To secure the server , we would disable direct root login. That could be done via sshd_config file.
Here Protocol 2 needs to be used which is more secure.
Refer the following steps for the same:-
1) vi /etc/ssh/sshd_config
2) Change Protocol 2,1 to Protocol 2
4) PermitRootLogin yes = no
5) Restart SSHD: /etc/rc.d/init.d/sshd restart