83 results about "File replication" patented technology

Methods and systems for efficient file replication are provided. In some embodiments, one or more coarse signatures for blocks in a base file are compared with those coarse signatures for blocks of a revised file, until a match is found. A fine signature is then generated for the matching block of the revised file and compared to a fine signature of the base file. Thus, fine signatures are not computed unless a coarse signature match has been found, thereby minimizing unneeded time-consuming fine signature calculations. Methods are also provided for determining whether to initiate a delta file generation algorithm, or whether to utilize a more efficient replication method, based upon system and / or file parameters. In accordance with additional embodiments, the lengths of valid data on physical blocks are obtained from physical block mappings for the files, and these lengths and mappings are utilized for delta file generation, to minimize unnecessary signature computations.

A data replication facility for distributed computing environments. A computer network having a plurality of network nodes utilizes a distributed directory provider service (DPS) having an established master node. The DPS supports a file replication service (FRS). The FRS establishes one of the nodes as originator node which receives new or updated files from one or more user / GUIs and / or from one or more software providers such as a security provider. The originator node in cooperation with the master node establish a backup copy of the new or updated file in the master node. Thereafter, the originator node publishes a File Version Variable (FVV) representation of the new or updated file to other network nodes (slave nodes) which obtain such file from the originator or, if need be, from the backup master node. Object observers are utilized to determine changes to the file version variables thereby triggering the downloading of new or updated files into the network nodes, whereby data file replication is accomplished throughout the network. In addition to avoiding a single point of failure, embodiments of the present invention also are network-topology independent. Additional syncing threads are employed as part of the file replication service to further ensure synchronization of the network nodes' data files within a predetermined interval, regardless of network failure modes. Embodiments of the present invention are particularly useful with networks of the client-server storage network variety.

Client and server based copies of a file are maintained in synchronicity as changes are made to the file. Data is compared to a previous version known to both the client and server and a highly compressed representation of the differences between the two is generated. These differences, or “diffs”, are then transmitted, and may use extensions to the HTTP (HyperText Transport Protocol) protocol.

A NAS switch, in the data path of a client and a NAS file server on the storage network, provides a centralized point of reconfiguration after a network change that alleviates the need for reconfiguration of each connected client. The client uses a NAS request to access a storage object to the NAS switch using a switch file handle that is independent of object location and that can be used to locate the primary and its replica storage objects if the object is subsequently replicated. A replication module replicates a namespace separately from data contained therein. Afterwards, synchronicity module looks-up the switch file handle in a file handle replication table to determine if the object has been replicated and, if so, sends one of the replica NAS file handles. The synchronicity module also maintains synchronicity between the primary and replica file servers through critical NAS requests that modify objects such as create, delete, and the like.

A storage object such as a virtual disk drive or a raw logical volume is contained in a UNIX compatible file so that the file containing the storage object can be exported using the NFS or CIFS protocol and shared among UNIX and MS Windows clients or servers. The storage object can be replicated and backed up using conventional file replication and backup facilities without disruption of client access to the storage object. For client access to data of the storage object, a software driver accesses the file containing the storage object. For example, a software driver called a virtual SCSI termination is used to access a file containing a virtual SCSI disk drive. Standard storage services use the SCSI over IP protocol to access the virtual SCSI termination. An IP replication or snapshot copy facility may access the file containing the virtual SCSI disk drive using a higher-level protocol.