Hardening ssh

Prevent root logins via ssh

/etc/ssh/sshd_config

add this line PermitRootLogin no

find the line that says Protocol 2,1 and change it to Protocol 2

AllowUsers carla fobber@mubble.com lori meflin
AllowGroups admin
Port 222
PasswordAuthentication no

see man 5 sshd_config