Key-Only Login

SSH-Config 
 nano /etc/ssh/sshd_config
 
 Wichtige Einstellungen 
 PasswordAuthentication no
ChallengeResponseAuthentication no
UsePAM no
PermitRootLogin prohibit-password
PermitEmptyPasswords no
Protocol 2
LoginGraceTime 60
MaxAuthTries 3
X11Forwarding no
 
 SSH neustarten: 
 systemctl restart sshd