Block an IP Address

If you think you are being attacked by an IP Address, you could block it by either firewall like:
iptables -A INPUT -s <ip-address> -j DROP
or if you want to block that IP from accessing a specific port, do:
iptables -A INPUT -s -<ip-address> p tcp --destination-port <port> -j DROP (to unlock, replace "-A" with "-D")

or using the standard route command like: /sbin/route add -host<ip-address>reject (to unblock replace the "add" part with "del")