Iptables: how to drop incoming pings from host but allow ping responses?

Question

I am practicing with iptables and... I need a rule that will block a certain host from pinging me but will let me to ping the host if needed (so I need to accept ping responses right?). Can you help me?

Answer 1

You can block ping (icmp echo requests) from all hosts using this

iptables -I INPUT -j DROP -p icmp --icmp-type echo-request

If you want to block a particular host then

iptables -I INPUT -s 192.168.1.139 -j DROP -p icmp --icmp-type echo-request

Answer 2

Have a look at this page.