P0f - OS Fingerprinting

p0f is a passive TCP/IP stack fingerprinting tool. p0f can attempt to identify the system running on machines that send network traffic to the box it is running on, or to a machine that shares a medium with the machine it is running on.

Example:
p0f -i any -p -o /tmp/sniff.log

1. The -i switch corresponds to the interface
2. By setting the -p switch, we are setting the tool to run in promiscuous mode.
3. We are setting the p0f tool to store the output (-o) in /tmp location inside a file named sniff.log.

NMAP - Subnet Scan

nmap -sP 172.20.20.1-255

This displays all the hosts that are up in the network within a minute.

 nmap -T4 -A 172.20.20.14