https://www.tcpdump.org/

Powerful command-line packet analyzer

使用例子：

```sh sudo tcpdump -n -i any port 53 -v

sudo tcpdump -i any port 8000

sudo tcpdump -n -v -i any port 8000 and host 1.2.3.4

```

CheatSheet(from https://www.comparitech.com/net-admin/tcpdump-cheat-sheet/ )：


参考资料：

1. https://jvns.ca/tcpdump-zine.pdf