Data egress

Edge Data Store (EDS) provides an egress mechanism to transfer data through Open Message Format (OMF) to CONNECT data services or a PI Server. For each egress destination, you need to prepare the destination and configure an endpoint.

Prepare egress destinations to ensure that CONNECT data services or PI Server are properly configured to receive OMF messages and record information needed to create a connection to the destination.

Configure an egress endpoint to specify the connection information for a destination and the details of the data transfer. Each endpoint is independent of all other egress endpoints, and more than one endpoint for the same destination is allowed.

Note: Only streams with a single, timeseries-based index can be egressed. For more information, see Egress execution details.

EDS allows the following types of egress:

• Periodic egress - Once configured, periodic egress runs at regularly scheduled intervals.

• Manual egress - Manual egress is configured and run on an as needed basis.

Periodic egress ensures that all the data EDS collects is sent to permanent storage on a regular basis. Manual egress gives you the flexibility to retrieve data whenever you need it.

For instance, suppose you have EDS set up to gather data from a wind turbine. You schedule periodic egress to transmit data to CONNECT data services every Friday at noon. A severe storm affects the wind turbine's location over the weekend, and you prefer not to wait until Friday afternoon to assess the turbine's performance during the storm. Therefore, you initiate a manual egress request to EDS to send the weekend's data to CONNECT data services, enabling you to begin data analysis immediately.

Note: AVEVA PI Server is also supported as an egress destination. The setup process is similar to CONNECT data services.

Kerberos

Kerberos is the only authentication mechanism that is enabled by default in PI Web API. Kerberos provides per-user security that is native to Windows and Active Directory, and that is well supported in Microsoft clients. Kerberos does not rely on credentials being transmitted across the wire, which makes it ideal for use with untrusted connections.

Use of Kerberos authentication requires the correct configuration of Active Directory delegation for the account hosting the PI Web API service in Active Directory. Correctly configured delegation requires that an Active Directory Domain Administrator grant delegation privileges to the account hosting PI Web API (or in the case of the default virtual service account, to the computer account of the computer hosting PI Web API). Correctly configured delegation also requires that Service Principal Names be correctly set on the account hosting.

Refer to Commonly encountered problems in the PI Web API guide for detailed steps for resolving issues related to Kerberos delegation.