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

Gregory Mirsky <gregory.mirsky@ericsson.com> Wed, 13 April 2016 15:49 UTC

Return-Path: <gregory.mirsky@ericsson.com>
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 7FF8912B008; Wed, 13 Apr 2016 08:49:26 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -4.201
X-Spam-Level:
X-Spam-Status: No, score=-4.201 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H2=-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 N79C8PU8eyOZ; Wed, 13 Apr 2016 08:49:24 -0700 (PDT)
Received: from usplmg21.ericsson.net (usplmg21.ericsson.net [198.24.6.65]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id DD6C912D14B; Wed, 13 Apr 2016 08:49:23 -0700 (PDT)
X-AuditID: c6180641-f796f6d000000e1e-60-570e6a5aaae7
Received: from EUSAAHC005.ericsson.se (Unknown_Domain [147.117.188.87]) by usplmg21.ericsson.net (Symantec Mail Security) with SMTP id 00.00.03614.A5A6E075; Wed, 13 Apr 2016 17:48:43 +0200 (CEST)
Received: from EUSAAMB103.ericsson.se ([147.117.188.120]) by EUSAAHC005.ericsson.se ([147.117.188.87]) with mapi id 14.03.0248.002; Wed, 13 Apr 2016 11:49:22 -0400
From: Gregory Mirsky <gregory.mirsky@ericsson.com>
To: Glen Kent <glen.kent@gmail.com>
Thread-Topic: Two new drafts on (micro-)BFD over MC-LAG interfaces
Thread-Index: AdGOvsdErg6+dntrQsqNMvPnP9/byACNIV+ZABt/KgAADGd7oAANpwaAAAYagaD//+aOgIAAJa0AgASgtgD//lcisIAEhjSAgAAYQ7A=
Date: Wed, 13 Apr 2016 15:49:21 +0000
Message-ID: <7347100B5761DC41A166AC17F22DF11221A4498F@eusaamb103.ericsson.se>
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> <20160411172332.GA22064@pfrc.org> <7347100B5761DC41A166AC17F22DF11221A43F14@eusaamb103.ericsson.se> <CAPLq3UPnsT4NJrj2juMZHhStOx6yC2oKr44XWSrAEsVUZ-o5_g@mail.gmail.com>
In-Reply-To: <CAPLq3UPnsT4NJrj2juMZHhStOx6yC2oKr44XWSrAEsVUZ-o5_g@mail.gmail.com>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-originating-ip: [147.117.188.10]
Content-Type: multipart/alternative; boundary="_000_7347100B5761DC41A166AC17F22DF11221A4498Feusaamb103erics_"
MIME-Version: 1.0
X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrLIsWRmVeSWpSXmKPExsUyuXRPuG50Fl+4wb5uTotPDy8xWxzYdJDR Ys+J9ywW36Y9ZbXYf/Atq8W6y6fYLG4tXclqcW1FK7vFktv32C0+/9nG6MDlMeX3RlaPnbPu snssWfKTyeNy71ZWjy+XP7MFsEZx2aSk5mSWpRbp2yVwZeyYMY+t4EgrY8WO+4+ZGhh/NDJ2 MXJySAiYSDw68YsFwhaTuHBvPVsXIxeHkMBRRomvu+4yQjjLGSV6JkJ0sAkYSbzY2MPexcjB ISKgLPHmZgpIDbPACWaJTz1/mUFqhAUcJb7PvwZmiwg4SXy4spgVwi6TmNG9HWwbi4CqxP87 rWA2r4CvxMzGUywQy06zSrR2fmIHSXAKBEqcW3oCbBAj0HnfT61hArGZBcQlbj2ZzwRxtoDE kj3nmSFsUYmXj/+xQthKEpOWnmOFqM+XaD7VxAixTFDi5MwnLBMYRWchGTULSdksJGWzgP5k FtCUWL9LH6JEUWJK90N2CFtDonXOXHZk8QWM7KsYOUqLC3Jy040MNzECI/mYBJvjDsa9vZ6H GAU4GJV4eBMe8IYLsSaWFVfmHmKU4GBWEuEtyuALF+JNSaysSi3Kjy8qzUktPsQozcGiJM7r HfkvTEggPbEkNTs1tSC1CCbLxMEp1cBoY3mtRvzt3Yem8wV0Ztx5wbHD7lq4UPidjY+cK7q+ XXodUCTCNOsSb/xVrRkJ9/VXrE068jlQ7eiJB0fM7j73SLKrlzptImPM+5Jzw32BcubomvyO Fc0Tbczf2k/u2qW38Nbk7OfCSkwr1gkeaD9QwnDT/5Q3w8RQ+5v/rqqqzmtxEwupZO1TYinO SDTUYi4qTgQAvf2/yeACAAA=
Archived-At: <http://mailarchive.ietf.org/arch/msg/mpls/ktSh5SU_ZV9_bf1O22wRt0pkXis>
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: Wed, 13 Apr 2016 15:49:26 -0000

