Exam Professional Cloud Developer topic 1 question 211 discussion

https://cloud.google.com/architecture/best-practices-for-running-cost-effective-kubernetes-applications-on-gke#make_sure_your_applications_are_shutting_down_in_accordance_with_kubernetes_expectations

"Most programs don't stop accepting requests right away. However, if you're using third-party code or are managing a system that you don't have control over, such as nginx, the preStop hook is a good option for triggering a graceful shutdown without modifying the application. One common strategy is to execute, in the preStop hook, a sleep of a few seconds to postpone the SIGTERM. This gives Kubernetes extra time to finish the Pod deletion process, and reduces connection errors on the client side." https://cloud.google.com/architecture/best-practices-for-running-cost-effective-kubernetes-applications-on-gke#:~:text=If%20your%20application%20doesn%27t%20follow%20the%20preceding%20practice%2C%20use%20the%20preStop%20hook https://kubernetes.io/docs/concepts/containers/container-lifecycle-hooks/#container-hooks

I go with B, that is liveness probe and if failed for max retries then call prestop hook to gracefully shutdown the container. D is also very close, but it used init container to check for the database connectivity first. I am not sure whether we can prestop hook if initContainer fails to starts.

https://cloud.google.com/architecture/best-practices-for-running-cost-effective-kubernetes-applications-on-gke#make_sure_your_applications_are_shutting_down_in_accordance_with_kubernetes_expectations -> the preStop hook is a good option for triggering a graceful shutdown without modifying the application. https://kubernetes.io/docs/concepts/containers/container-lifecycle-hooks/#hook-details -> This hook is called immediately before a container is terminated due to an API request or management event such as a liveness/startup probe failure, preemption, resource contention and others. A call to the PreStop hook fails if the container is already in a terminated or completed state and the hook must complete before the TERM signal to stop the container can be sent. The Pod's termination grace period countdown begins before the PreStop hook is executed, so regardless of the outcome of the handler, the container will eventually terminate within the Pod's termination grace period. No parameters are passed to the handler.

Answer B

B is the answer.

D could be the right answer