Answers

Here are the answers to this chapter’s questions:

1. Assuming we have a Docker image in a registry for the two application services – the web API and MongoDB – we need to do the following:
   1. Define a deployment for MongoDB using a StatefulSet object; let’s call this deployment db-deployment. The StatefulSet object should have one replica (replicating MongoDB is a bit more involved and is outside the scope of this book).
   2. Define a Kubernetes service called db of the ClusterIP type for db-deployment.
   3. Define a deployment for the web API; let’s call it web-deployment.
   4. Let’s scale this service to three instances.
   5. Define a Kubernetes service called api of the NodePort type for web-deployment.
   6. If we are using secrets, then define those secrets directly in the cluster using kubectl.
   7. Deploy the application using kubectl.
2. Liveness and readiness probes are health checks provided by Kubernetes for containers. A liveness probe checks whether a container...