To disable root login please perform these steps:
1. SSH into your server as ‘admin’ and gain root access by su.
2. Edit this file for SSH logins: vi /etc/ssh/sshd_config
3. Find the line: Protocol 2, 1
4. Uncomment it and change it to: Protocol 2
5. Next, find the line: PermitRootLogin yes
6. Uncomment it and change it to: PermitRootLogin no
7. Save the file to apply changes.
8. Now you can restart SSH
Now, no one will be able to login to root with out first loggin in as admin and ‘su -‘ to root, and you will be forcing the use of a more secure protocol. Just make sure you remember both passwords!
Note: If you are using cPanel server make sure you have added admin user to the ‘wheel’ group so that you will be able to ‘su -‘ to root, otherwise you may lock yourself out of root.