Re: [mpls] Two new drafts on (micro-)BFD over MC-LAG interfaces

Jeffrey Haas <jhaas@pfrc.org> Mon, 11 April 2016 17:19 UTC

Return-Path: <jhaas@slice.pfrc.org>
X-Original-To: mpls@ietfa.amsl.com
Delivered-To: mpls@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 872DC12F1EB; Mon, 11 Apr 2016 10:19:16 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.898
X-Spam-Level:
X-Spam-Status: No, score=-2.898 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RP_MATCHES_RCVD=-0.996, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id XhAyYEaGanGJ; Mon, 11 Apr 2016 10:19:15 -0700 (PDT)
Received: from slice.pfrc.org (slice.pfrc.org [67.207.130.108]) by ietfa.amsl.com (Postfix) with ESMTP id 77F6712F1EA; Mon, 11 Apr 2016 10:19:15 -0700 (PDT)
Received: by slice.pfrc.org (Postfix, from userid 1001) id 4AE8B1E83B; Mon, 11 Apr 2016 13:23:32 -0400 (EDT)
Date: Mon, 11 Apr 2016 13:23:32 -0400
From: Jeffrey Haas <jhaas@pfrc.org>
To: Greg Mirsky <gregimirsky@gmail.com>
Message-ID: <20160411172332.GA22064@pfrc.org>
References: <7347100B5761DC41A166AC17F22DF11221A3CCED@eusaamb103.ericsson.se> <F73A3CB31E8BE34FA1BBE3C8F0CB2AE28C1F040F@SZXEMA510-MBX.china.huawei.com> <CAG1kdojp7Km16YDiwjvPKwRNjbvBWOkqpccRsEDCn8Q8BuV0Qg@mail.gmail.com> <7347100B5761DC41A166AC17F22DF11221A40584@eusaamb103.ericsson.se> <CAG1kdoibVBWsga3K88MGbZAFSbD_2q0efea_8aEKd_hN+CV53w@mail.gmail.com> <7347100B5761DC41A166AC17F22DF11221A40773@eusaamb103.ericsson.se> <D32D53C8.13B077%rrahman@cisco.com> <CA+RyBmW3nDxMphGaJ2eThZ3fs4zvD5D-9kiJBVSTzPoApkWqgA@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CA+RyBmW3nDxMphGaJ2eThZ3fs4zvD5D-9kiJBVSTzPoApkWqgA@mail.gmail.com>
User-Agent: Mutt/1.5.21 (2010-09-15)
Archived-At: <http://mailarchive.ietf.org/arch/msg/mpls/7wEjD0hGawMXZXw2PdAz2LNsLtA>
Cc: "draft-tanmir-rtgwg-bfd-mc-lag-ip@tools.ietf.org" <draft-tanmir-rtgwg-bfd-mc-lag-ip@tools.ietf.org>, "mpls@ietf.org" <mpls@ietf.org>, "mpls-chairs@ietf.org" <mpls-chairs@ietf.org>, "Reshad Rahman \(rrahman\)" <rrahman@cisco.com>, "rtg-bfd@ietf.org" <rtg-bfd@ietf.org>, "rtg-bfd-chairs@ietf.org" <rtg-bfd-chairs@ietf.org>
Subject: Re: [mpls] Two new drafts on (micro-)BFD over MC-LAG interfaces
X-BeenThere: mpls@ietf.org
X-Mailman-Version: 2.1.17
Precedence: list
List-Id: Multi-Protocol Label Switching WG <mpls.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/mpls>, <mailto:mpls-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/mpls/>
List-Post: <mailto:mpls@ietf.org>
List-Help: <mailto:mpls-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/mpls>, <mailto:mpls-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 11 Apr 2016 17:19:16 -0000

Greg,

This is more of a general comment on discussions from the development from
RFC 7130 than any specific comment on your draft.  

On Fri, Apr 08, 2016 at 11:43:18AM -0700, Greg Mirsky wrote:
> yes, link local multicast may be used in MC-LAG scenario. The draft states
> that it MAY be used while the broadcast has SHOULD normative. But we are
> all open to the discussion.

During our discussions across multiple vendors, including some hardware
vendors, it was determined that attempts to exercise the layer 3 mechanisms
would vary significantly across implementations depending on how packets
were encapsulated.  Multicast in particular provided some problematic issues
for us beyond the initial bootstrapping phase of LAG for BFD wherein we
might not have ARP completed.  

My recommendation is to proceed with your drafts with similar caution.  Try
to stay as true to pure IP as possible to best insure the L3 data paths are
exercised across implementations from various vendors.

-- Jeff (speaking as an individual contributor)