~~~ yum -y install lsof wget net-tools vim mv /etc/yum.repos.d /etc/yum.repos.d.backup.20180408 mkdir /etc/yum.repos.d wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo yum clean all yum makecache ~~~ ~~~ systemctl stop firewalld.service #停止firewall systemctl disable firewalld.service #禁止firewall开机启动 firewall-cmd --state #查看默认防火墙状态（关闭后显示notrunning，开启后显示running） ~~~