A passive routing session is opened on one system only.
If more than one system is specified in the passive routing rule, a system is chosen based on Least Used (LU), Round Robin (RR), Weighted Round Robin (WRR), or first available. If RR is specified, the session open is attempted on the first session in the list of systems associated with the rule.
When running a load utility that opens multiple data sessions, only a routing rule that directs those sessions to a single system is allowed. Routing rules that load balance sessions across multiple systems are not allowed, because they would attempt to connect and load data across those specified systems. If you run a load job using a LU, RR, or WRR PASSIVE routing rule with multiple systems, it is rejected with an error.