First you need to login to your Dedicated server as root via SSH. Then type the following command to see the number of connections the selected IP address has made to your server on a certain port:

netstat -plan|grep :PORT|awk {'print $5'}|cut -d: -f 1|sort|uniq -c|sort -nk 1 |grep IP_ADDRESS

Replace PORT and IP_ADDRESS with the correct values. You will then receive information about the number of connections this IP has made to your server.