TCPDUMP useful commands for debugging

How to Install tcpdump in Linux:

$ sudo apt-get install tcpdump  [On Debian, Ubuntu and Mint]

$ sudo yum install tcpdump           [On RHEL/CentOS/Fedora and Rocky Linux/AlmaLinux]

$ sudo emerge -a sys-apps/tcpdump    [On Gentoo Linux]

$ sudo pacman -S tcpdump             [On Arch Linux]

$ sudo zypper install tcpdump        [On OpenSUSE]    

Useful scenarios: 

Capture Packets from Specific Interface: tcpdump -i eth0

Capture Only N Number of Packets: tcpdump -c 5 -i eth0

Print Captured Packets in ASCII: tcpdump -A -i eth0

Display Available Interfaces: tcpdump -D

Display Captured Packets in HEX and ASCII: tcpdump -XX -i eth0

Capture and Save Packets in a File: tcpdump -w 0001.pcap -i eth0

Read Captured Packets File: tcpdump -r 0001.pcap

Capture IP Address Packets: tcpdump -n -i eth0

Capture only TCP Packets: tcpdump -i eth0 tcp

Capture Packet from Specific Port: tcpdump -i eth0 port 22

Capture Packets from source IP: tcpdump -i eth0 src 192.168.0.2

Capture Packets from destination IP: tcpdump -i eth0 dst 50.116.66.139

Reference: 

https://www.tecmint.com/12-tcpdump-commands-a-network-sniffer-tool/,

https://www.brianstorti.com/tcp-flow-control/,

https://www.researchgate.net/figure/TCPDump-Overview-shows-the-TCP-IP-Characteristics-flow-7_fig1_326419957

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