Storage Replica can be used to enable replication between two servers; between two clusters; inside a stretch cluster to synchronize the nodes inside the cluster; and "server to self" to copy data from one volume to another volume inside the same server.
One use case for Storage Replica is disaster avoidance, where services and data can be moved to another site before a hurricane hits and disrupts those services.
For synchronous replication, the round-trip latency must be equal or less than 5 milliseconds and there must be a minimum of a 1 Gbps connection between servers.
For longer distances, Storage Replica can use asynchronous replication when copying data from cluster to cluster and from server to server.
Storage Replica is not meant to back up individual files because files that are deleted at the source will also get deleted at the destination.
Microsoft Storage Replica requires an Active Directory domain to function and needs to run on the Datacenter edition of Windows Server 2016.