Learn about allowlist file configurations

For enhanced security, create an allowlist of output points and enable the allowlist startup parameter for the interface. When this feature is enabled, the interface verifies that an output point is in the allowlist before writing to an OPC data source.

The allowlist file is a comma-separated values (.csv) file that contains a list of approved output PI points and the attributes that associate the PI point with a writable value in an OPC device.

For this interface, include the following required attributes in the allowlist file to secure the output points:

• tag

• instrumenttag

• location3

• userint1

The allowlist feature also supports range checking of output values. Include the zero and span attributes to specify a secure range of values to send to the OPC data source. These attributes specify the minimum (zero) and maximum (sum of zero and span) allowed for the output value.

For additional information on creating and configuring and enabling an output point allowlist file, see the PI Universal Interface (UniInt) User Guide.