Docker Quick Start Guide

Building the Docker image

Let's get started. The first thing we want to do is build our specialized Docker image that can be used for our Jenkins agents. To do this, we are going to use the skills we learned in Chapter 3, Creating Docker Images, to create Docker images. Start by creating a new folder on your development system, and then change your working directory to that folder. I named mine jenkins-agent:

# Make a new folder to use for the build context of your new Docker image, and cd into itmkdir jenkins-agentcd jenkins-agent

Now create a new file, named Dockerfile, using your favorite editor, enter the following code into it, and then save it:

# jenkins-agent DockerfileFROM h1kkan/jenkins-docker:lts-alpineUSER rootARG user=jenkins ...