netdev - Re: missing icmp redirects

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Message-Id: <20140611000613.3fb3c563523b73244d90dc44@qrator.net>
Date:	Wed, 11 Jun 2014 00:06:13 +0400
From:	Dmitry Popov <ixaphire@...tor.net>
To:	Per Jessen <per@...puter.org>
Cc:	Lukas Tribus <luky-37@...mail.com>,
	"netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: Re: missing icmp redirects

On Tue, 10 Jun 2014 20:10:23 +0200
Per Jessen <per@...puter.org> wrote:

> Lukas Tribus wrote:
> >> See complete description here:
> >>
> >> https://bugzilla.kernel.org/show_bug.cgi?id=72561
> >>
> >> Summary - some ICMP redirects seem to be missing.
> >>
> Okay, I have devised a way to reproduce the problem:
> 
> ...

It's probably not a bug, but intended behavior. See ip_rt_send_redirect in 
net/ipv4/route.c. The kernel has a built-in per-source-address limiter for icmp
redirects. 

You can disable it for example with 
echo -1 > /proc/sys/net/ipv4/route/redirect_silence
Though I am not sure if it is ok in wild networks.
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