snort
Open-source network intrusion detection system. tldr-pages
On several platforms
Several platforms
Capture packets with verbose output
sudo snort -v -i interfaceIdentifyCapture packets and dump application layer data with verbose output
sudo snort -vd -i interfaceIdentifyCapture packets and display link layer packet headers with verbose output
sudo snort -ve -i interfaceIdentifyCapture packets and save them in the specified directory
sudo snort -i interface -l path/to/directoryIdentifyCapture packets according to rules and save offending packets along with alerts
sudo snort -i interface -c path/to/rules.conf -l path/to/directoryIdentify