OPC server-level failover

To ensure that data continues to flow from the OPC server to PI Interface for OPC DA, the interface can be configured to switch to another OPC server under the following conditions:

• Loss of connectivity to current OPC server

• The OPC server state changes to a value other than "RUNNING"

• Specified OPC server items indicate that the OPC server is unavailable, either by a specific value or by the quality

OPC servers can be fully redundant (multiple servers active at the same time) or configured for failover, where one server at a time is active. Note that OPC servers vary widely in their approach to tracking and reporting status, so consult your OPC server documentation to determine what options are supported.

The following diagram illustrates a basic OPC server-level failover configuration.