Packet Captures
tcpdump ip + port
tcpdump -nnei port xx and host x.x.x.x (or some variant)
tcpdump icmp
sudo tcpdump -nnei any 'icmp[icmptype] == icmp-echo or icmp[icmptype] == icmp-echoreply' and host 192.168.1.20
IT Notes from various projects because I forget, and hopefully they help you too.
tcpdump -nnei port xx and host x.x.x.x (or some variant)
sudo tcpdump -nnei any 'icmp[icmptype] == icmp-echo or icmp[icmptype] == icmp-echoreply' and host 192.168.1.20