Iptables

The syntax is as follows to block incoming port using IPtables:

/sbin/iptables -A INPUT -p tcp --destination-port {PORT-NUMBER-HERE} -j DROP

1. 1. 1. interface section use eth1 ###

/sbin/iptables -A INPUT -i eth1 -p tcp --destination-port {PORT-NUMBER-HERE} -j DROP

1. 1. 1. only drop port for given IP or Subnet ##

/sbin/iptables -A INPUT -i eth0 -p tcp --destination-port {PORT-NUMBER-HERE} -s {IP-ADDRESS-HERE} -j DROP /sbin/iptables -A INPUT -i eth0 -p tcp --destination-port {PORT-NUMBER-HERE} -s {IP/SUBNET-HERE} -j DROP