Creating Docker Image with Dockerfile

There are many way where you can create a Docker Image and make a container of it, but using Dockerfile is an easy way. Let's create an Apache Server Image using this method.

In this method we are going to follow below steps:

• First choose a __base_image__. In our case, base image is Ubuntu.
• Execute some commands while building the image. Actually it doesn't build whole new image it converts base image into Apache server image.

Okay, create a new folder and give whatever name you want to give it. I am giving it myapache and switching into it.

$ mkdir myapache
$ cd myapache

Create a new file named asDockerfile (not mandatory to use the same name). Add below commands into it.

FROM ubuntu
RUN "apt-get update"
RUN "apt-get install apache2 -y"

Let's breakdown these instructions step by step. First line says that we are using Ubuntu as __base_image__.

Second and third line says to run the given commands. apt-get update will install the latest version of packages currently installed on user's system. Next command will install Apache server on the __base_image__.

Here -y suggests automatic yes for any prompts in between the installing process.

Now using this Dockerfile let's build a docker image.

$ docker image build -t myapache .

You don't need to remember above command it is already present, docker image --help will help you. myapache is the name of the image.

One thing that i want to clarify that . is for the path of Dockerfile. I am currently in the same directory that's why i used put that.

So above command will build the docker image using our Dockerfile. It will run that instructions step by step.

$ docker image ls

Type above command and you will see that myapache image is listed there. That confirms that our image is created successfully.