One of the first tasks to perform when you have identified a target network is to check which hosts are live. A simple way of achieving this is to ping an IP address and confirm whether or not a reply is received. However, doing this for more than a few hosts can quickly become a draining task. This recipe aims to show you how you can achieve this with Scapy.

Scapy is a powerful tool that can be used to manipulate network packets. While we will not be going into great depth of all that can be accomplished with Scapy, we will use it in this recipe to determine which hosts reply to an Internet Control Message Protocol (ICMP) packet. While you can probably create a simple bash script and tie it together with some grep filtering, this recipe aims to show you techniques that will be useful for tasks involving iterating through IP ranges, as well as an example of basic Scapy usage.

Scapy can be installed on the majority of Linux systems with the following command...