The following rules apply to dual-string configurations that use mediators.
Disk sets must be configured with exactly two mediator hosts. Those two mediator hosts must be the same two cluster nodes that are used for the disk set.
A disk set cannot have more than two mediator hosts.
Mediators cannot be configured for disk sets that do not meet the two-string and two-host criteria.
These rules do not require that the entire cluster must have exactly two nodes. Rather, only those disk sets that have two disk strings must be connected to exactly two nodes. An N+1 cluster and many other topologies are permitted under these rules.