Root login over SSH can be required to carry out several operations and allow connection from other servers.
Enable root login over SSH:
1. With root login, edit the file sshd_config file located under /etc/ssh/sshd_config directory with your favorite file editor; vi or nano.
vi /etc/ssh/sshd_config
2. Go to the line that says PermitRootLogin yes, and remove the “#” sign in order to comment it out.
# Authentication:
#LoginGraceTime 2m
PermitRootLogin yes
#StrictModes yes
#MaxAuthTries 6
#MaxSessions 10
3. Now save the file with ‘wq’ if using vi editor or ‘Ctrl + O’ & type ‘Ctrl + X’ to save & exit in nano editor.
4. Finally, restart the SSH server to amend the changes.
service sshd restart
You are now ready to connect to the server as root over SSH.