From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sven-Haegar Koch Subject: Re: Bridge stays down until a port is added Date: Tue, 27 Sep 2011 02:28:42 +0200 (CEST) Message-ID: References: <20110811070659.GA21307@torres.zugschlus.de> <20110811081706.7307e8b2@nehalam.ftrdhcpuser.net> <20110917204257.GA2636@torres.zugschlus.de> <1316550027.1783.102.camel@dcbw.foobar.com> <20110925082504.GA32712@torres.zugschlus.de> <20110926084743.35cb2ccc@nehalam.linuxnetplumber.net> <4E80DA4D.3090404@gmail.com> <20110926130507.1435d76b@nehalam.linuxnetplumber.net> <4E80F8BD.4010401@gmail.com> Mime-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="8323328-94995099-1317083332=:30860" Cc: Stephen Hemminger , Marc Haber , netdev@vger.kernel.org To: =?ISO-8859-15?Q?Nicolas_de_Peslo=FCan?= Return-path: Received: from mail.sdinet.de ([78.47.32.153]:60096 "EHLO mail.sdinet.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752740Ab1I0Aet (ORCPT ); Mon, 26 Sep 2011 20:34:49 -0400 In-Reply-To: <4E80F8BD.4010401@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --8323328-94995099-1317083332=:30860 Content-Type: TEXT/PLAIN; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE On Tue, 27 Sep 2011, Nicolas de Peslo=FCan wrote: > Le 26/09/2011 22:05, Stephen Hemminger a =E9crit : > > On Mon, 26 Sep 2011 22:02:21 +0200 > > Nicolas de Peslo=FCan wrote: > [...] > > > Stephen, > > >=20 > > > What do you think about a generic per-interface option that would cau= se > > > bind() to accept tentative > > > address hold by a particular interface? This of course violate IPv6 > > > principle, but we are talking > > > about interfaces that are unable to do DAD, either permanently or unt= il > > > something happens on the > > > underlying device. > > >=20 > > > echo 1> /sys/class/net/br0/allow_bind_on_tentative_address > > > echo 1> /sys/class/net/dummy0/allow_bind_on_tentative_address > > > echo 1> /sys/class/net/wlan0/allow_bind_on_tentative_address > > > and so on... > > >=20 > > > And we may possibly automatically reset this option to 0 if DAD event= ually > > > causes the address to be > > > considered duplicate. > >=20 > > The issue is that if DAD rejects a duplicate, the socket is dead and > > application is > > out of luck. >=20 > Yes, and this is by design. Setting the option would state "I want to all= ow > early bind(), prior to DAD and I assume the fact that a possible duplicat= e > address will cause the corresponding socket to be dead and so the using > application." How about a setting just completely disabling this=20 duplicate-address-detection crap? I do not want my servers to ever give up servicing a configured IP no=20 matter what else on the network tries to interfere. If there are two machines using the same IP at a moment, then it may not=20 work so great, but both should have all their services up and running,=20 and once the invalid one got disconnected ("switch port down")=20 everything works - not needing to reboot the real one because some=20 daemons were not able to bind their service IPs. c'ya sven-haegar --=20 Three may keep a secret, if two of them are dead. - Ben F. --8323328-94995099-1317083332=:30860--