OPC-UA Client Publish Before CreateSession or ActivateSession

I’m seeing what I think is an issue with the OPC-UA Client in version 8.0.14 (b2020062220). The problem occurs after the server to which the client is subscribed goes offline and then returns. The client opens a new connection and completes an OpenSecureChannelRequest exchange, but then immediately sends a PublishRequest on that channel without having yet performed a CreateSession or ActivateSession. The standard says at that the “[ActivateSession] request shall be issued by the Client before it issues any Service request other than CloseSession after CreateSession. Failure to do so shall cause the Server to close the Session.” The server does this, but then the whole process repeats yet again, without a stable connection ever being re-established. I have a PCAP that shows the traffic, but can’t upload it since I’m apparently I’m too new. Let me know how to get it to you.

Can you capture this on Wireshark and upload it please?

You’ll have to make sure the connection between client and server is not encrypted (SecurityPolicy = None).

edit: derp, should have finished reading. Email the capture to kevin@inductiveautomation.com

If you can’t email the capture for some reason let me know and I’ll create a Dropbox target to upload them to.