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Date: Mon, 5 Sep 2011 08:08:56 +0400
From: Andrey Repin <anrdaemon AT freemail DOT ru>
Reply-To: Andrey Repin <cygwin AT cygwin DOT com>
Message-ID: <124480922.20110905080856@mtu-net.ru>
To: Corinna Vinschen <cygwin AT cygwin DOT com>
Subject: Re: Different error on socket while connecting to a box behind firewall
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Greetings, Corinna Vinschen!

> However, even with this fix, you might not get EHOSTUNREACH either.  In
> my testing, the error returned by the underlying Winsock getsockopt
> function is not WSAEHOSTUNREACH, but WSAETIMEDOUT.  This will be
> translated into ETIMEDOUT == "Connection timed out".

To clarify, and what I think is important to understand, is that the "Host
unreachable" error status could only be triggered by the parent router
returning an explicit "not reachable" reply to a connection attempt. But since
this reply is an ICMP message, many poorly configured intermediate routers,
like home firewalls, could block it and you will get the WSATIMEDOUT for no
apparent answer from the remote host in time.


--
WBR,
Andrey Repin (anrdaemon AT freemail DOT ru) 05.09.2011, <08:04>

Sorry for my terrible english...


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