SteelEye™Data Replication (SDR) is a solution that provides dynamic, disk-level replication of data across local and wide area networks.
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SDR allows synchronous and asynchronous mirroring of data. During synchronous mirroring writing process is finished if all data are stored local and remote. During asynchronous mirroring writing process is finished if data are stored local and in a queue connected to the mirror.
After a network failure or failover a partial resynchronisation is done. That means only changes are resynchronized. With asynchronous mirroring concepts are possible where server systems are remote.