Health checks in ASP.NET Core

I am using Health checks in ASP.NET Core
Health checks in ASP.NET Core | Microsoft Learn

Is there anything I could read from NServicebus (RMQ transport) which indicates health?

Not directly, we do emit log entries that could be used to monitor the state of the endpoint. Also, important metrics could be captured and used for a state machine that is relevant for your environment.

Additionally, I recommend converting a critical error callback into a health check if your callback will not automatically tear down an endpoint instance:

This could be used to have your own custom health check that can be used for ASP.NET health checks

– Ramon

I have implemented OnCriticalError, but it doesn’t seems to be fired when using SendOnly endpoints right? I have shut down my RabbitMQ, but nothing happens.

A build in Ping definition that would be ignored (by NSB) in the other end would be nice. Just to test if the transport is up and running. I know I could create my own, but then I have to coordinate with the other end(s) to ignore it.

That is correct, critical errors would be about the NServiceBus message processing perspective where the transport or persistence is not working as expected.

Transport are considered to be highly reliable and critical infrastructure. Such infrastructure shouldn’t be monitored from all individual endpoint instances but for example directly from somewhere else.

Can you share details on why you want to monitor this from a send-only endpoint? I could capture this and create an feature request for it. You could also create an issue yourself if you prefer that at