Docker Basics

This document covers the Docker basic commands which a basic HTML webpage is running in a container. The Docker container is created on Linode. Sign up for an account if you do not have one.

• Search for docker in marketplace

  

• Create a VM on Linode. Choose your image, region, Linode plan, set your root password and click Create Linode

  

• On cmd, ssh into your VM via the command of ssh root@<your-VM-IP-address>. Enter your root password.

• In your desired directory, create a src folder and a Dockerfile

  

• Create a index.html file in your src folder. You can customise the html file to your liking.

  

• Return to the Dockerfile and include the following commands

  • FROM nginx:latest --> using the latest image of nginx for the container
  • COPY src/index.html /usr/share/nginx/html --> copy the index.html in src folder to /usr/share/nginx/html
  • EXPOSE 80 --> Docker container listen on port 80
  • CMD ["nginx", "-g", "daemon off;"] --> Run nginx with daemon off when container starts up

  

• Return to the directory where the Dockerfile is located and build the docker image with following command, where -t means tagging.

  docker build -t <website-name> .

• Enter the following command to check if the image has been created.

  docker images

• To run the docker container in detached mode and listen on port 8080 of host, enter the following

  docker run -d -p 8080:80 <website-name>

• To check if the container is running, enter the following

  docker ps

• Open the web browser and enter the following to see the webpage

  http://<your-VM-IP-address>:8080

• To stop the container, enter the following

  docker stop <container ID>

• To remove the container, enter the following

  docker rm <container ID>

• Before pushing the image into Docker hub, register an account and create a new repository, the name of repository has to be unique within your account

  

• Enter the following on cmd to login your docker hub account and press ENTER. You will be prompted to enter password.

  docker login --username=<your-username>

• To push the docker image into your repository, enter

  docker tag <image id> <your docker hub username>/<docker hub repo name>:latest

  docker push <your docker hub username>/<docker hub repo name>:latest

• Return to your docker hub account and the pushed image will be listed.