yun -y install openssh-server //默认系统是安装过的，没安装的进行安装
    vi /etc/ssh/sshd_config //编辑ssh配置文件
    Port 22 //去掉文件#Port 22前#号
    PermitRootLogin yes //去掉文件#PermitRootLogin yes前#号，使root能登录
    systemctl start sshd.service //启动ssh
    systemctl enable sshd.service //开机启动ssh
    systemctl status sshd.service //显示ssh配置状态
    //其它,每次修改配置文件需重启ssh生效
    systemctl stop sshd.service //停止ssh
    systemctl restart sshd.service //停止ssh
    systemctl disable sshd.service //开机停止启动ssh