OceanStor Dorado can support multiple types of 3DC solution, which is the core of the Geo-Redundant Solution that ensures service continuity and data reliability in case of disasters. The 3DC solution consists of a production center, an intra-city DR center, and a remote DR center. The supported 3DC topologies are parallel, serial, and star. In parallel topology, both the production center and the intra-city DR center form remote replication relationships with the remote DR center. In serial topology, the production center forms a remote replication relationship with the intra-city DR center, which in turn forms another remote replication relationship with the remote DR center. In star topology, the production center forms a HyperMetro relationship with the intra-city DR center, and both of them form remote replication relationships with the remote DR center.