From mboxrd@z Thu Jan  1 00:00:00 1970
From: Florian Westphal <fw@strlen.de>
Subject: Re: [PATCH -next 0/2] net: allow setting ecn via routing table
Date: Fri, 31 Oct 2014 00:16:37 +0100
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Cc: Florian Westphal <fw@strlen.de>,
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To: Eric Dumazet <eric.dumazet@gmail.com>
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Eric Dumazet <eric.dumazet@gmail.com> wrote:
> On Thu, 2014-10-30 at 23:15 +0100, Florian Westphal wrote:
> 
> > Do you think a fallback to non-ecn for retransmitted syns would help?
> 
> Unfortunately some firewalls are buggy and accept a single SYN per flow.
[..]
> Note that ECN problems are not only contained in SYN packets being
> eventually dropped. You might have a success to establish a flow, and
> later get CE marks for all packets and cwnd converges to 1.

I see. So that makes ecn=1 default a pure fantasy.

Thanks for explaining this.