Appendix A: Chapter quiz answers

This appendix lists the answers to all the in-chapter quizzes. See Appendix B for the answers to the Sample Test.

Chapter 1: Setting the scene

Question 1, answers A, B, D

Answer C is not correct because containers are less secure than virtual machines. This is due to the shared kernel model.

Question 2, answer B

Every virtual machine has its own kernel and is therefore more secure than a container. However, this makes them bigger, slower to start, and not a good fit for microservices architectures.

Question 3, answer D

Each container is a virtual operating system with its own root filesystem, its own process tree, and its own eth0 network interface.

Question 4, answers A, D

Containers virtualise operating system constructs such as process trees and filesystems. They do not virtualise hardware constructs such as CPUs and hard drives.

Question 5, answer A

Containers all share the OS and kernel of the host they’re running on. This makes them smaller than virtual machines and means you can run more containers on a host than virtual machines.

Question 6, answer D

Containers...

Chapter 2: Cloud native architecture

Question 1, answer B

Resiliency is the ability for applications and infrastructure to self-heal.

Question 2, answer C

Applications and infrastructure can both be resilient. Kubernetes implements controllers, such as the deployment controller, to make applications resilient. Many cloud platforms allow you to build node pools that are resilient.

Question 3, answer A

Things fail all the time. Designing with failure in mind allows applications to continue working when things fail.

Question 4, answer C

Loose coupling means different components aren’t reliant on each other and can be less impacted when other components fail.

Question 5, answer D

Reconciliation is the process of synchronising observed state with desired state.

Question 6, answer A

/healthz is a common endpoint for application health checks and probes.

Question 7, answer D

Health checks are a good way to test whether an application is functioning...

Chapter 3: Container orchestration

Question 1, answers A, D

Containers are similar to virtual machines. However, they share the host’s kernel making them more lightweight than virtual machines. You normally run one small, single-purpose application per container.

Question 2, answer A

Containers are smaller and more lightweight than virtual and physical machines. This means you can run more apps if you use containers.

Question 3, answer A

Containers are smaller and more lightweight than virtual machines, making them easier to package and share. Containers also package application source code and all dependencies meaning they will work the same in production as they do on a developer’s laptop – this also makes them better for sharing.

Question 4, answer B

Kubernetes and containers don’t care what languages your applications are written in.

Question 5, answer D

A container image holds application code and all dependencies.

Question 6, answer...

Chapter 4: Kubernetes fundamentals

Question 1, answer D

Kubernetes was released in 2014.

Question 2, answers A, B, D

Kubernetes is a container orchestrator and can add self-healing, autoscaling, and zero-downtime rolling-updates to containerised applications. Image scanning is usually provided by registries or CI/CD pipelines.

Question 3, answers A, B, D

Kubernetes natively orchestrates containers. KubeVirt extends it to be able to orchestrate virtual machines, whereas OpenFaaS and Knative extend it to be able to orchestrate serverless functions.

Question 4, answer B

KubeVirt enables Kubernetes to manage virtual machine workloads inside of pods. Knative and OpenFaaS are for serverless, whereas Cilium is a network plugin.

Question 5, answers A, D

OpenFaaS and Knative extend Kubernetes for serverless function workload orchestration. Cilium is a network plug, and KubeVirt enables virtual machine workloads on Kubernetes.

Question 6, answer B

Linkerd provides service...

Chapter 5: Cloud native application delivery

Question 1, answers A, C

“Release” and “rollout” both refer to the process up replacing an existing version of an app with an updated version.

Question 2, answer C

Continuous Integration (CI) allows developers to automate the building and testing of application code.

Question 3, answer A

Continuous Integration (CI) is a great way or identifying bugs and other issues before the code gets to production.

Question 4, answer A

Continuous Deployment (CD) is the process of automating the deployment of updates to live environments.

Question 5, answer C

CI/CD enables frequent releases and is a cornerstone of DevOps workflows.

Question 6, answer D

Jenkins is a popular CI/CD tool. Kubernetes and Swarm are both container orchestrators and Docker is a company, container orchestrator, and container runtime.

Question 7, answer B

Using CI/CD tools to automate building and testing allows developers to...

Chapter 6: Cloud native observability

Question 1, answer D

Telemetry is log data, metrics, and traces that are output from a system.

Question 2, answers A, B, C

The three main classes of telemetry data are logs, metrics, and traces.

Question 3, answer D

Prometheus stores data in a timeseries format.

Question 4, answer B

Telemetry is used to troubleshoot and tweak performance of a system.

Question 5, answers B

The OpenTelemetry projects provides instrumentation and specifications for cloud native observability.

Question 6, answer B

Log data is application output that is usually output as text or JSON.

Question 7, answer C

Log events are often categorised from lowest to highest severity in the following order: info > warning > error > critical.

Question 8, answer A

High verbosity generates more output than low verbosity.

Question 9, answer C

Debug level is the most verbose and intended to dump out as much data as possible.

Question 10, answers...