Book Image

Docker Orchestration

By : Arbezzano, Randall Smith
Book Image

Docker Orchestration

By: Arbezzano, Randall Smith

Overview of this book

Docker orchestration is what you need when transitioning from deploying containers individually on a single host to deploying complex multi-container apps on many machines. This book covers the new orchestration features of Docker 1.12 and helps you efficiently build, test, and deploy your application using Docker. You will be shown how to build multi-container applications using Docker Compose. You will also be introduced to the building blocks for multi-host Docker clusters such as registry, overlay networks, and shared storage using practical examples. This book gives an overview of core tools such as Docker Machine, Swarm, and Compose which will enhance your orchestration skills. You’ll learn how to set up a swarm using the decentralized building block. Next, you’ll be shown how to make the most out of the in-built orchestration feature of Docker engine and you’ll use third-party tools such as Kubernetes, Mesosphere, and CoreOS to orchestrate your existing process. Finally, you will learn to deploy cluster hosts on cloud services and automate your infrastructure.
Table of Contents (11 chapters)

Managing a swarm

One of the easiest pieces to overlook when it comes to orchestrating Docker is how to manage the cluster itself. In this section, you will see how to manage your swarm including adding and removing nodes, changing their availability, and backup and recovery. In Chapter 10, Why Stop at Containers? Automating Your Infrastructure, we will learn about automating node deployment in depth.

Adding a node

New worker nodes can be added at any time. Install Docker, then run docker swarm join-token worker to get the docker swarm join command to join the host to the swarm. Once added, the worker will be available to run tasks. Take note that the command to join the cluster is consistent. This makes it easy to add to a host configuration script and join the swarm on boot.

You can get a list of all of the nodes in the swarm by running docker node ls from a manager node:

$ docker node ls
ID                     HOSTNAME  STATUS  AVAILABILITY  MANAGER STATUS
1i3wtacdjz5p509bu3l3qfbei    worker1...