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Message-ID: <83a51e120712191012r64783b7dk56cc4fbcbdd5685c@mail.gmail.com>
Date: Wed, 19 Dec 2007 13:12:41 -0500
From: "James Nichols" <jamesnichols3@gmail.com>
To: "Jan Engelhardt" <jengelh@computergmbh.de>
Subject: Re: After many hours all outbound connections get stuck in SYN_SENT
Cc: "Eric Dumazet" <dada1@cosmosbay.com>, linux-kernel@vger.kernel.org,
       "Linux Netdev List" <netdev@vger.kernel.org>
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> The router could be sooo crappy that it drops all packets from
> TCP streams that have SACK enabled and the client has opened
> 200+ SACK connections previously... something like that?

I don't know, maybe.  My router is a fairly new model Cisco and is
pretty major (i.e. pretty expensive), so it's not just a total piece
of crap.  Plus, I never restart it when I see these issues.  I just
turn tcp_sack off, the problem goes away, and I'm able to renable
tcp_sack a few hours later and it works fine until many hours later
when I see the SYN_SENT problem again.
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