1. 切换root用户: sudo -i
2. 设置root密码:passwd root
3. 以下3条命令:
sed -i 's/PermitRootLogin no/PermitRootLogin yes/g' /etc/ssh/sshd_config;sed -i 's/PasswordAuthentication no/PasswordAuthentication yes/g' /etc/ssh/sshd_config;reboot
原文:https://blog.csdn.net/u014633966/article/details/85539393