Book Image

Learn Docker - Fundamentals of Docker 18.x

By : Dr. Gabriel N. Schenker
Book Image

Learn Docker - Fundamentals of Docker 18.x

By: Dr. Gabriel N. Schenker

Overview of this book

Docker containers have revolutionized the software supply chain in small and big enterprises. Never before has a new technology so rapidly penetrated the top 500 enterprises worldwide. Companies that embrace containers and containerize their traditional mission-critical applications have reported savings of at least 50% in total maintenance cost and a reduction of 90% (or more) of the time required to deploy new versions of those applications. Furthermore they are benefitting from increased security just by using containers as opposed to running applications outside containers. This book starts from scratch, introducing you to Docker fundamentals and setting up an environment to work with it. Then we delve into concepts such as Docker containers, Docker images, Docker Compose, and so on. We will also cover the concepts of deployment, orchestration, networking, and security. Furthermore, we explain Docker functionalities on public clouds such as AWS. By the end of this book, you will have hands-on experience working with Docker containers and orchestrators such as SwarmKit and Kubernetes.
Table of Contents (21 chapters)
Title Page
Packt Upsell
Contributors
Preface
Index

Questions


Please solve the following questions to assess your learning progress:

  1. Which statements are correct (multiple answers are possible)?
    1. A container is kind of a lightweight VM
    2. A container only runs on a Linux host
    3. A container can only run one process
    4. The main process in a container always has PID 1
    5. A container is one or more processes encapsulated by Linux namespaces and restricted by cgroups
  2. Explain to an interested layman in your own words, maybe using analogies, what a container is.
  3. Why are containers considered to be a game changer in IT? Name three to four reasons.
  4. What does it mean when we claim: If a container runs on a given platform then it runs anywhere...? Name two to three reasons why this is true.
  5. True or False: Docker containers are only really useful for modern greenfield applications based on microservices. Please justify your answer.
  6. How much does a typical enterprise save when containerizing their legacy applications?
    1. 20%
    2. 33%
    3. 50%
    4. 75%
  7. Which two core concepts of Linux are containers based on?