Hi Glen,
thank you for your question. I would not say that GAL label “exists only for the BFD packets”. This special purpose label can be used in infinite number of scenarios, including MC-LAG environment. But I agree, as in the draft-tanmir-rtgwg-bfd-mc-lag-ip, we make certain assumptions about the forwarding engines and whether proper processing of MPLS encapsulated packet may be interpreted as indication of properly functioning Layer 2 and/or Layer 3. Or, what may more important for monitoring link layer, failure detected with MPLS encapsulation may be interpreted as indication of a defect in Layer 2 and/or Layer 3.

                Regards,
                                Greg

From: Glen Kent [mailto:glen.kent@gmail.com]
Sent: Wednesday, April 13, 2016 6:08 AM
To: Gregory Mirsky
Cc: Jeffrey Haas; Greg Mirsky; draft-tanmir-rtgwg-bfd-mc-lag-ip@tools.ietf.org; mpls@ietf.org; mpls-chairs@ietf.org; Alia Atlas (akatlas@gmail.com); Reshad Rahman (rrahman); rtg-bfd@ietf.org; rtg-bfd-chairs@ietf.org
Subject: Re: Two new drafts on (micro-)BFD over MC-LAG interfaces

Gregory,

You are using a special GAL label for BFD packets. This label exists only for the BFD packets.

How can you then claim connectivity for other traffic which will not use this label?

Glen

On Wed, Apr 13, 2016 at 4:18 AM, Gregory Mirsky <gregory.mirsky@ericsson.com<mailto:gregory.mirsky@ericsson.com>> wrote:

Hi Jeff,

thank you for adding more details to the discussions before RFC 7130. We have submitted another draft that proposes to use MPLS encapsulation of BFD control packets over MC-LAG interfaces. Would greatly appreciate reviews, questions and comments on draft-tanmir-rtgwg-bfd-mc-lag-mpls<https://tools.ietf.org/html/draft-tanmir-rtgwg-bfd-mc-lag-mpls-00>00>.



                Regards,

                                Greg



-----Original Message-----
From: Jeffrey Haas [mailto:jhaas@pfrc.org<mailto:jhaas@pfrc.org>]
Sent: Monday, April 11, 2016 10:24 AM
To: Greg Mirsky
Cc: Reshad Rahman (rrahman); draft-tanmir-rtgwg-bfd-mc-lag-ip@tools.ietf.org<mailto:draft-tanmir-rtgwg-bfd-mc-lag-ip@tools.ietf.org>; mpls@ietf.org<mailto:mpls@ietf.org>; mpls-chairs@ietf.org<mailto:mpls-chairs@ietf.org>; Alia Atlas (akatlas@gmail.com<mailto:akatlas@gmail.com>); rtg-bfd@ietf.org<mailto:rtg-bfd@ietf.org>; rtg-bfd-chairs@ietf.org<mailto:rtg-bfd-chairs@ietf.org>
Subject: Re: Two new drafts on (micro-)BFD over MC-LAG interfaces



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)