Bidirectional ObjectServer Gateways

The bidirectional ObjectServer Gateway enables alerts to flow in both directions between two ObjectServers. You can use bidirectional gateways to create a failover pair of ObjectServers. The executable file name of a bidirectional ObjectServer gateway is nco_g_objserv_bi.

Changes in one ObjectServer are replicated in the other ObjectServer. This replication ensures that both ObjectServers contain the same alerts and allows you to maintain a backup ObjectServer.

Important: Ensure that table data is changed in only one of the ObjectServers. If table data is changed in both ObjectServers, the gateway might not be able to reconcile the changes and the row data might be left in an indeterminate state. The configuration setup for a failover pair of ObjectServers ensures that only data in the primary ObjectServer is changed, except when the system fails over to the backup ObjectServer.

Information flow

The following figure shows the structure of a bidirectional ObjectServer Gateway.

Figure 1. Bidirectional ObjectServer Gateway 
Conceptual diagram of the Bidirectional ObjectServer Gateway  showing the interaction between two ObjectServers

The bidirectional gateway consists of a mapper and two reader/writer components (one for each ObjectServer). The flow of information between the components is as follows:

  •  1 : The reader reads data from one ObjectServer.
  •  2 : The data is passed to the gateway mapper.
  •  3 : The mapper transforms the data into a format that is appropriate for the second ObjectServer. To transform the data, the mapper uses the settings in the map definition file.
  •  4 : The mapper passes the data to the reader.
  •  5 : The writer writes the data to the second ObjectServer.