Set the root user password
sudo passwd root
Password: <--- Enter your current user password
Enter new UNIX password: <--- New Root user password
Retype new UNIX password: <--- Repeat the new Root user password
Allow LAN access: use bridge mode
Install apt-get install openssh-server
Allow root user remote access
install apt-get install vim-gtk
vi /etc/ssh/sshd_config
Change the PermitRootLogin value to yes
service sshd restart 或/etc/init.d/sshd restart