Enable SSH root login on Ubuntu 16.04 Xenial Xerus Linux Server/Desktop

The root’s ssh remote shell access is denied by default. Any attempt to remote login as root will result in Permission denied message:

$ ssh [email protected]
[email protected]vps134.zetservers.com's password: Permission denied, please try again. [email protected]'s password:

In order to enable root ssh login on Ubuntu 16.04 Xenial Xerus Linux run the following command:

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

or manually open sshd configuration file /etc/ssh/sshd_config and change line:

PermitRootLogin prohibit-password
PermitRootLogin yes

Once you have made the above configuration change restart ssh daemon:

$ sudo systemctl restart sshd

After you restart sshd daemon you will be able to remotely login as a root user:

$ ssh [email protected]vps134.zetservers.com 
[email protected]vps134.zetservers.com's password: Welcome to Ubuntu 16.04 LTS (GNU/Linux 4.4.0-22-generic x86_64) * 
Documentation: https://help.ubuntu.com/ 22 packages can be updated. 20 updates are security updates. The programs included with the Ubuntu system are free software; the exact distribution terms for each program are described in the individual files in /usr/share/doc/*/copyright. Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by applicable law.