From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Daniel P. Berrange" Subject: Re: KVM doesn't send an arp announce after live migrating a domain Date: Wed, 25 Aug 2010 12:36:10 +0100 Message-ID: <20100825113610.GG13337@redhat.com> References: <4C74CBB0.7080203@kangaroot.net> <20100825083812.GG10499@redhat.com> <4C74E091.60100@kangaroot.net> <4C74F313.6040604@redhat.com> <20100825105232.GE13337@redhat.com> <4C74F909.8020909@redhat.com> <20100825111511.GF13337@redhat.com> <4C74FEB9.40204@redhat.com> Reply-To: "Daniel P. Berrange" Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Nils Cant , Gleb Natapov , kvm@vger.kernel.org, libvir-list@redhat.com To: Avi Kivity Return-path: Received: from mx1.redhat.com ([209.132.183.28]:14763 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752541Ab0HYLgU (ORCPT ); Wed, 25 Aug 2010 07:36:20 -0400 Content-Disposition: inline In-Reply-To: <4C74FEB9.40204@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Wed, Aug 25, 2010 at 02:30:01PM +0300, Avi Kivity wrote: > On 08/25/2010 02:15 PM, Daniel P. Berrange wrote: > > > >>So it looks like the default config uses the kernel default? If libvirt > >>uses an existing bridge I agree it shouldn't hack it, but if it creates > >>its own can't it use a sensible default? > >That is the NAT virtual network. That one *does* default to a forward > >delay of 0, but since it is NAT, it is fairly useless for migration > >in anycase. If you do 'virsh net-dumpxml default' you should see that > >delay='0' was added > > > >The OP was using bridging rather than NAT though, so this XML example > >doesn't apply. My comments about libvirt not overriding kenrel policy > >for forward delay were WRT full bridging mode, not the NAT mode[1] > > Yes, of course. > > Can't libvirt also create a non-NAT bridge? Looks like it would prevent > a lot of manual work and opportunity for misconfiguration. Yes, it can on latest Fedora/RHEL6, using the netcf library. This is the new 'virsh iface-XXX' command set (and equivalent APIs). I've not updated the docs to cover this functionality yet though. It also does bonding, and vlans, etc Daniel -- |: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://deltacloud.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|