Trace all packets coming on a specific port (via tcpdump)

1# Trace incoming packets
2`apt-get install tcpdump`
3`tcpdump port 514 and '(tcp-syn|tcp-ack)!=0'`
4
5# Send dummy data
6`echo netcat:"Nginx test log" | nc -t -w 1 rsyslog-server-1.dockerapp.io 514`