If a backend server crashes while handling a response, what does the client see? The specific case I'm thinking of is when an API call causes X server to crash. So API call from outside hits the F5, F5 passes the call along to X server, X server crashes before sending a response back to the F5. Does the F5 just drop the connection (TCP RST), or does it send a valid HTTP response with like status code 500?
@Juergen_Mang's answer is a possible action, but not the only possibility. What happens is dependent on how your action on service down in your pool is configured. Read Deb's article here for details.