Monitoring and get all the IP's of a Fast Flux domain and scan with nmap

fast-flux-scanner.sh

#!/bin/bash

# cd
# mkdir domain.com
# cd domain.com
# mkdir nmap
# add crontab job every minute: 
# * * * * * /home/user/fast-flux-scanner.sh domain.com /home/user/domain.com >/dev/null 2>&1

domain=$1
path_job=$2

cd "$path_job"
hosts=$(host -t A "$domain" | awk '{print $4}')
echo "$hosts" >> hosts_history.txt
hosts_uniq=$(cat hosts_history.txt | sort | uniq)
echo "$hosts_uniq" > hosts_history.txt
while read line; do
        ls "nmap/$line" &>/dev/null
        if [ $? -eq 0 ] ; then
                echo "nmap ok"
        else
                nohup nmap -v -sT -T4 -Pn -p- -A -oN "nmap/$line" "$line" &
        fi
done <<< "$hosts"