tcpdump

Dump traffic on a network.

• Capture the traffic of a specific interface:

tcpdump -i {{eth0}}

• Capture all TCP traffic showing contents (ASCII) in console:

tcpdump -A tcp

• Capture the traffic from or to a host:

tcpdump host {{www.example.com}}

• Capture the traffic from a specific interface, source, destination and destination port:

tcpdump -i {{eth0}} src {{192.168.1.1}} and dst {{192.168.1.2}} and dst port 80

• Capture the traffic of a network:

tcpdump net {{192.168.1.0/24}}

• Capture all traffic except traffic over port 22 and save to a dump file:

tcpdump -w dumpfile.pcap not port 22