Configuration adjustment for GRPC service

[Ľuboš Pinteš]

Hello, everybody,
I am implementing a GRPC service which has methods, i.e. request/reply 
and one streaming method, through which the server sends events at 
random intervals.
The GRPC server is written in Go, the client in C#, we are using Grpc.Core.

If the server is not running and I call one of the request/reply 
methods, an error occurs as I expect. But if I call the streaming 
method, Nginx accepts the connection and the client gets stuck on 
calling await events.ResponseStream.MoveNext(...);

I would like to ask how to configure Nginx so that an error occurs even 
if the streaming method is called if the server is not running, e.g. it 
restarts out of my control if the server on which my service is running 
restarts.

Thank you