My server has a 100mbps port and sometimes I get DDoS attacks which most times use up the whole port. I was wondering if it is possible to drop the bandwidth if it is let's say more than 1mbps from an IP? Which CSF configuration allows to do that and do you have any other tips on mitigating DDoS attack?
Look into the SYNFLOOD settings in CSF. Honestly though, if you are actually getting ddos, you need to stop it before it gets to your server. The traffic still has to go through your network and down to your NIC before you can do anything about it on the server side.
Affordable web hosting, design, & domain registration services since 2001 www.serve-you.net