Node-red-contrib-opcua: "OPC UA Client" sometimes fails to reconnect

Hi everybody.

I use node-red-contrib-opcua (Version 0.2.284) to connect Node-RED with my WinCC OPC-UA Server (Version 7.5.2).
I have multiple instances of the "OPC UA Client" node.
Each of them subscribes to 7-13 variables.

Occasionally, after the connection to the OPC-UA server breaks, some of the "OPC UA Client"-Nodes are not able to reconnect to the server.
The reasons for the connection abort can be various. For example a network problem or the OPC UA Server is restarted.
The status of the node in this case is "reconnect re-established", but it won’t receive any more updates until we manually restart the Node-RED flow.

It seems like the client tries to reactivate the lost connection instead of creating a new one and in some cases, this doesn't work.

Does anyone have the same issue or a solution to fix this?

If we can't fix this problem otherwise, our last solution is a monitoring flow that automatically restarts the flows when an "OPC-UA Client" node provides the status "reconnect re-established".

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It can be also that the server is out of resources as they limit sessions or variables sometimes.
In case of network break old sessions are not cleaned immediately thus server can "douple" sessions for a short moment and this can cause state node-red client cannot reconnect.
You can reduce sessions by using less client nodes (reference and msg.action at input msg).

Could be also fix in the latest node-opcua: Releases · node-opcua/node-opcua · GitHub

hello, I have similar problem. Each time that my server reboot, the only way i found to reestablish the subscribe is to restart Flow in Nodered interface.
What is a bit tricky is that the OPC UA connection is working for some nodes and not for others.
For example, some read and some write could work. The browse commande also give the good results but the subscribe does not restart and retriggering the subscribe with the variable definition is refused (giving error message).
How to triger same reset action on the node as restart flow automatically when it occurs?
I was running OPC_UA version 0.2.91 and now updated to 0.2.287 to see if it works better...
Thanks for any help

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after updating to 0.2.287, OPC_UA is not working at all... I get invalid endpoint error message.
I did not change anything except the OPC_UA update...I am not happy... In fact i discovered that the last version was not compatible with My Nodered version (1.2.6) so i need probably to update nodered first before to update the nodes. Downgrading the opcUA node to the old version using npm did not work,
The only solution that work was to restart from the yesterday backup of my IOTstack.

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