This quick reference cheat sheet provides various for using netstat command.
All connections on port 80
$ netstat -anp | grep :80
Netstat Help
$ netstat -h
netstat -ltunp — All Listening ports
netstat -ltn — Listening TCP ports
netstat -lun — Listening UDP ports
netstat -lx — Listening Unix ports
netstat -a — All connections
netstat -at — All TCP connections
netstat -au — All UDP connections
netstat -s — Display statistics
netstat -st — Display TCP statistics
netstat -su — Display UDP statistics
netstat -i — Show network interfaces
netstat -ie — Show network interfaces extended info
netstat -r — Show routing table
netstat -rn — Show routing table, don't resolve hosts