curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo
非阿里云 ECS 用户会出现 Couldn't resolve host 'mirrors.cloud.aliyuncs.com' 信息，不影响使用。用户也可自行修改相关配置: eg:
sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo
yum install -y https://mirrors.aliyun.com/epel/epel-release-latest-7.noarch.rpm
sed -i 's|^#baseurl=http://download.fedoraproject.org/pub|baseurl=https://mirrors.aliyun.com|' /etc/yum.repos.d/epel*
sed -i 's|^metalink|#metalink|' /etc/yum.repos.d/epel*