Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753771AbdDNRig (ORCPT ); Fri, 14 Apr 2017 13:38:36 -0400 Received: from mail-pf0-f174.google.com ([209.85.192.174]:34623 "EHLO mail-pf0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751687AbdDNRid (ORCPT ); Fri, 14 Apr 2017 13:38:33 -0400 Date: Fri, 14 Apr 2017 10:38:30 -0700 From: Stephen Hemminger To: Matthias Schiffer Cc: davem@davemloft.net, jbenc@redhat.com, hannes@stressinduktion.org, pshelar@ovn.org, aduyck@mirantis.com, roopa@cumulusnetworks.com, netdev@vger.kernel.org, dev@openvswitch.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next v2 6/6] vxlan: allow multiple VXLANs with same VNI for IPv6 link-local addresses Message-ID: <20170414103830.111a24a8@xeon-e3> In-Reply-To: <95533e3ca4958ba2eca3efcc661713638feea220.1492187126.git.mschiffer@universe-factory.net> References: <95533e3ca4958ba2eca3efcc661713638feea220.1492187126.git.mschiffer@universe-factory.net> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 757 Lines: 18 On Fri, 14 Apr 2017 18:44:46 +0200 Matthias Schiffer wrote: > As link-local addresses are only valid for a single interface, we can allow > to use the same VNI for multiple independent VXLANs, as long as the used > interfaces are distinct. This way, VXLANs can always be used as a drop-in > replacement for VLANs with greater ID space. > > This also extends VNI lookup to respect the ifindex when link-local IPv6 > addresses are used, so using the same VNI on multiple interfaces can > actually work. > > Signed-off-by: Matthias Schiffer Why does this have to be IPv6 specific? What about the case where VXLAN is not bound to an interface? If that is used then that could be a problem.