Home page logo
Zenmap screenshot
Intro Reference Guide Book Install Guide
Download Changelog Zenmap GUI Docs
Bug Reports OS Detection Propaganda Related Projects
In the Movies In the News
Example Nmap output

Nmap Network Scanning

Periodic Diffs

Using Nmap, Ndiff, cron, and a shell script, it's possible to scan a network daily and get email reports of the state of the network and changes since the previous scan. Example 16.3 shows the script that ties it together.

Example 16.3. Scanning a network periodically with Ndiff and cron

OPTIONS="-v -T4 -F -sV"
date=`date +%F`
cd /root/scans
nmap $OPTIONS $TARGETS -oA scan-$date > /dev/null
if [ -e scan-prev.xml ]; then
        ndiff scan-prev.xml scan-$date.xml > diff-$date
        echo "*** NDIFF RESULTS ***"
        cat diff-$date
echo "*** NMAP RESULTS ***"
cat scan-$date.nmap
ln -sf scan-$date.xml scan-prev.xml

If the script is saved as /root/scan-ndiff.sh, add the following line to root's crontab:

0 12 * * * /root/scan-ndiff.sh

[ Nmap | Sec Tools | Mailing Lists | Site News | About/Contact | Advertising | Privacy ]