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Can't connect to plcnext's OPC UA server via private key in UA Expert

I need to connect to my OPC server on PLCNext AXC F 2152. I can do it with credentials but when i use certificate and private key - UA Expert sends me: "Error 'BadConfigurationError' was returned during ActivateSession".

I got the certificate and private key from PLCNext Controller via SSH in folder /opt/plcnext/Security/IdentityStores/OPC UA-self-signed. I didnt found any documentation where i can find private key else. I also validate them using:

"openssl x509 -noout -modulus -in certificate.pem | openssl md5" - for certificate

"openssl rsa -noout -modulus -in key.pem | openssl md5" - for private key

the output value was the same

In OPC settings of my project i have set "Certificate" field to Self-signed by controller and download the project to plc. I also added some ip-addresses to avoid "BadCertificateHostNameInvalid" error

Finally i convert certificate.pem to certificate.der using online tools and then trying to connect to opc server using UA Expert:

When i connect i get:

After "Continue" i get no errors to ignore but in logs it sends me this:


Comments

  • Currently the OPC UA server only supports the "Username/Password" authentication method, or "Anonymous" (if security is completely disabled in the PLC - which is not recommended).

    There are plans to allow Certificate-based authentication in the future, but there is currently no timeline for this.

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