From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vlad Yasevich Subject: Re: [PATCH v2] bonding: send IPv6 neighbor advertisement on failover Date: Fri, 10 Oct 2008 13:15:08 -0400 Message-ID: <48EF8D9C.2040605@hp.com> References: <29444.1223654036@death.nxdomain.ibm.com> <48EF7CFF.4050405@hp.com> <48EF82D2.6030008@hp.com> <1223657772.10489.5.camel@w-sridhar2.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Brian Haley , Jay Vosburgh , David Stevens , Alex Sidorenko , David Miller , Simon Horman , "netdev@vger.kernel.org" , netdev-owner@vger.kernel.org, YOSHIFUJI Hideaki To: Sridhar Samudrala Return-path: Received: from g5t0006.atlanta.hp.com ([15.192.0.43]:37749 "EHLO g5t0006.atlanta.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759938AbYJJRPM (ORCPT ); Fri, 10 Oct 2008 13:15:12 -0400 In-Reply-To: <1223657772.10489.5.camel@w-sridhar2.beaverton.ibm.com> Sender: netdev-owner@vger.kernel.org List-ID: Sridhar Samudrala wrote: > On Fri, 2008-10-10 at 12:29 -0400, Vlad Yasevich wrote: >> Brian Haley wrote: >>> Jay Vosburgh wrote: >>>> As a semi-related question, what does IPv6 do if it receives a >>>> gratutitous NA, and finds a duplicate? > > I think Jay was asking about the case where the target address in the NA > matches the address of the receiving interface. The RFCs don't describe > how to handle such a case and leave it to the implementation. Linux logs > a warning message and ignores such NA. > Yes, but in this case, you have duplicate addresses configured. This can happen when subnets merge and isn't really related to bonding driver. In such a case, if we do an NS, it will trigger an NA and we'll end up logging such a warning. If we do an NA, the other end, if it's linux, will log this warning, or deal with it in its own manner. So, it's really a draw. -vlad > Thanks > Sridhar > >>> If a node has an IPv6 neighbor entry and receives an unsolicited NA it >>> will change it's state to stale, forcing a re-lookup on the next >>> transmit. An un-solicited NA will change the state to reachable. >> ^^^^^^^^^^^^ >> >> You probably meant to say "solicited". Unsolicited NAs can only change >> the state to STALE. >> >> Also, the re-lookup will happen on a delay after the transmit. >> >> -vlad > >