按步骤一步步输入命令即可：
sudo -i
echo root:密码 |sudo chpasswd root
sudo sed -i 's/^#\?PermitRootLogin.*/PermitRootLogin yes/g' /etc/ssh/sshd_config;
sudo sed -i 's/^#\?PasswordAuthentication.*/PasswordAuthentication yes/g' /etc/ssh/sshd_config;
service sshd restart
rm -rf /etc/iptables/rules.v4
rm -rf /etc/iptables/rules.v6
