From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [RFC PATCH] dont create cached routes from ARP requests Date: Wed, 22 Sep 2010 20:34:42 -0700 (PDT) Message-ID: <20100922.203442.233700254.davem@davemloft.net> References: <20100922162209.GA10281@babylon> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: uweber@astaro.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:49607 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751662Ab0IWDeW (ORCPT ); Wed, 22 Sep 2010 23:34:22 -0400 In-Reply-To: <20100922162209.GA10281@babylon> Sender: netdev-owner@vger.kernel.org List-ID: From: Ulrich Weber Date: Wed, 22 Sep 2010 18:22:09 +0200 > Do we really have to cache routes based on ARP requests? > Are there any other reasons than expecting new connections? > > Attached is a patch to skip caching for ARP requests > not related to local IP addresses or ARP proxy. > > Background: At home I have two Internet connections, DSL and Cable. > 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. If you get neighbour table overflows, something is holding a reference to the routing cache entry and/or the neighbour entries those routing cache entries are attached to. If these really are transient entries, they should be trivially garbage collected and not cause any problems at all.