Abstract: Storage systems store data in a storage pool comprising storage devices or virtual devices. The storage pool may be allocated for a particular purpose. If a virtual device within the storage pool needs to be repurposed, the virtual device is removed from the storage pool. Data is moved from the removed virtual device to one or more target virtual devices. Segments of the source virtual device being removed are copied to target virtual devices. Mapping tables associating source segments with target segments are stored. If the storage system receives a request to access data stored on a virtual device that is removed, the storage system processes the mapping tables to determine where the data is stored.

Abstract: A database storage system creates secure snapshots or virtual databases based on a source database that stores sensitive information. The database storage system applies a masking function to the sensitive data and stores the masked data in the secure snapshot. The database storage system creates secure snapshots that share masked database blocks with other secure snapshots. The database storage system shares masked database blocks by storing information identifying a previously created masked database block for a new secure snapshot. If a masked database block for the new secure snapshot is different from the previously created masked database block, the database storage system stores metadata including the difference between the two masked database blocks. The database storage system allows sharing any transformed database blocks across snapshot, if the transformed database blocks are obtained by applying a transformation function to data of the source database.

Abstract: A storage system maintains copies of a source database to allow virtual databases to be provisioned. Transaction logs received from the source database are applied to database blocks stored in the storage system to update the database blocks. The storage system checks if there are defect in the transaction logs of the source database. If a defect in transaction logs is detected, the storage system obtains a latest copy of the source database. The storage system matches database blocks of the received copy with database blocks already available in the storage system to determine whether a corresponding database block is already available in the storage system. If a received database block is different from database blocks already available at the storage system, the received database block is stored in the storage system. The database blocks may be matched using a hash value of the database blocks.

Abstract: Virtual databases are provisioned using point-in-time copies of a source database. Transaction logs received from the source database are applied to a point-in-time copy of the source database to create recovery milestones comprising database blocks that can be used to provision virtual databases. The recovery milestones are created in advance of receiving a request to provision a virtual database. Each recovery milestone is validated to determine that a consistent database snapshot can be created using the recovery milestone. If a problem is identified that prevents creation of a consistent database snapshot, the problem is fixed before creating the next recovery milestone. In response to receiving a request to provision a virtual database corresponding to a point in time, a recovery milestone is identified and transaction logs applied to the recovery milestone to create a database snapshot corresponding to the requested point in time.

Abstract: A source storage system replicates snapshots stored on the source storage system to a target storage system. The source storage system stores a plurality of snapshots. The source storage system also stores parent child relationships between snapshots. The source storage system allows child snapshots of a parent snapshot to be modified independent of each other. The source storage system determines changed blocks of a snapshot compared to a previously transmitted snapshot and sends only the changed blocks to the target storage system. The source storage system determines the changed blocks of a snapshot compared to a previously replicated snapshot based on time of creation of a common ancestor of two snapshots. The source storage system transmits a data block of a snapshot if either the data block or a corresponding data block of the previously replicated snapshot was modified after the creation of the common ancestor snapshot.

Abstract: A database storage system creates secure snapshots or virtual databases based on a source database that stores sensitive information. The database storage system applies a masking function to the sensitive data and stores the masked data in the secure snapshot. The database storage system creates secure snapshots that share masked database blocks with other secure snapshots. The database storage system shares masked database blocks by storing information identifying a previously created masked database block for a new secure snapshot. If a masked database block for the new secure snapshot is different from the previously created masked database block, the database storage system stores metadata including the difference between the two masked database blocks. The database storage system allows sharing any transformed database blocks across snapshot, if the transformed database blocks are obtained by applying a transformation function to data of the source database.

Abstract: A source storage system replicates snapshots stored on the source storage system to a target storage system. The source storage system stores a plurality of snapshots. The source storage system also stores parent child relationships between snapshots. The source storage system allows child snapshots of a parent snapshot to be modified independent of each other. The source storage system determines changed blocks of a snapshot compared to a previously transmitted snapshot and sends only the changed blocks to the target storage system. The source storage system determines the changed blocks of a snapshot compared to a previously replicated snapshot based on time of creation of a common ancestor of two snapshots. The source storage system transmits a data block of a snapshot if either the data block or a corresponding data block of the previously replicated snapshot was modified after the creation of the common ancestor snapshot.

Abstract: Virtual databases are provisioned using point-in-time copies of a source database. Transaction logs received from the source database are applied to a point-in-time copy of the source database to create recovery milestones comprising database blocks that can be used to provision virtual databases. The recovery milestones are created in advance of receiving a request to provision a virtual database. Each recovery milestone is validated to determine that a consistent database snapshot can be created using the recovery milestone. If a problem is identified that prevents creation of a consistent database snapshot, the problem is fixed before creating the next recovery milestone. In response to receiving a request to provision a virtual database corresponding to a point in time, a recovery milestone is identified and transaction logs applied to the recovery milestone to create a database snapshot corresponding to the requested point in time.

Abstract: Virtual databases are provisioned using point-in-time copies of a source database. Transaction logs received from the source database are applied to a point-in-time copy of the source database to create recovery milestones comprising database blocks that can be used to provision virtual databases. The recovery milestones are created in advance of receiving a request to provision a virtual database. Each recovery milestone is validated to determine that a consistent database snapshot can be created using the recovery milestone. If a problem is identified that prevents creation of a consistent database snapshot, the problem is fixed before creating the next recovery milestone. In response to receiving a request to provision a virtual database corresponding to a point in time, a recovery milestone is identified and transaction logs applied to the recovery milestone to create a database snapshot corresponding to the requested point in time.

Abstract: A storage system maintains copies of a source database to allow virtual databases to be provisioned. Transaction logs received from the source database are applied to database blocks stored in the storage system to update the database blocks. The storage system checks if there are defect in the transaction logs of the source database. If a defect in transaction logs is detected, the storage system obtains a latest copy of the source database. The storage system matches database blocks of the received copy with database blocks already available in the storage system to determine whether a corresponding database block is already available in the storage system. If a received database block is different from database blocks already available at the storage system, the received database block is stored in the storage system. The database blocks may be matched using a hash value of the database blocks.

Abstract: Virtual databases are provisioned using point-in-time copies of a source database. Transaction logs received from the source database are applied to a point-in-time copy of the source database to create recovery milestones comprising database blocks that can be used to provision virtual databases. The recovery milestones are created in advance of receiving a request to provision a virtual database. Each recovery milestone is validated to determine that a consistent database snapshot can be created using the recovery milestone. If a problem is identified that prevents creation of a consistent database snapshot, the problem is fixed before creating the next recovery milestone. In response to receiving a request to provision a virtual database corresponding to a point in time, a recovery milestone is identified and transaction logs applied to the recovery milestone to create a database snapshot corresponding to the requested point in time.