From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [RFC PATCH] dont create cached routes from ARP requests Date: Thu, 23 Sep 2010 17:05:02 +0200 Message-ID: <1285254302.2509.47.camel@edumazet-laptop> References: <20100922162209.GA10281@babylon> <20100922.203442.233700254.davem@davemloft.net> <20100923144708.GA8037@babylon> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: David Miller , netdev@vger.kernel.org To: Ulrich Weber Return-path: Received: from mail-fx0-f46.google.com ([209.85.161.46]:38038 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754136Ab0IWPFH (ORCPT ); Thu, 23 Sep 2010 11:05:07 -0400 Received: by fxm3 with SMTP id 3so98161fxm.19 for ; Thu, 23 Sep 2010 08:05:06 -0700 (PDT) In-Reply-To: <20100923144708.GA8037@babylon> Sender: netdev-owner@vger.kernel.org List-ID: Le jeudi 23 septembre 2010 =C3=A0 16:47 +0200, Ulrich Weber a =C3=A9cri= t : > On Wed, Sep 22, 2010 at 08:34:42PM -0700, David Miller wrote: > > From: Ulrich Weber > > Date: Wed, 22 Sep 2010 18:22:09 +0200 > >=20 > > > Background: At home I have two Internet connections, DSL and Cabl= e. > > > DSL is the primary uplink while Cable is the secondary. > > > My Cable ISP is flooding me with ARP request from 10.0.0.0/8, > > > which creates routes via the primary uplink. > > > There are thousands of cached routes and after some time > > > I get "Neighbour table overflow" messages. > >=20 > > If you get neighbour table overflows, something is holding a refere= nce > > to the routing cache entry and/or the neighbour entries those routi= ng > > cache entries are attached to. > >=20 > > If these really are transient entries, they should be trivially > > garbage collected and not cause any problems at all. > rt_garbage_collect is not called within rt_intern_hash, > because the call is done within softirq context. >=20 > Forcing the call of rt_garbage_collect didn't help either, > there are no routes freed afterwards... >=20 Please give us more information. grep . /proc/sys/net/ipv4/route/* rtstat -c10 -i1 Thanks