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.