Look this bash script maybe it help you :
log to your server and do this
It'll create a cron to run it every 5 minutes, but you can run it manually with "cd /usr/local/ddos/;./ddos.sh". or
Code:
cd /usr/local/ddos/
sh ddos.sh
You can configure it here :
nano /usr/local/ddos/ddos.conf
Set NO_OF_CONNECTIONS=60 and BAN_PERIOD=10000
but you can , run it manually to block IPs rapidly.
More informations >
http://deflate.medialayer.com/