Hi,

Unfortunately at the moment: no.

Technically some day in the future it could do the HistoryRead to the source servers, but I cannot say when or if that happens. Please contact sales@prosysopc.com if you would need this. Also I should note it is also a bit ambiguous how the data from the source server should be interpreted in a case like this, because the data is collected via MonitoredItems that do sample, thus the data obtained by Historian might not be 1:1 the data read via HistoryRead from the source (e.g. should it be “sampled” as well?). And then also should Historian query the history from before it was added as a source server? For example, in the case of our SimulationServer, that is infinite, as it just simulates the history values for any timeperiod. In a real case it could still be more than what the database can handle (e.g. disk size limitations).

As to querying the data manually, that is a bit harder. Most likely that cannot be made, not at least with normal OPC UA HistoryRead for nodes the Historian is collecting data, because the call would be ambiguous for local vs. source. Some non-standard way for this could probably be doable e.g. via a Method, but not sure if desirable.

Technically also the application’s use-case at least originally was to also enhance them by adding history. If the servers already support HistoryRead, https://www.prosysopc.com/products/opc-ua-gateway/ would do better as it is pure aggregation and wont suffer the same ambiguity.