...It needs to be open on the right port. 5001 is the default and is used in the examples below, but it can be set to whatever you need. In a web browser IPFS HTTP client (either browserified or CDN-based) might encounter an error saying that the origin is not allowed. This would be a CORS ("Cross Origin Resource Sharing") failure: IPFS servers are designed to reject requests from unknown domains by default. You can whitelist the domain that you are calling from by changing your ipfs config.