Ubuntu Server 20.04 – Allowing SSH root login

To enable root password login over ssh in order to edit the files type

sed -i s/^\#PermitRootLogin\ prohibit-password$/PermitRootLogin\ yes/ /etc/ssh/sshd_config 
systemctl restart ssh

You can later change this back by typing

sed -i s/^PermitRootLogin\ yes/PermitRootLogin\ prohibit-password/ /etc/ssh/sshd_config 
systemctl restart ssh

Open the /etc/ssh/sshd_config file with administrative privileges and change the following line:

FROM:
#PermitRootLogin prohibit-password
TO:
PermitRootLogin yes

sudo systemctl restart ssh