Free source is every where on the internet especially for Linux system. Today, I wants to share how to run MongoDB on Raspberry Pi 3 and then use Node Red to get data and send data back to the database we just created. By doing this, you can just spend little money on Raspberry Pi 3 hardware and then you could start your way to build a data collection site with the latest flow-based programming tool, Node Red. Prepare 1. Refer to the detail and great instruction already post by http://recipes.item.ntnu.no/using-node-red-mongodb-to-gather-and-publish-data-on-a-raspberry-pi/ 2. Use SSH to log in Raspberry Pi 3 and start Node Red 3. Enter URL to Node Red at port 1880 and start draw the flow MonogoDB 1. Drag MongoDB block and Assign the Server IP address and DB name 2. Assign the Collection and Define operation as "Insert" 3. After Deploy, Go to Node Red UI and Test the switch function 4. Use SSH command to enter mongoDB shell and "use myDB"