From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: [PATCH] make TLLAO option for NA packets configurable Date: Thu, 1 Oct 2009 09:21:00 -0700 Message-ID: <20091001092100.14ea024b@s6510> References: <200910011916.40908.cratiu@ixiacom.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, Octavian Purdila To: Cosmin Ratiu Return-path: Received: from mail.vyatta.com ([76.74.103.46]:52221 "EHLO mail.vyatta.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754566AbZJAQU5 (ORCPT ); Thu, 1 Oct 2009 12:20:57 -0400 In-Reply-To: <200910011916.40908.cratiu@ixiacom.com> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, 1 Oct 2009 19:16:40 +0300 Cosmin Ratiu wrote: > Hello, > > This is a patch that adds a sysctl to control the sending of the Target Link > Layer Address Option (TLLAO) with Neighbor Advertisements responding to > unicast NS. The patch was made for kernel 2.6.7 (yes it is ancient), but the > code is similar with the current kernel and I can rework it if you want it in. > > RFC 2461, page 24 suggests that this option should be included with NAs to > avoid a race with the sender clearing its cache after sending an unicast NS, > but before receiving a NA. > > It seems there are some Juniper routers (MX series) that expect this option to > be included with all NAs. > > Another solution is to always send this option, as it has little overhead. > > Please let me know what you think, > Cosmin. > > Signed-off-by: Cosmin Ratiu > --- //packages/linux_2.6.7/main/src/include/linux/sysctl.h > +++ /home/z/w1/packages/linux_2.6.7/main/src/include/linux/sysctl.h > @@ -444,6 +444,7 @@ > NET_IPV6_IP6FRAG_TIME=23, > NET_IPV6_IP6FRAG_SECRET_INTERVAL=24, > NET_IPV6_MLD_MAX_MSF=25, > + NET_IPV6_NDISC_FORCE_TLLAO=26, Since numbered sysctl values are deprecated, can you use CTL_UNNUMBERED to avoid having to add yet another value?