The OPCUA client driver continues to send a publish request for a subscription even though the OPCUA server reports that the subscription is no longer valid.

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• The OPCUA client driver should increase the grace period to establish if a server is no longer responding

  Summary If under specific circumstances an OPCUA server is not capable of sending a publish response with a keep alive message in time the OPCUA client may assume that the OPCUA server is no longer available. A grace period is applied of 1000ms. ...

• The OPCUA client driver may cause the runtime to stop responding under specific circumstances

  Summary The OPCUA client driver uses the due time for publish responses (keepalive) to check if the OPCUA server is still responding. Normally if the connection to the OPCUA server is lost, the connection is closed at the TCP level. If however no ...

• The OPCUA client driver stops sending service requests for a subscription when no variables are needed in the runtime and attempts to reuse the no longer existing subscription when a variable is needed again.

  Summary When momentarily no variables are used in the runtime from a connection in the OPCUA client driver, the OPCUA client driver no longer sends service requests for the subscribtion that was previously created for these variables. The OPCUA ...

• The OPCUA client driver sets variables INVALID in the runtime after 20 seconds with specific settings for publishing interval and MaxKeepAliveCount and no value changes in the OPCUA server.

  Summary When the OPCUA client driver uses settings with a publishing interval and a MaxKeepAliveCount that result in a value of more than 20 seconds, and the OPCUA server sends no value changes (publish responses) for all the variables in the ...

• Variables from the OPCUA client driver that have a bad statuscode on startup will never get a value.

  Summary If the value of a OPC UA variable has a bad status code when OPCUA client driver starts, the variable will never get a valid value in the runtime, even when variable gets a good statuscode in the OPCUA server. Description If the value of a ...