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 11:27:05 -0400 Message-ID: <48EF7449.4020508@hp.com> References: <48EEA752.6030505@hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Jay Vosburgh , David Miller , YOSHIFUJI Hideaki , Simon Horman , Alex Sidorenko , "netdev@vger.kernel.org" To: Brian Haley Return-path: Received: from g5t0006.atlanta.hp.com ([15.192.0.43]:45455 "EHLO g5t0006.atlanta.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760930AbYJJP1I (ORCPT ); Fri, 10 Oct 2008 11:27:08 -0400 In-Reply-To: <48EEA752.6030505@hp.com> Sender: netdev-owner@vger.kernel.org List-ID: Brian Haley wrote: > Updated to address Vlad's comment about storing the link-local IPv6 > address in the bond/vlan structure, I no longer overwrite the existing > address with a newer one. Also added missed locking for the inet6_dev. > > I don't see any way to address David Steven's comment since there is > currently no NA tunable in the IPv6 code. > > --- > > This patch adds better IPv6 failover support for bonding devices, > especially when in active-backup mode and there are only IPv6 addresses > configured, as reported by Alex Sidorenko. > > - Creates a new file, net/drivers/bonding/bond_ipv6.c, for the > IPv6-specific routines. Both regular bonds and VLANs over bonds > are supported. > > - Adds a new tunable, num_unsol_na, to limit the number of unsolicited > IPv6 Neighbor Advertisements that are sent on a failover event. > Default is 1. > > - Creates two new IPv6 neighbor discovery functions: > > ndisc_build_skb() > ndisc_send_skb() > > These were required to support VLANs since we have to be able to > add the VLAN id to the skb since ndisc_send_na() and friends > shouldn't be asked to do this. These two routines are basically > __ndisc_send() split into two pieces, in a slightly different order. > > - Updates Documentation/networking/bonding.txt and bumps the rev of bond > support to 3.4.0. > > On failover, this new code will generate one packet: > > - An unsolicited IPv6 Neighbor Advertisement, which helps the switch > learn that the address has moved to the new slave. > > Testing has shown that sending just the NA results in pretty good > behavior when in active-back mode, I saw no lost ping packets for example. > > -Brian > > Signed-off-by: Brian Haley > --- > Looks good to me. This provides a nice base that we can build on. -vlad