If you use a Webserver like Apache, you can use a small script to Analyse your Logs. Create a analyse-web.sh Script with:
$sudo nano /home/user/analyse-web.sh
insert:
#!/bin/bash
cat /var/log/apache2/access.log | awk '{ print $1 }' | sort | uniq -c
exit 0
System Output:
1573 www.domain2.de 3568 www.domain3.de ..
If you change the „$1“ to other value like „$8“ you will get the count of touched files or folders! This shows you attacks on single Files by abnormal high counts! You can use cron to run it every 15Minutes and send it to mailbox of a user. And this way does not need a PHP Tool with special PHP rights like webalizer or else..