Book Image

Learn Docker - Fundamentals of Docker 19.x - Second Edition

By : Dr. Gabriel N. Schenker
Book Image

Learn Docker - Fundamentals of Docker 19.x - Second Edition

By: Dr. Gabriel N. Schenker

Overview of this book

Containers enable you to package an application with all the components it needs, such as libraries and other dependencies, and ship it as one package. Docker containers have revolutionized the software supply chain in both small and large enterprises. Starting with an introduction to Docker fundamentals and setting up an environment to work with it, you’ll delve into concepts such as Docker containers, Docker images, and Docker Compose. As you progress, the book will help you explore deployment, orchestration, networking, and security. Finally, you’ll get to grips with Docker functionalities on public clouds such as Amazon Web Services (AWS), Azure, and Google Cloud Platform (GCP), and learn about Docker Enterprise Edition features. Additionally, you’ll also discover the benefits of increased security with the use of containers. By the end of this Docker book, you’ll be able to build, ship, and run a containerized, highly distributed application on Docker Swarm or Kubernetes, running on-premises or in the cloud.
Table of Contents (25 chapters)
1
Section 1: Motivation and Getting Started
4
Section 2: Containerization, from Beginner to Black Belt
11
Section 3: Orchestration Fundamentals and Docker Swarm
18
Section 4: Docker, Kubernetes, and the Cloud

Using Prometheus to monitor a distributed application

Now that we have learned how to instrument an application service to expose Prometheus metrics, it's time to show how we can collect the metrics and forward them to a Prometheus server where all metrics will be aggregated and stored. We can then either use the (simple) web UI of Prometheus or a more sophisticated solution like Grafana to display important metrics on a dashboard.

Unlike most other tools that are used to collect metrics from application services and infrastructure components, the Prometheus server takes the load of work and periodically scrapes all the defined targets. This way applications and services don't need to worry about forwarding data. You can also describe this as pulling metrics versus pushing them. This makes Prometheus servers an excellent fit for our case.

We will now discuss how to deploy...