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

Chapter 11. Zero Downtime Deployments and Secrets

In the last chapter, we explored Docker Swarm and its resources in detail. We learned how to build a highly available swarm locally, and in the cloud. Then, we discussed swarm services and stacks in depth. Finally, we created services and stacks in the swarm.

In this chapter, we will show you how we can update services and stacks running in Docker Swarm without interrupting their availability. This is called zero downtime deployment. We are also going to introduce swarm secrets as a means to securely provide sensitive information to containers of a service using those secrets.

The topics of this chapter are:

  • Zero downtime deployment
  • Secrets

After finishing this chapter, you will be able to:

  • List two to three different deployment strategies commonly used to update a service without downtime
  • Update a service in batches without causing a service interruption
  • Define a rollback strategy for a service that is used if an update fails
  • Use a secret with a...