#!/bin/bash

sshd_dns () {
local dir	
local dnsconf
local conf
dir=${1:-"/etc/ssh/sshd_config.d"}
pushd "$dir" 1>/dev/null || return;
for dnsconf in *.conf.dns; do
    [[ -f "$dnsconf" ]] || break
    conf=$(basename $dnsconf .dns)
    echo "----- processing sshd file $dnsconf to $conf ----"
    sudo cp $dnsconf $conf
    cat $conf
    echo -e "\n------------"
	for host in $(sed -e 's/[ ,]/\n/g' $conf | sed -n 's/[Dd][Nn][Ss]://p'); do
	echo found host $host, substituting $(dig +short $host) 
	sudo sed -i 's/[Dd][Nn][Ss]:'$host'/'$(dig +short $host)'/g' $conf
	done
    echo "----- created sshd conf file $conf ----"
    cat $conf
    echo -e "\n------------"
  done
echo restart ssh service daemon to enable these changes  
popd 1>/dev/null || return 

}