Systems and methods for providing and/or facilitating live browsing of granular mail or mailbox data, such as data stored within Exchange mailboxes, are described. For example, the systems and methods may provide mechanisms for browsing and/or restoring granular data (e.g., email data) from an Exchange database backup copy (or other secondary copy), without having to restore the entire database from the backup copy.

Candidate duplicate events are identified as they are executed via data replication within a distributed system. A periodicity of the identified candidate duplicate events is identified. In response to identifying the periodicity, a delay is introduced into execution of a first event related to the candidate duplicate event. A feedback loop of the distributed system is identified based on an observed delay in the timing of another event of the candidate duplicate events.

A backup system includes a processor and a machine-readable storage storing instructions. The instructions are executable by the processor to: access a plurality of blocks included in a block-based backup of a first snapshot of a storage volume; determine, based on the plurality of blocks of the block-based backup, a first filesystem stored on the storage volume, the first filesystem being a first type of filesystem; select, from a plurality of filters, a first filter associated with the first type of filesystem; determine a changed file in the first filesystem based on the selected first filter; and update a catalog to indicate that the changed file is associated with the first snapshot.

A storage system includes a nonvolatile memory device and a controller. The nonvolatile memory device includes first and second memory blocks and stores data corresponding to first and second volumes. The controller performs a snapshot function on the data corresponding to the first and second volumes and determines data to be stored in the first and second memory blocks based on parameters for generating snapshots of the first and second volumes. The controller stores data corresponding to a snapshot deleted at a first time point in the first memory block, stores data corresponding to a snapshot deleted at a second time point in the second memory block, adds the first memory block to a victim block list after the first time point, and adds the second memory block to the victim block list after the second time point.

The disclosed systems and methods enable an application to start operating and servicing users soon after and during the course of its backup data being restored, no matter how long the restore may take. This is referred to as “instant application recovery” in view of the fact that the application may be put back in service soon after the restore operation begins. Any primary data generated by the application during “instant application recovery” is not only retained, but is efficiently updated into restored data. An enhanced data agent and an associated pseudo-storage-device driver, which execute on the same client computing device as the application, enable the application to operate substantially concurrently with a full restore of backed up data. According to the illustrative embodiment, the pseudo-storage-device driver presents a pseudo-volume to the file system associated with the application, such that the pseudo-volume may be used as a store for primary data during the period of “instant application recovery.”

A data write control method includes detecting a quantity of dirty blocks in a first memory when a write control apparatus is in write-back mode; separately predicting execution progress of a program run by a processor within a danger time period in the two write modes when the quantity of dirty blocks reaches a first preset threshold; when it is predicted that the execution progress of the program run by the processor within the danger time period in write-through mode is faster than the execution progress of the program run by the processor within the danger time period in write-back mode, switching a current data write mode to the write-through mode; and detecting the quantity of dirty blocks when the write control apparatus is in write-through mode and switching the current data write mode to the write-back mode when the quantity of dirty blocks decreases to a second preset threshold.

A checkpointing method in a network device fault tolerant system using virtual machines. In one embodiment, the network device has an input port, an output port, an active virtual machine and a standby virtual machine, a network application on the active virtual machine which manipulates data present on the input port and transmits the manipulated data from the output port; a checkpoint engine on the active virtual machine; and an interface agent, on the active virtual machine, having callable functions to move data from the input port to the output port. The method includes the steps of determining, by the checkpoint engine, that a checkpoint is required; requesting by the checkpoint engine that the interface agent quiescent itself; returning, by the interface agent to the network application, an indicator that no packets are available regardless of whether or not packets are arriving at the input port.

Due to the threat of virus attacks and ransom ware, an apparatus and methods for protecting backup storage devices from malicious software virus attacks is explored. An independent backup storage system is connected to a primary storage server over an undiscoverable communications line. The backup storage system is a read-only backup storage system most of the time buffering the backup storage system from a virus or attack on the primary storage server. The backup storage system changes from a read-only backup storage system to a read/write backup storage system only during a backup window of time where data is backed up to the backup storage system. A snapshot of the backup data is maintained in the backup storage system and can be made available at numerous points of time in the past if the data primary storage server becomes corrupted.

A method for synchronous replication of stream data includes receiving a stream of data blocks for storage at a first storage location associated with a first geographical region and at a second storage location associated with a second geographical region. The method also includes synchronously writing the stream of data blocks to the first storage location and to the second storage location. While synchronously writing the stream of data blocks, the method includes determining an unrecoverable failure at the second storage location. The method also includes determining a failure point in the writing of the stream of data blocks that demarcates data blocks that were successfully written and not successfully written to the second storage location. The method also includes synchronously writing, starting at the failure point, the stream of data blocks to the first storage location and to a third storage location associated with a third geographical region.

A method for loading an assembly for a CAx client includes determining referenced part IDs referenced by the assembly and for each referenced part ID, determining a latest applied command of saved checkpoints for each part file of a referenced part ID. The method further includes determining any unapplied commands for each referenced part ID, loading the part file for each referenced part ID with the latest applied command to the CAx client, and applying the unapplied commands sequentially by command number. A computer program product such as a computer readable medium and a computer system corresponding to the above method are also disclosed herein.