111 results about "Secondary site" patented technology

A method and system is disclosed to maintain data consistency over an internet small computer system interface (iSCSI) network, for disaster recovery and remote data replication purposes. Data consistency and replication is maintained between primary and secondary sites geographically distant from each other. According to the method, a primary journal volume logs all changes (data writes) made to a primary volume, transmits the changes based on a preconfigured policy to a secondary journal volume, and thereafter merges the changes stored in the secondary journal volume with a secondary volume. Changes in the journal volumes are ordered in point-in-time (PiT) frames and transmitted using a vendor specific SCSI command utilizing the iSCSI protocol.

In an asynchronous remote copy system, a primary site keeps a list of data blocks for which changes have been made to a primary file system and transmitted to a secondary file system at a secondary site. When the primary site becomes inoperative, the secondary site begins read / write access to the secondary file system and keeps a snapshot copy of the restart point. Once the primary site becomes operative, the primary file system is restored to the state of the secondary file system at the restart point by using the list of data blocks for obtaining from the snapshot copy the data of the blocks for which changes had been made to the primary file system after the restart point. Then the primary file system is synchronized to the secondary file system, and read / write access is switched back from the secondary file system to the primary file system.

In an asynchronous remote copy system, a primary site keeps a list of data blocks for which changes have been made to a primary file system and transmitted to a secondary file system at a secondary site. When the primary site becomes inoperative, the secondary site begins read / write access to the secondary file system and keeps a snapshot copy of the restart point. Once the primary site becomes operative, the primary file system is restored to the state of the secondary file system at the restart point by using the list of data blocks for obtaining from the snapshot copy the data of the blocks for which changes had been made to the primary file system after the restart point. Then the primary file system is synchronized to the secondary file system, and read / write access is switched back from the secondary file system to the primary file system.

Server virtualization technology is applied to virtualize and encapsulate all unique information of a server as an image that is stored on a storage area network at one site and replicated on a storage area network at another site to provide high availability of system resources and data recovery capabilities. In one embodiment, a virtualized server system (100) includes a primary site (110), a secondary site (130), and a computer executable control application (150). The primary site (110) includes a storage area network (112), at least one primary virtual server platform (114), and at least one primary virtual server stored as at least one image (116) on the storage area network (112). The control application (150) directs replication of the primary virtual server image (116) onto a storage area network (132) at the secondary site (130) to create a corresponding replicated virtual server image (138). The control application (150) also monitors operation of the primary virtual server platform (114) and associates the replicated virtual server image (138) with a secondary virtual server (134) at the secondary site (130) in the event that a problem is detected with the primary site virtual server (114).

High speed differential copy can be implemented in the fail-back after disaster recovery when the data of the primary site is protected safely. When a restore command is issued, the common snapshots of the snapshots of the primary site and the secondary site are extracted as the base snapshot by comparing the log tables of the primary site and secondary site. The volume of the primary site is rolled back with the extracted snapshots. The latest snapshot of the volume of the secondary site is transmitted to the primary site and it is applied to the volume of the primary site to synchronize the volumes of the primary site and the secondary site.

A method, system, and computer program product for ordering a plurality of data IO captured at a primary site to be applied at a secondary site, comprising removing the one or more extent level portions from the captured data IO, determining if the one or more extent level portions are time sequenced to overwrite a portion of data of the data IO, based on a determination that the portion data is to be overwritten, removing the overwritten portion of data from the plurality of the data IO and ordering the one or more extent level portions to be applied at the secondary site before the captured data IO.

A processing system stores a backup of virtual machine data on a storage device in a primary network storage system. A virtual machine running on a primary host machine, which is coupled to the primary network storage system, generates the virtual machine data. A replication software module replicates the backup of the virtual machine data from the primary network storage system to a secondary network storage system. In the event of a failure on the first network storage system, disaster recovery services module restores the virtual machine data from the secondary network storage system to cause the virtual machine to run on a secondary host machine coupled to the secondary network storage system, wherein the disaster recovery services module is coupled to the primary host machine and the secondary host machine over a network.

A method for remotely monitoring activity includes generating first server heartbeat information at a first server at a local site, and storing the first server heartbeat information in a first primary site disk at the local site. The method also includes sending the first server heartbeat information from the first primary site disk, to a first secondary site disk at a remote site. The method further includes receiving information from a second secondary site disk at the local site, and determining if the information received from the second secondary site disk includes updated heartbeat information.

