Disable Password Login

Make a backup of the current ssh configuration

• cd /etc/ssh/
• cp sshd_config sshd_config.bak

Edit /etc/ssh/sshd_confg:

# diff /etc/ssh/sshd_config /etc/ssh/sshd_config.bak 
< PasswordAuthentication no
---
> #PasswordAuthentication yes

Restart the ssh server

sudo service sshd restart