Linux disable or drop / block ping packets all together

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.