Re: TCP time_wait and port exhaustion for servers

[Ray Soucy <rps () maine edu>]

There is an extra 7 on that number, it was 48194 (was sitting on a
different PC so I typed it instead of copy-paste).

On Wed, Dec 5, 2012 at 1:58 PM, William Herrin <bill () herrin us> wrote:
> On Wed, Dec 5, 2012 at 12:09 PM, Ray Soucy <rps () maine edu> wrote:
> > Like most web traffic, the majority of these connections open and
> > close in under a second.  When we get to a point that there is enough
> > traffic from users behind the proxy to be generating over 500 new
> > outgoing connections per second, sustained, we start having users
> > experience an error where there are no local ports available to Squid
> > to use since they're all tied up in a TIME_WAIT state.
> >
> > Here is an example of netstat totals on a box we're seeing the behavior on:
> >
> > 481947 TIME_WAIT
>
> Stupid question but how does 500 x 60 = 481947?  To have that many
> connections in TIME_WAIT on a 60 second timer, you'd need more like
> 8000 connections per second, wouldn't you?
>
> Regards,
> Bill Herrin
>
>
>
>
> --
> William D. Herrin ................ herrin () dirtside com  bill () herrin us
> 3005 Crane Dr. ...................... Web: <http://bill.herrin.us/>
> Falls Church, VA 22042-3004



-- 
Ray Patrick Soucy
Network Engineer
University of Maine System

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