Test buffering

Buffering of data occurs on the interface nodes while Data Archive is being moved. Buffering processes include PI Buffer Subsystem (pibufss) or API Buffer Server (bufserv).

Some interface nodes can recover historical data from their data sources and require neither pibufss nor bufserv. See documentation specific to each interface to determine if an interface requires buffering.

If the interface node uses buffering, verify that the buffering process is working properly. For more information on testing buffering, see the Knowledge Base article: KB00300 - How do I simulate a PI Server shutdown to test buffering. Follow these steps to verify buffering:

1. Disconnect the interface node from the network for a few minutes.

2. Reconnect it.

3. When the node is reconnected to the network:

   • The interface should historically recover data from its data source and you should see a continuous sequence of values in the application you use to view Data Archive data, such as PI ProcessBook or PI SMT. The recovered data will look like there has been a normal continuous flow of data during the time of the disconnection. For example, you can use PI Archive Editor in PI SMT to check that data for a frequently archiving tag is continuous.

   • Actual data should be passed through the buffer and be sent right-away to Data Archive, so that you should see a continuous flow of data in the application you use to view Data Archive data.