The current status of the OPC UA server is displayed in the Diagnostics tab. You will also see a list of connected OPC UA clients and subscriptions there.

For each connection, the name and ID of the session are displayed along with the time stamp of the most recent communication.

For each subscription, the subscription ID, the number of monitored tags, the publication interval and the next sequence number are displayed. The latter value is increased each time new data is sent for a particular subscription.

If you select an OPC UA client in the upper list, the subscriptions are filtered so that only subscriptions that are relevant for this client are displayed in the lower list.