Ubuntu_14.04安装docker
$ 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
$ sudo apt-get install vim
$ vim /etc/apt/sources.list.d/docker.list
deb https://apt.dockerproject.org/repo ubuntu-trusty main
$ sudo apt-get update
$ sudo apt-get purge lxc-docker
$ apt-cache policy docker-engine
$ sudo apt-get update
$ sudo apt-get install linux-image-extra-$(uname -r)
$ sudo apt-get update
$ sudo apt-get install docker-engine
$ sudo service docker start