----------CentOS 7---------------------
sudo adduser --system --no-create-home --user-group -s /sbin/nologin docker
sudo yum -y update
sudo cat >> /etc/yum.repos.d/docker.repo <<-‘EOF‘
[dockerrepo]
name=Docker Repository
baseurl=https://yum.dockerproject.org/repo/main/centos/$releasever/
enabled=1
gpgcheck=1
gpgkey=https://yum.dockerproject.org/gpg
EOF
sudo yum install -y docker-engine
sudo yum -y install python-setuptools
sudo easy_install pip
sudo pip install docker-compose
# do this step if ‘/data‘ is the big storage than ‘/‘
sudo systemctl stop docker.service
sudo mkdir -p /data/docker-var/docker
sudo rm -rf /var/lib/docker
sudo ln -s /data/docker-var/docker /var/lib/docker
sudo sed -i ‘s:ExecStart=/usr/bin/docker daemon -H fd\://:ExecStart=/usr/bin/docker daemon -H fd\:// --log-opt max-size=100m --log-opt max-file=50:g‘ /lib/systemd/system/docker.service
sudo systemctl daemon-reload
sudo systemctl restart docker.service
-------------Ubuntu 16.04---------------------
https://docs.docker.com/engine/installation/linux/ubuntulinux/
#sudo apt-get update
#sudo apt-get install apt-transport-https ca-certificates
sudo apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 58118E89F3A912897C070ADBF76221572C52609D
echo ‘deb https://apt.dockerproject.org/repo ubuntu-xenial main‘>/etc/apt/sources.list.d/docker.list
sudo apt-get update
#sudo apt-get purge lxc-docker
apt-cache policy docker-engine
#sudo apt-get install linux-image-extra-$(uname -r)
sudo apt-get update
sudo apt-get install docker-engine
sudo service docker start
sudo groupadd docker
sudo usermod -aG docker ubuntu
sudo apt-get install python-pip
sudo pip install docker-compose
sudo ufw status
sudo nano /etc/default/ufw
# "DEFAULT_FORWARD_POLICY="ACCEPT""
sudo ufw allow 2375/tcp
sudo ufw reload