Install Docker on Ubuntu 14.04

Install Docker on Ubuntu 14.04

# Ref: https://docs.docker.com/engine/installation/linux/ubuntulinux/

# Update package information, ensure that APT works with the https method, and that CA certificates are installed.
sudo apt-get update
sudo apt-get install apt-transport-https ca-certificates

# Add the new GPG key.
sudo apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 58118E89F3A912897C070ADBF76221572C52609D

# Open the /etc/apt/sources.list.d/docker.list file in your favorite editor.
# If the file doesn’t exist, create it.
# Remove any existing entries.
# Add an entry for your Ubuntu operating system.
sudo gedit /etc/apt/sources.list.d/docker.list
# add this line
# deb https://apt.dockerproject.org/repo ubuntu-trusty main
# then save and close

# Update the APT package index.
sudo apt-get update

# Purge the old repo if it exists.
sudo apt-get purge lxc-docker

# Verify that APT is pulling from the right repository.
apt-cache policy docker-engine

# Update your package manager
sudo apt-get update

# Install the recommended packages.
sudo apt-get install linux-image-extra-$(uname -r) linux-image-extra-virtual

# Update your APT package index.
sudo apt-get update

# Install Docker.
sudo apt-get install docker-engine

# Start the docker daemon.
sudo service docker start

# Verify docker is installed correctly
sudo docker run hello-world