Create a Dockerfile

Docker Images start from a base image. The base image should include the platform dependencies required by your application, for example, having the JVM or CLR installed. This base image is defined as an instruction in the Dockerfile. Docker Images are built based on the contents of a Dockerfile. The Dockerfile is a list of instructions describing how to deploy your application.

# base image
FROM nginx:alpine
# copies the content of the current directory into a particular location (/usr/share/nginx/html)inside the container.
COPY . /usr/share/nginx/html

Build docker image

The Dockerfile is used by the Docker CLI build command. The build command executes each instruction within the Dockerfile. The result is a built Docker Image that can be launched and run your configured app. The build command takes in some different parameters. The format is docker build -t build-directory. The -t parameter allows you to specify a friendly name for the image and a tag, commonly used as a version number. This allows you to track built images and be confident about which version is being started.

# Build our static HTML image using the build command below.
# The built image will have the name webserver-image with a tag of v1.
docker build -t webserver-image:v1 .
# view a list of all the images on the host
docker images


The built Image can be launched in a consistent way to other Docker Images. When a container launches, it’s sandboxed from other processes and networks on the host. When starting a container you need to give it permission and access to what it requires. For example, to open and bind to a network port on the host you need to provide the parameter -p host-port:container-port.

# Launch our newly built image providing the friendly name and tag. As it's a web server, bind port 80 to our host using the -p parameter.
docker run -d -p 80:80 webserver-image:v1
# Access the results of port 80
curl docker

dockerfile and index.html

# index.html
<h1>Hello World</h1>