In the TIA Portal you have to enable “Operate as OPC Server” in the Runtime Settings of your project. Download and restart the runtime, and then the OPC UA Server is listening on opc.tcp://localhost:4890.
You need to have a user which has a role with the OPC-UA read and write access permission.
When you try to connect with a client the client will send the certificate to the server and typically the certificate is rejected by the server. To trust the certificate you have to move the certificate from the “Rejected” folder to the “Trusted” folder.
Add a label object into your screen and add some lines of code to get a QR image. In this example a mobile phone app will scan the QR code and send username and password via a GraphQL server to WinCC OA and set it on datapoints (username and password should additionally be encrypted).
Lot of times my ssh session get broken because I didn’t do anything for a while. Sometimes I have started “top” just that the connection does not get broken because of inactivity. But this is not really what I wanna do everytime. Luckily the SSH client can be configured to send alive telegrams for every session so that you do not need to pass arguments every time you open a SSH conneciton.
Following settings will make the SSH client to send alive telegrams to the other side every 60 seconds, and give up if it doesn’t receive any response after 2 tries.