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

Secrets


Secrets are used to work with confidential data in a secure way. Swarm secrets are secure at rest and in transit. That is, when a new secret is created on a manager node, and it can only be created on a manager node, its value is encrypted and stored in the raft consensus storage. This is why it is secure at rest. If a service gets a secret assigned to it, then the manager reads the secret from storage, decrypts it, and forwards it to all the containers who are instances of the Swarm service that requests the secret. Since the node-to-node communication in swarm is using mutual transport layer security (TLS), the secret value, although decrypted, is still secure in transit. The manager forwards the secret only to the worker nodes on which a service instance is running. Secrets are then mounted as files into the target container. Each secret corresponds to a file. The name of the secret will be the name of the file inside the container, and the value of the secret is the content of...