One liner to check out CLOSE_WAIT and TIME_WAIT connection every five seconds while debugging network apps

while true; do netstat -a|grep WAIT|wc -l; sleep 5; done
This has saved me many times while debugging timeout issues to "too many open files" issues. A high number of the order of thousand, indicates that somewhere connection is not being closed properly.
Sample Output

By: adimania
2013-06-19 09:19:41

1 Alternatives + Submit Alt

What Others Think

I suggest "netstat -an" so it won't do any DNS queries for faster calculation on a busy server. while true; do netstat -an|grep WAIT|wc -l; sleep 5; done
nenominal · 401 weeks and 4 days ago
- the construct "while true; do ...; sleep 5; done" can be replaced by the watch command - "grep STRING | wc -l" can be replaced by "grep -c STRING" So a more elegant version is: watch --interval=5 netstat \| grep -c WAIT
jld · 399 weeks and 4 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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