Why I can't write boolean to PLC with OPC UA one computer OK the other computer NOK

General
1

I installed NODE-RED on two computers at the same time. One computer with WINDOWS 10 and the other computer with WINDOWS 11. I created FLOW on a computer with WINDOWS 10 and writing to the PLC with the OPC UA server works for me there. It does not work on a computer with WINDOWS 11. I tried turning off the firewall and still not working. Reading from OPC UA works but writing does not. I don't know what else I could try. Has anyone encountered this? I will ask for advice on what I could try. Thank you

SnĂ­mka obrazovky 2024-09-23 090717
SnĂ­mka obrazovky 2024-09-23 0907171198Ă—170 12.7 KB

2

I came to something like this. Has anyone encountered this security flag before? :

The error message you encountered is related to the recent security issue CVE-2023-46809, which affects the use of RSA PKCS#1 v1.5 in Node.js. This issue emerged in the context of certificate validation and security in OPC UA communication.

Your OPC UA client in Node-RED is likely using RSA PKCS#1 v1.5 for encryption or verification, which is causing this issue. The latest versions of Node.js have tightened security measures for this type of encryption, which may be preventing the write operation to the OPC UA server.

How to resolve the problem

  1. Use the --security-revert=CVE-2023-46809 flag:
  • This will enable backward compatibility with RSA PKCS#1 v1.5 and temporarily disable the security measures introduced in Node.js.
  • Run Node-RED with this flag from the command line:

bash

node --security-revert=CVE-2023-46809 /path/to/node-red
  • If you use the standard command to start Node-RED (node-red), try the following:

bash

node --security-revert=CVE-2023-46809 /usr/local/bin/node-red
  1. Permanent flag setting:
  • If you want to make this setting permanent, you can adjust the startup script for Node-RED or create a command alias.
  1. Update Node.js or the OPC UA package:
  • Check for updates to the Node-RED OPC UA package or Node.js that address this issue without the need for the flag.
  • You can update Node.js or the OPC UA package using the command:

bash

npm install -g node-red-contrib-opcua
1 Like
3

I uninstalled version 20 and installed version 18. No change. Firewall and antivirus turned off on the PC. Still NOK. I tried replacing settings node-red from a working PC and still NOK. I made a simple flow change by moving the node - still NOK. Later I went back to work and the write is working. What helped? I have no idea. Now writing variable to PLC works... Done :upside_down_face: