1.关闭禁用防火墙和selinuxsystemctl disable firewalld --now sed -i s/SELINUXenforcing/SELINUXdisabled/ /etc/selinux/config2.保证可以连接外网ping -c3 www.baidu.com3.配置yum为阿里仓库并下载epel源mkdir /etc/yum.repos.d/bak/; mv /etc/yum.repos.d/*.repo /etc/yum.repos.d/bak/ curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo curl -o /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo#清理yum缓存并刷新元数据yum clean all yum makecache fast#查看仓库是否有rpm包yum repolist