tcpdump

One-Liners: tcpdump

Helpful tcpdump commands.
Add -v to -vvvv to see from some to a lot of information.

Get CDP or LLDP information.

tcpdump -i enp132s0f0 -v -s 1500 -c 1 '(ether[12:2]=0x88cc or ether[20:2]=0x2000)'

Watch DHCP traffic

tcpdump -i enp1s0f0  port 67 or port 68 -e -n -vv

Show VLAN tags

tcpdump -i enp1s0f0  -e vlan -nn

Watch for 1 host

tcpdump -vvvv -n dst host 10.200.200.13 or src host 10.200.200.13