localinstall 是安装在本地的rpm包顺便解决依赖关系
yum localinstall docker-common-1.12.6-68.gitec8512b.el7.centos.x86_64.rpm –y
yum localinstall docker-client-1.12.6-68.gitec8512b.el7.centos.x86_64.rpm -y
yum localinstall docker-1.12.6-68.gitec8512b.el7.centos.x86_64.rpm -y