How to solve the "out of ports" problem?TIME_WAIT reusing seems not work

mowaken nginx-forum at
Wed Mar 9 08:49:39 MSK 2011

I'm using nginx as reverse proxy, and find more than 30k TIME_WAIT state
ports in upstream server. I know my servers are "out of ports" which
discussed here(,
and set both nginx and upstream server to reuse TIME_WAIT and  to
recycle more quickly.

[sysctl -p]
net.ipv4.ip_local_port_range = 1024 65000
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_tw_reuse = 1

But nginx hangs and "connection timed out while connection to upstream
server" error still can be found on nginx error log, when RPS of
upstream is higher than 1000 within 1 minutes. When upstream is Windows,
server will be "out of ports" in seconds.

Any ideas? A connection pool with a waiting queue? Maxim Dounin wrote a
useful module to keep connection with memcached, but why can't it
support Web Server?

Posted at Nginx Forum:,181493,181493#msg-181493

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