Open bbmmcodegirl opened 4 months ago
Hi @bbmmcodegirl, this seems difficult to track down. Does it always take a few weeks until the issue occurs and is it only a specific variable node that is missing data or rather random?
Hey! I am getting a similar issue on my end. Usually for me its the same nodes I have the following specifcations: OPC UA Client: Workstation.UaClient 3.11 Server: Basic OPC Server
I am getting the notifications for all other monitored items except a couple specific ones from time to time. Not too sure what is happening
@mregen sorry for the late answer. It turns out that yes, it seems to usually be a notification for one particular node value that gets missed at these very irregular intervals. But that is probably due to the fact that this one node is the one that changes most often. It gets many more changes than all other nodes. It is the value that changes in 42% of all of the notifications we receive.
Type of issue
Current Behavior
We are using this OPC/UA implementation inside a process within a production environment. Very rarely, we observe the Notification event for a
MonitoredItem
not being called, even though its value changed. This causes our production process to pause, so it is quite crucial for us. This is intermittent. We may receive 20 notifications for value changes, but then one of the notifications is missing, so we miss out on the change of that value. We currently use version 1.4.371.91 of the package, but this has also been observed with previous versions. The occurrence is very rare, so it is very hard to establish what the specific conditions are that make this occur. Note that when we had it occur, the value in the OPC/UA server was correct, as verified with a different tool. Only theNotification
event of the associatedMonitoredItem
was not raised when the value had changed.Expected Behavior
Our
<OnNotification>
event handler should be called whenever the value of the monitored item changes.Steps To Reproduce
Here is the code that we are using to subscribe.
The steps we currently use are:
Environment
Anything else?
No response