High speed differential copy can be implemented in the fail-back after disaster recovery when the data of the primary site is protected safely. When a restore command is issued, the common snapshots of the snapshots of the primary site and the secondary site are extracted as the base snapshot by comparing the log tables of the primary site and secondary site. The volume of the primary site is rolled back with the extracted snapshots. The latest snapshot of the volume of the secondary site is transmitted to the primary site and it is applied to the volume of the primary site to synchronize the volumes of the primary site and the secondary site.

A source storage server receives various write requests from a set of clients, logs each request in local memory, and forwards each log entry to a destination storage server at a secondary site. At a consistency point, the source storage server saves data, modified per the requests, to a first set of mass storage devices, and also initiates a synchronization phase during which process the modified data is mirrored at the secondary site. The destination storage server uses data in the received log entries to mirror at least a portion of the modified data in a second set of mass storage devices located at the secondary site, such that said portion of the modified data does not have to be sent from the source storage server to the destination storage server at the consistency point.

A method of restricting access to private keys in a public key infrastructure provides for storage of an encrypted private key at a primary site. A masked session key is stored at a secondary site, where the masked session key enables recovery of the private key. By using distributed storage architecture for recovery data, simplification can be achieved without sacrificing security.

Provided are a method, system, and article of manufacture for using virtual copies in a failover and failback environment. Updates are copied from a primary first storage at the primary site to a secondary first storage at the secondary site during system operations. A second storage is maintained at at least one of the primary and secondary sites. A failover is performed from the primary site to the secondary site after a failure at the primary site. The at least one second storage is used after recovery of the primary site to synchronize the secondary site to the primary site. Only updates made to the secondary site during the failover are copied to or from the at least one second storage in response to the recovery at the primary site.

In the present invention, there is provided means which sets priorities of DB data for each management unit, means which copies data from a primary site to a secondary site in an order of the data priorities, and means which, when a disaster has occurred in the primary site and recovery of a DB is performed in the secondary site, performs recovery of data in the order of the data priorities to sequentially bring the data to a usable state.

To provide a computer system capable of fast failover so that a service is stopped only for a brief period of time from a failure in a first site. The computer system includes a primary site for regular operation and a secondary site that operating when the primary site fails. A primary storage and a secondary storage have a synchronization unit to make contents stored in the primary storage and contents stored in the secondary storage identical to each other. A client has a cache for recording address information (e.g. DNS) that gives the client an access to the server from which the service is provided and information that defines a time to live of the address information. A first server has a primary request log processing unit, which instructs the client to shorten the recorded time to live of the address information when communication with the secondary site is detected to be impossible.

A multi-point communications system is set forth herein. The communications system includes a receiver and transmitter disposed at a primary site for communication with a plurality of remote service units disposed at respective secondary sites. The receiver of the primary site receives OFDM / DMT signals over a number of transmission bins. A transmitter at the remote service unit includes an improved transmitter architecture. The transmitter comprises a first circuit for converting a signal into a first serial digital data stream and a second circuit for generating a second serial digital data stream from the first serial digital data stream of the first means. The second serial digital data stream is a digital representation of an OFDM / DMT signal that is to be transmitted to the receiver of the primary site and is generated from the first serial digital data stream through a modulated direct digital synthesis thereof. A third circuit is used to convert the second serial digital data stream into an analog OFDM / DMT signal for transmission to the receiver of the primary site.

Provided are a method, system, and article of manufacture for mirroring data between a first site and a second site. Updates to segments of storage at the first site are copied to corresponding segments of storage at the second site. Codes are generated from the segments at the second site and a valid flag is provided for at least one code indicating whether the code for the segment of data is valid. One code is generated from each segment of storage at the first site. An operation is initiated to copy segments from the second site to the first site. A determination is made for segments at the second site as to whether the valid flag for the code for the segment at the second site indicates that the code is valid in response to initiating the copy operation. The valid code for at least one segment in the second site is compared with the code for the corresponding segment at the first site to determine whether to copy the data from the segment at the second site to the first site as part of the copy operation.

A computer system that has formerly handled a service is quickly reproduced with another computer system to resume the service immediately. The association relations between services run by a primary site (1) and primary site servers (13) are collected. The association relations between the primary site servers (13) and a primary site storage system (15) are collected. The association relation between the storage system (15) of the primary site (1) and a storage system (25) of a secondary site (2) is collected. The association relations between the primary site services and the primary site servers (13), the association relations between the primary site servers (13) and the primary site storage system (15), and the association relation between the primary site storage system (15) and the secondary site storage system (25) are copied as configuration information from the storage system (15) of the primary site (1) to the secondary site (2). On the secondary site (2), based on the copied configuration information of the primary site.(1), services of the primary site (1) are assigned to servers (23) of the secondary site (2), and the secondary site servers (23) to which the services are assigned are associated with the storage system (25) of the secondary site (2) to reproduce the primary site (1) on the secondary site (2).

