Ubuntu : Enable root login

Solution 1. Edit #/etc/ssh/sshd_config

Change PermitRootLogin prohibit-password to yes

Solution 2. Run the command

#sudo sed -i 's/prohibit-password/yes/' /etc/ssh/sshd_config

3. Create password to root login

#passwd root


Source:

• https://linuxconfig.org/enable-ssh-root-login-on-ubuntu-16-04-xenial-xerus-linux-server-desktop