Book Image

Docker Certified Associate (DCA): Exam Guide

By : Francisco Javier Ramírez Urea
Book Image

Docker Certified Associate (DCA): Exam Guide

By: Francisco Javier Ramírez Urea

Overview of this book

Developers have changed their deployment artifacts from application binaries to container images, and they now need to build container-based applications as containers are part of their new development workflow. This Docker book is designed to help you learn about the management and administrative tasks of the Containers as a Service (CaaS) platform. The book starts by getting you up and running with the key concepts of containers and microservices. You'll then cover different orchestration strategies and environments, along with exploring the Docker Enterprise platform. As you advance, the book will show you how to deploy secure, production-ready, container-based applications in Docker Enterprise environments. Later, you'll delve into each Docker Enterprise component and learn all about CaaS management. Throughout the book, you'll encounter important exam-specific topics, along with sample questions and detailed answers that will help you prepare effectively for the exam. By the end of this Docker containers book, you'll have learned how to efficiently deploy and manage container-based environments in production, and you will have the skills and knowledge you need to pass the DCA exam.
Table of Contents (22 chapters)
1
Section 1 - Key Container Concepts
8
Section 2 - Container Orchestration
12
Section 3 - Docker Enterprise
17
Section 4 - Preparing for the Docker Certified Associate Exam

Image releases and updates

Earlier, we mentioned how we should manage image updates. In that instance, we were focused on security updates to avoid bugs and exploits in production. Similarly, we can apply this concept to application fixes and releases.

Base images should be updated in critical image components and these changes do not happen very frequently. Usually, the application releases are weekly or even daily (or hourly, depending on numerous factors, such as business requirements and critical fixes).

Depending on how many containers are running based on a specific image, a new image release can be a big change. These changes can be done in a couple of minutes or they can take you an hour. However, the procedure using containers is very quick; let the orchestrator do its job. Kubernetes and Swarm will provide automated image updates and rollback and we will be able to manage how this deployment should be done, how many containers will update their images in parallel, how much...