Reconfigure OpenSSH keys & to start on boot.

setup.sh

#!/bin/bash

# Uncomment a string within a given file
# $FILE is the targeted file
# $KEY is the string that is currently commented '#' (String must contain '#' or else 'sed' will return '1')
uncomment_str() {
    FILE="$1"
    KEY="$2"

    sed -i "$FILE" -e "/$KEY/s/#//g"
}

# Reconfigure OpenSSH Server
$(cd /etc/ssh && dpkg-reconfigure openssh-server)

# Configure OpenSSH runlevels
update-rc.d -f ssh remove
update-rc.d -f ssh defaults

$FILE="/etc/ssh/sshd_config"
$KEY="#PermitRootLogin yes"

if [ cat "$FILE" | grep "$KEY" ]; then
  # Configure '/etc/ssh/ssh_config' to allow 'root' login
  uncomment_str "$FILE" "$KEY"
  
  # retsart OpenSSH service
  sudo service ssh restart
fi

# Enable SSH on boot
update-rc.d -f ssh enable 2 3 4 5