DevOps & Microservices. Part 3: Containers

Part 3 of the series, check part 2 first. In this post I explain the basics of containers.

Containers

In 2013 Docker was introduced, its popularity grew considerably and nowadays it is the de-facto standard to ship software. Containers were available before Docker in Linux, Docker introduced a simple local daemon process and a powerful REST API aligned with great tooling allowing this technology to rapidly grow. It also added a powerful registry and the efficient image layered system. One could argue that the Docker immutable images is the key to its success. Each portion of a container is divided into small images with have a unique hash ID, for example if you add a JDK to a existing Linux Container it will create a save that image, and if you create other containers the JDK portion will be taken from the cache instead of re building it which is much more efficient. An open container initiative was created to develop an standard.

Spring Cloud developers started to ship their microservices inside Docker containers making them easier to manage, scale and maintain; further more developers could developer in any language such as Node.js or Python.

Containers allow the DevOps team to manage the apps life cycle independently of the language or platform that they use. The way you deploy a…