Tcpdump rule filtering, package grabbing and result filtering and viewing.

1, grab the packet with the specified IP address.

2. Grab the communication packet between the host and a specific IP (192. 168. 1 .200 or192.168.1).

3. Grab the communication packet between the host and a specific IP (192.168.438+0.200).

4. Grab the data packet of a specific port.

5. Grab the data packet of a specific network segment.

6. Grab specific protocol packets.

7. Conditional combination filtering and grabbing packages

8. Common logical expressions

No:! Or "no"

& amp:& amp； Or "and"

Or: || or "or"

1. If the domain name is not resolved, the contents of the third column will be displayed by IP address, and sort -u will be repeated.

2. Filter packets with source IP192.168.1.100.

3. Filter the packets with the destination IP of192.168.1.100.

4. Use port 50 to filter packets.

5. Display the packet information of port 80 in 16.