Generally you can use iptables to block or allow ping requests.
You can setup kernel variable to drop all ping packets. Type the following command at shell prompt:
# echo “1″ > /proc/sys/net/ipv4/icmp_echo_ignore_all
This instructs the kernel to simply ignore all ping requests (ICMP type 0 messages). To enable ping request type the command:
#echo “0″ > /proc/sys/net/ipv4/icmp_echo_ignore_all
You can add following line to /etc/sysctl.conf file:
# vi /etc/sysctl.conf
Append following line:
net.ipv4.icmp_echo_ignore_all = 1
Save and close the file.
