About the Join process

Figure 9 below shows the basic process steps in a Join performed from the Supervisor station.

Figure 9. Join process steps when Join is issued from Supervisor station.

As shown in this diagram, once connected, the Supervisor finds the JoinProfile on the subordinate and opens its station “profile.bog file”. The Supervisor then merges the profile.bog file (and/or individual “Station Slot Paths” in export tags) with the current NiagaraStation structure. Then the Supervisor finds all enabled export tags on the subordinate, and performs the join, merging with existing components under the NiagaraStation.

The Supervisor then disconnects. Details about the Supervisor Join are in its local job log.

Note Starting in AX-3.7, “Fox SSL” may be used in connections between the JACE stations and the Supervisor, depending on configuration. In this case, note that initial Join attempts may fail due to “non-approved certificate host name validation”. If so, you will see the appropriate errors in a Join’s job log. You must manually approve certificates between the client and server before Joins can succeed. Typically you do this from the “Allowed Hosts” tab of the “Certificate Management” view (on platform service: CertManagerService) in the stations. For complete details on AX-3.7 and later SSL, refer to the NiagaraAX SSL Connectivity Guide.

Join process from subordinate

If the Join is issued from the subordinate station, the same process steps occur as shown in Figure 9, plus an extra, initial connection step from the subordinate to the Supervisor, as shown in Figure 10.

Figure 10. Extra initial connection in processes for Join issued from subordinate station

Note that this method allows a new subordinate to be added to the NiagaraNetwork of the Supervisor even in cases where the Supervisor is “unaware” of the remote host, providing the subordinate station’s NiagaraNetwork has a NiagaraStation node representing the Supervisor, complete with configured Fox client connection.

In this scenario the subordinate’s JoinProfile would require valid entries for “Default Subordinate User” (typically a service account for station to station communications with full, admin-level, permissions,) “Default Subordinate User Password”, “Default Subordinate IP Address”, and possibly “Default Subordinate Port” properties. For further details, see Editing the Join Profile.