Is it possible to use keep-alive without upstream?

Question

System administration

Now I am developing a control panel for reverse proxy. The proxy is implemented on nginx.
I want to implement DNS so that the user himself can change the backend IP at any time, but I would also like nginx to keep an open connection with it and not close it, as it happens if you just specify ip in proxy_pass
Accordingly, upstream is not suitable for such a task.

Are there any options for implementing this idea?

Answer 1

If you allow the user to change the list of backends - why not just synchronize it with the list of upstreams in the nginx config?