Count Network connections by state (Linux)
To display a count of all network connections by their state:
$ sudo netstat -ant | awk '{print $6}' | sort | uniq -c | sort -n
1 established)
1 Foreign
2 SYN_SENT
6 LISTEN
62 CLOSING
185 CLOSE_WAIT
311 FIN_WAIT2
498 SYN_RECV
515 LAST_ACK
1882 TIME_WAIT
2869 FIN_WAIT1
5622 ESTABLISHED
Onbviously the top two entries can be ignored. This is very useful for diagnosing tcp stack issues.