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To: stable@freebsd.org, "Pete French" <petefrench@ingresso.co.uk>
Subject: Re: Advice on an odd networking problem
References: <E1Xm5Ex-0008RQ-Jm@dilbert.ingresso.co.uk>
Date: Fri, 07 Nov 2014 10:50:04 +0100
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From: "Michael Ross" <gmx@ross.cx>
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On Wed, 05 Nov 2014 19:23:31 +0100, Pete French  
<petefrench@ingresso.co.uk> wrote:

> make some https
> calls to the nginx server on 127.0.0.1 then what we see is that
> pound then stops being able to connect to Apache for a proportion
> of its calls - its returns 503's.

My guess from "https" + "proportion of calls" + "503":
Maybe you run out of random data for ssl connections.
Thus nginx waits for more random data, times out, apache times out -> 503 ?

Michael