Use of the tcpdump command

The main purpose of this command is: check the communication protocol is packet sending, data callback is normal, used to determine the interface, network fault tcpdump-ieth0 (local NIC number) hostBBB (BBB indicates the IP address of the host that needs to be accessed remotely)-s0-v-X #-I indicates the interface, the local port scan interface means, plus tcpdump-ieth0 such as eth0, etho: 1

The main purpose of this command is to check whether the communication protocol has packet sending and data callback functions properly. it is used to determine interfaces and network faults.

Tcpdump-I eth0 (NIC number of the local machine) host BBB (BBB indicates the IP address of the host to be accessed remotely)-s0-v-X

#-I indicates the interface, which indicates the interface of the local port, plus eth0, etho: 1, etc.

Tcpdump-I eth0: 1 host 202.101.111.111-s0-v-X

# Host 202.101.111.111 indicates that the host IP address is remotely accessed.