healthz is now deprecated. Instead use
/livez endpoint is an endpoint that you can add to your application that Kubernetes will periodically call to check that the application is healthy and responding to requests.
It simply returns a 200 OK status.
/readyz endpoint is an endpoint in your application that Kubernetes will call when a pod is starting so that it can determine when your application is ready to start accepting traffic.
This is useful in the instance when the pod has started, but your application within the pod is not ready to accept incoming requests yet – maybe it takes a while to launch and needs to do some config etc.
So Kubernetes will keep pinging this endpoint and once the application is ready, the
readyz endpoint will respond with a 200 OK and Kubernetes will know the application is ready to start receiving traffic.
From that point onwards it will then use the
livez endpoint to perform the periodic health checks.