This will give you the basics in order to get the scanner running. Coding language = Linux Bash
run apt-get install postfix
run apt-get install nmap
Edit nmapEmail.sh for your network settings,
1. Copy to folder of you choice.
2. Run chmod 775 on all files.
3. Run ./nmapEmail.sh and it will scan and generate a report
4. Install into crontab using crontab -e and
*/30 * * * /PATH/TO/SCRIPTS/nmapEmail.sh (script will run every 5 minutes)
Run ./nmapEmail.sh
Email will be sent via postfix
Some ISPs are blocking the ability to send outbound Emails if that is the case use their SMTP settings using this link: http:https://www.cyberciti.biz/faq/postfix-smtp-authentication-for-mail-servers/