Tcpdump is a CLI tool to capture raw network packets. This is useful for various forms of network troubleshooting. This cheat sheet covers all the basic and advanced options for tcpdump.
Tcpdump command is a famous network packet analyzing tool that is used to display TCP\IP & other network packets being transmitted over the network attached to the system on which tcpdump has been installed. Tcpdump uses libpcap library to capture the network packets & is available on almost all Linux/Unix flavors.