Docker Note One

images & containers

• A container is a stripped-to-basics version of a Linux operating system.
• An image is software you load into a container.

Dockerfile

• The FROM keyword tells Docker which image your image is based on.
• Build an image from your Dockerfile
• docker build -t docker-whale .
• docker run docker-whale

Tag, push, and pull your image

• docker tag 7d9495d03763 anggao/docker-whale:latest
• docker login to log into the Docker Hub
• docker push anggao/docker-whale

Remove images

• docker rmi -f 7d9495d03763
• docker rmi -f docker-whale

Pull images

• docker pull anggao/docker-whale

install Docker using Docker Toolbox

• Docker Machine for running the docker-machine binary

• Docker Engine for running the docker binary

• Docker Compose for running the docker-compose binary

• Kitematic, the Docker GUI

• You use docker-machine to create and attach to a virtual machine (VM).

• In networking, localhost means your computer.

• The Docker host is the computer(system) on which the containers run.

• In an OS X installation, the docker daemon is running inside a Linux VM called default

• The VM runs completely from RAM, is a small ~24MB download, and boots in approximately 5s

docker-machine

• Create a new Docker VM.
• docker-machine create --driver virtualbox default
• The command also creates a machine configuration in the ~/.docker/machine/machines/default
• List your available machines.
  • docker-machine ls
• Get the environment commands for your new VM.
  • docker-machine env default
• To remove a VM
  • docker-machine rm <machine-name>

Access container ports

• Start an NGINX container on the DOCKER_HOST
  • docker run -d -P --name web nginx
  • -d flag keeps the container running in the background
  • The -P flag publishes exposed ports from the container to your local host; this lets you access them from your Mac
• To stop and then remove your running nginx container, do the following:
  • docker stop web
  • docker rm web

Mount a volume on the container

• When you start a container it automatically shares your /Users/username directory with the VM.
• You can use this share point to mount directories onto your container.
• docker run -d -P -v $HOME/site:/usr/share/nginx/html --name mysite nginx
• Get the mysite container’s port.
• docker port mysite