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

Running in production


To successfully run a distributed application in production, we need to consider a few more aspects beyond the best practices and patterns presented in the preceding sections. One specific area that comes to mind is introspection and monitoring. Let's go through the most important aspects in detail.

Logging

Once a distributed application is in production, it is not possible to debug it. But how can we then find out what exactly is the root cause of a malfunction of the application that has been reported by a user? The solution to this problem is to produce abundant and meaningful logging information. Developers need to instrument their application services in such a way that they output helpful information, such as when an error happens or a potentially unexpected or unwanted situation is encountered. Often, this information is output to STDOUT and STDERR, from where it is then collected by system daemons that write the information to local files or forward it to a central...