicates that the file has not yet been migrated, then the user I/O operation is redirected to a separate source DSS, and otherwise the user I/O operation is completed locally at the target DSS.

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: Embodiments of the present disclosure provide a method and device for data duplication cutover. The method includes initiating duplication of initial data from a source device to a destination device, wherein the initial data are data of a file system stored on the source device upon the initiating. The method further includes, in response to completing the duplication of the initial data, updating a session associated with the file system. Furthermore, the method includes, after updating the session, triggering the source device and the destination device into a data unavailable state to perform duplication of delta data from the source device to the destination device, wherein the delta data are data of the file system changed during duplication of the initial data. Utilization of the cutover mechanism proposed in the present disclosure enables effective reduction of data unavailable period of time.

Abstract: A method and device for managing sessions comprises obtaining first identification information of a first session of a plurality of sessions and group operation identification information of a group operation to be performed for the plurality of sessions, each of the plurality of sessions replicating, from a source of the session to a destination of the session, a file system or a management system that manages the file system; determining whether the first session meets a condition that a session is suitable to be selected as a managing session, the managing session managing the plurality of sessions to perform the group operation on the plurality of sessions; in response to the first session failing to meet the condition, obtaining second identification information of a second session of the plurality of sessions, the second identification information being different from the first identification information; and selecting the managing session based on the second identification information.

Abstract: A method and device for dispatching replication tasks in a network storage device. For instance, a method of dispatching replication tasks in a network storage device includes: in response to receiving a request for replicating a plurality of sessions, dispatching a task for replicating a configuration session among the plurality of sessions to a first processing unit of the network storage device, the configuration session including configuration information describing a plurality of sessions; dispatching a plurality of tasks for replicating other sessions among the plurality of sessions except the configuration session to a plurality of second processing units different from the first processing unit; and in response to the first processing unit and the plurality of second processing units completing the respective tasks, aggregating results of replicating the plurality of sessions. With the technical solution of the present disclosure, processing efficiency can be improved and time can be saved.

Abstract: To monitor data duplication progress, embodiments of the present disclosure relate to a method and apparatus for determining data duplication progress in real-time. The method comprises initiating a duplication of data from a source system to a destination system. The method further comprises determining first duplication progress for an initial stage of the duplication, original data existing on the source system when the duplication is initiated being duplicated in the initial stage. Furthermore, the method further comprises determining, independently from the initial stage, second duplication progress for a delta stage of the duplication, delta data being duplicated in the delta stage and including at least data generated during the initial stage. The present disclosure develops a fine-grained monitoring mechanism of data duplication progress.

Abstract: Various embodiments of the present disclosure provide a method for presenting a storage cluster status, comprising: in response to a request for monitoring a first target node in a storage cluster, monitoring whether a configuration status of the first target node is changed; and in response to the configuration status of the first target node being changed, presenting changed configuration status information of the first target node to the user.

Abstract: A storage system failure detection and failover application includes a command execution engine that loads and interprets both user-defined storage system management functions, and vendor-defined storage system management functions. The user-defined storage system management functions allow the system to detect and handle failure conditions indicating both the current state of an active storage system, and the current state of one or more applications that consume a storage service or services provided by the active storage system. The user-defined storage management functions also allow the system to perform failover processing in a way that allows applications to perform application-specific processing during storage system failover.