A communications system where data blocks from a communications device are received at least in a serving site over a wireless interface. The serving site typically checks whether data blocks have been correctly received and sends acknowledgement information to the communications device accordingly. An assisting site may also receive the data blocks and send information indicating whether data blocks have been correctly received in the assisting site. In this case, the serving site may request erroneously received information from the assisting site. Alternatively, the assisting site may send information indicating erroneous reception of data blocks in response to noticing a data block sent by the communications device. As a further alternative, the assisting site may be synchronized with the data blocks sent by the communications device and send quality information relating to the wireless interface between the communications device and the assisting site to the serving site.

The present invention provides a storage system whereby it is also possible to back up the generational management information of a copy source disk array device. The disk array device of the primary site manages back-up data of a main volume, in a plurality of generations, by means of differential snapshots. The differential data of the main volume and the main pool is transferred from the primary site to the secondary site, at a prescribed timing. The secondary site holds the secondary volume, which is a copy of the main volume, and a secondary pool which is a copy of the main pool. The primary site also transfers the generational management information to the secondary site. The generational management information may also comprise a differential bitmap table and a withdrawal destination address management table. The secondary site holds a copy of the generational management information. Thereby, it is possible to back up the whole of the data, including the generational management information, and hence protection against failure is improved.

The invention provides an urban traffic system and method. The urban traffic system at least comprising an urban traffic management control center, an information nervous system, a rail station equipment system, an auxiliary station equipment system, a rail vehicle cluster, a passenger management system and a running guaranteeing system is established in a city firstly. By the adoption of the urban traffic system, rail trains capable of running directly to a destination from a departure place are automatically grouped through the system for passengers with the same departure place, the same destination and the same get-on time point according to taking applications sent by the passengers in advance. Trains for passengers with different time, different departure places and different destinations are under the unified real-time control of the urban traffic management control center to designedly, cooperatively, accurately and efficiently run on the optimal running routes planned through a computer, the purpose that each passenger directly reaches the destination from the departure place is achieved, the highest carrying efficiency is achieved as well, and the purpose of the urban traffic system is achieved. The urban traffic system can be used as a main carrying means for urban traffic to be widely applied to construction of each city.

A system is provided for storage of journal data from a primary site to a secondary site with a predefined quality of service. In one implementation, the primary storage system stores information for updating data stored on the primary disk array in the form of a history of updates made to the data. The primary storage system is configured to transfer this journal information to the secondary storage system. The user can specify the quality of service desired using a variety of measures, for example, a recovery point objective or a recovery time objective. In response, a copy manager within one of the storage systems determines the capacity of the various primary and secondary volumes, and determines the copy rate available, typically dependent upon the bandwidth between the primary and secondary systems. The copy manager then copies journal data to the remote site where it is stored.

Provided are a method, system, and article of manufacture for controlling a first storage system receiving commands from a first and second managers to create a consistency group with a second storage system. Host writes are received at the first storage system, wherein the first storage system includes a first storage system primary site and a first storage system secondary site. The first storage system sends the host writes from the first storage system primary site to the first storage system secondary site. Host write operations are quiesced at the first storage system in response to a first command from a first manager. Host write operations are resumed at the first storage system in response to receiving a second command from the first manager. The first storage system receives a run command with a marker, wherein the marker indicates a cycle number to control the cycles of the first and second storage systems. The first storage system sends the marker from the first storage system primary site to the first storage system secondary site. The first storage system sends the marker to a second manager. The first storage system applies the host writes to the first storage system secondary site. The first storage system sends a first message to the first storage system primary site from the first storage system secondary site after completing the applying of the host writes. The first storage system sends a second message to the first manager indicating whether conformation was received from the first storage system secondary site that the host writes were applied.

A method for using a reference volume for initial synchronization of a replicated volume group. The method includes initiating a replication and synchronization operation between a parent virtual machine and a child virtual machine, and specifying a parent virtual machine to be used for replication and a subsequent synchronization. The method further includes accessing a point in time snapshot of the parent virtual machine, coordinating with a secondary site to obtain an image of the parent reference volume at said point in time, and copying the common regions from a parent reference volume to a new volume. The differences between the parent reference volume and the new volume are transmitted and are applied to the new volume to synchronize the child virtual machine on the secondary site to the child virtual machine on the primary site, wherein the child and the parent may be in different virtual machine groups.