I run counter strike source instances on my server. Their are very few open ports on it, one being 27015, on which the instances can be connected to/queried. I've been DoS attacked a couple times now and I know the offending IPs, however I do not know how to ban/block these IPs from pinging/accessing my server. I'm sort of a noob here when it comes to windows server security. I don't have any sort of firewall other than windows firewall on my box. Is there any way I can block specific IPs from accessing my windows 2003 box with windows firewall?
If not, could you guys point out a few good windows 2003 software firewalls that aren't too cpu-intensive? All I want is to know the offending IPs, then have the ability to make my server "invisible" to those IP addresses. Any help is greatly appreciated!
Thanks
Ian