capture the network package used by tcpdump

In linux you can capture the network package used by tcpdump

1. sudo install tcpdmp,if you use debian .you can install it with

 apt install tcpdump

2. capture the newtork package used next command ,the network_interface_name can find by ip command.

sudo tcpdump -i netwrok_interface_name -w capture_name.pcap

3. download the capture_name.pcap and opened it with wireshark.