sshd

Installation

sh# apt install openssh-server

Configuration

/etc/ssh/sshd_config

sh# vi /etc/ssh/sshd_config
...
UsePrivilegeSeparation yes
ServerKeyBits          4096
PermitRootLogin        no
PasswordAuthentication no
PubkeyAuthentication   yes
AuthorizedKeysFile     %h/.ssh/authorized_keys

ssh-key authentication

sh# ssh-keygen -C <FQDN> -b 4096 -t rsa -f <FQDN>