Abstract: Storing recovery data for a data center includes providing synchronous data from the data center to a local destination, providing chunks of data from the local destination to a first remote destination, different from the first remote destination, and providing chunks of data from the data center to a second remote destination. At least some of the destinations may maintain a plurality of maps, where each of the maps associates synchronous data being provided to the local destination with a specific chunk of data. In response to receiving an indicator in connection with creation of a new chunk of data, the at least some of the destinations that maintain a plurality of maps may point to a new map. There may be two maps or more than two maps.

Abstract: Toggling between a first storage configuration and a second storage configuration includes disabling asynchronous data transfer to a third storage group from one of the first storage group and the second storage group and enabling asynchronous data transfer to the third storage group from an other one of the first storage group and second storage group. Toggling between a first storage configuration and a second storage configuration may also include, prior to disabling asynchronous data transfer to the third storage group, transferring pending data to the third storage group. Toggling between a first storage configuration and a second storage configuration may also include, after enabling asynchronous data transfer to the third storage group, transferring data to the third storage group that had been pending prior to disabling asynchronous data transfer to the third storage group.

Abstract: Described are techniques used in performing data replication processing. Data is replicated on a recovery site from a production site. When a disaster occurs, the state of the replication processing is determined and a restart copy of the data is made available from the recover site. Processing continues based on whether protection mode is desired such that the system executes using the recovery site as the restart with a replicated copy of the data. Data is propagated from the recovery site to the production site to resume operations and replication processing originating from the production site.

Abstract: Described are techniques used in performing data replication processing. Data is replicated on a recovery site from a production site. When a disaster occurs, the state of the replication processing is determined and a restart copy of the data is made available from the recover site. Processing continues based on whether protection mode is desired such that the system executes using the recovery site as the restart with a replicated copy of the data. Data is propagated from the recovery site to the production site to resume operations and replication processing originating from the production site.

Abstract: A data-mirroring method in which, while an I/O process is processing a first I/O request for writing data to a first device, control is obtained from that I/O process executing on a host computer. A second I/O request, this one for writing the data to the second device, is then created. Then, control is returned to the I/O process by causing the first I/O request to be made available to a first data storage system managing the first device.

Abstract: Described are techniques used in performing data replication processing. Data is replicated on a recovery site from a production site. When a disaster occurs, the state of the replication processing is determined and a restart copy of the data is made available from the recover site. Processing continues based on whether protection mode is desired such that the system executes using the recovery site as the restart with a replicated copy of the data. Data is propagated from the recovery site to the production site to resume operations and replication processing originating from the production site.

Abstract: Described are techniques used in performing data replication processing. Data is replicated on a recovery site from a production site. When a disaster occurs, the state of the replication processing is determined and a restart copy of the data is made available from the recover site. Processing continues based on whether protection mode is desired such that the system executes using the recovery site as the restart with a replicated copy of the data. Data is propagated from the recovery site to the production site to resume operations and replication processing originating from the production site.

Abstract: An apparatus for providing a uniform application of a functional coating to one or both sides of a moving metal strip includes an enclosed cabinet in which a corona discharge field is established between high voltage electrodes and the strip. The coating liquid and air are separately supplied under pressure to atomizing nozzles within the enclosure. The nozzles create a dense flat spray that is directed into the discharge field at an acute angle relative to the strip. The particles in the spray become charged and are attracted to the grounded strip, while those that are not charged are directed onto the strip by the force of the discharge field. The rate at which the coating liquid is supplied to the nozzles is varied in accordance with the speed of the strip to thereby obtain a uniform coating regardless of variations in strip speed or width.