I was wondering what people would consider is the easiest way of setting up a connection between a raspberry pi 3 model b and an ignition instance on a different device on the same network. I don't want to buy extra hardware, so I was wondering which type of connection most people would use, and if there were any resources you recommend.
The two sensors are a temperature sensor in one wire and a water level sensor in i2c.
Well... the easiest thing might be to use the WebDev module to expose endpoints on the Ignition side, then periodically make HTTP POST requests to those endpoints with the sensor data. In the endpoint logic you can write it into memory tags.
If you have used Node-red to read the sensor data there is an ignition node, There is also a module for ignition to read node-red too. You could also set node-red as OPC server. Never used any of these methods, only MQTT. Which would mean you have to buy the module unless this is for Maker.