安装docker 时候出现以下问题
yum -y install docker
Loaded plugins: fastestmirror
Determining fastest mirrors
* base: centos.uhost.hk
* extras: mirrors.btte.net
* updates: mirror.bit.edu.cn
base | 3.7 kB 00:00
base/primary_db | 4.7 MB 00:47
extras | 3.4 kB 00:00
extras/primary_db | 29 kB 00:00
updates | 3.4 kB 00:00
updates/primary_db | 2.5 MB 00:20
Setting up Install Process
No package docker available.
Error: Nothing to do
yum没有找到docker包，更新epel第三方软件库，运行命令：
sudo yum install epel-release
之后运行
sudo yum install docker-io即可
安装文档 http://www.runoob.com/docker/centos-docker-install.html