How to simulate tcp connection loss on localhost

Question

I have a ASP NET Core web api that uses websockets. I am trying to find out if the server handles internet connection loss (client side) correctly.

However since I have only one machine on which both the server and the client run, i know that localhost does not use the Network Interface, and the desired handler is not triggered when I cut off the internet.

How can I thus have a server that runs a localhost, and a client that also runs on localhost but uses the network interface, so that I can cut the internet off and see how the server behaves for the given client?

Answer 1

I useTCPView to do this sort of testing. You can find the connection in the list, then right-click/close it: