源地址 /etc/yum.repo.d/ 先安装wget命令
yum -y install wget 备份 cd /etc/yum.repo.d/ mkdir bak mv * bak/ 下载阿里云源 centos 5 wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-5.repo centos6 wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-6.repo centos 7 wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo 整理缓存 yum clean all #清除所有缓存，可以不执行 yum makecache #生成缓存 安装eple源 安装eple之后， 才能yum安装nginx，redis等 yum install -y epel-release