Hello!

The clue is in the name of the parameters. they are 'proxy_CACHE_bypass' and 'proxy_no_CACHE'. I.E. They have to do with the nginx CACHE not bypassing nginx.

In your question, you have a client connected to an Nginx Proxy. There is no connection between them and the back end. Therefore, the back end cannot serve them anything directly.

If you want to serve directly from the back end, then you need to redirect the client to the back end so that they can connect to the back end.

Whatever they are connected to is what can and will serve the request.