Re: [Lsr] IPv6 Flow Label QOS marking support for 5-tuple ECMP / LAG / MLAG hash
Gyan Mishra <hayabusagsm@gmail.com> Mon, 30 November 2020 23:39 UTC
Return-Path: <hayabusagsm@gmail.com>
X-Original-To: lsr@ietfa.amsl.com
Delivered-To: lsr@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 9E1CD3A0896 for <lsr@ietfa.amsl.com>; Mon, 30 Nov 2020 15:39:04 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.087
X-Spam-Level:
X-Spam-Status: No, score=-2.087 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, HTML_MESSAGE=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_REMOTE_IMAGE=0.01, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=gmail.com
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 hC7xECz2--PL for <lsr@ietfa.amsl.com>; Mon, 30 Nov 2020 15:39:02 -0800 (PST)
Received: from mail-pg1-x52f.google.com (mail-pg1-x52f.google.com [IPv6:2607:f8b0:4864:20::52f]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 69D643A03F4 for <lsr@ietf.org>; Mon, 30 Nov 2020 15:39:02 -0800 (PST)
Received: by mail-pg1-x52f.google.com with SMTP id f17so73110pge.6 for <lsr@ietf.org>; Mon, 30 Nov 2020 15:39:02 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=InBf3j5ao9pn6HyNPxRaGRC+ILlSzq5M6LVxMpmJ6dk=; b=pXa1GjkwgMNsyU/KgbcapfaaCnl58AbMNo1kABcJoQmPXrnPlROA4pTSDXhCD0alv2 CdxUNuSi4g3iAKatVmFGOB4kdwKMV53XQpiCTX+kItkj+ASBxfg3Z8iV0itm9JTK8pIn fH2ngsxpWL+GYDpEEYI3ksjcZfGoFdSiUS44uyJQaa/kMG7U6oPYLN+98g5fDRaqbsvy bL+ztq2nztWtd2LHagtbF4bQU/ezsN0Fao4lQzEUMaMh2XdFl+HxAzCVVLD0wRKz2/OT pMRVk4VpvtIdzBD/iYkyMUQ2+IAyiKCgvmGCE3AHfDgOxen9qAiy6Tb7NXXIBSRvsuFj C1KA==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=InBf3j5ao9pn6HyNPxRaGRC+ILlSzq5M6LVxMpmJ6dk=; b=mkLKQla0NMLVpcb1rpUuyx1vy4RK3BUdqkgDDeEHC9HKuI7LR30/u/pzOzWedrBE8p p7pxmK3G/7zg4Uv7kZiplHyxLLvvFH6xbEZa1qBbycXcNHlDtJ4SFdKTkK98FniyIGKr T2jtKb+bNERBM+cap/WG9n2+GVGqfsFKKqgrQcJnwqJRNgffyWnVrM5DN6STgGHU1hqD 3fWCQlh/GjM5QFybqG5b/kn0X21MwjEnsIEayMn2j024MnTB+9/uS4H1kyT1rzG41zRP DbuHiEWYApGrHDZ1kn3+XYP3kJH3BPqR+jfjgEW4BzELeAQP5XfMiYzDZ3IJeyqm7fRO VjJw==
X-Gm-Message-State: AOAM532gTjll6umdH9J+4uIRLC0Oj4OsYhCX4stLccRKxrFAW25wFqaI MfD3lQrZHb0ex9Dt2Ahu+s1bwPaIufYyUJR57YXJjARjeoQ=
X-Google-Smtp-Source: ABdhPJwGKYW8wXuAQX88UEiR6jgiIfhq6gTyaK3BSqH0bxgi1SUDQeeAnWbQpVTHL8K59KagT2bRZclUZqLkbicNxuo=
X-Received: by 2002:a63:887:: with SMTP id 129mr3699996pgi.383.1606779541864; Mon, 30 Nov 2020 15:39:01 -0800 (PST)
MIME-Version: 1.0
References: <CABNhwV3FGcEarfQH-SVuCCdgkNJnODwRrLSK3XhefQkt1Pws0A@mail.gmail.com> <6D7A677C-86BC-4A96-8C7B-70B0563631BE@cisco.com> <CABNhwV1h2B5VZNBcZmMT0ysFTCfqnU+nVCS-x01tDR_UUmyDwg@mail.gmail.com> <B48A8996-0E10-4818-81BC-47E1F2141244@cisco.com>
In-Reply-To: <B48A8996-0E10-4818-81BC-47E1F2141244@cisco.com>
From: Gyan Mishra <hayabusagsm@gmail.com>
Date: Mon, 30 Nov 2020 18:32:30 -0500
Message-ID: <CABNhwV1meUxzqWxrL7RzL-zjZ+eq+pkPPoFJger9juiiiDJzzg@mail.gmail.com>
To: "Acee Lindem (acee)" <acee@cisco.com>
Cc: lsr <lsr@ietf.org>
Content-Type: multipart/alternative; boundary="000000000000d3471405b55b83f1"
Archived-At: <https://mailarchive.ietf.org/arch/msg/lsr/ddDyrAbsbwWQAJdNH0sWk1gaIzo>
Subject: Re: [Lsr] IPv6 Flow Label QOS marking support for 5-tuple ECMP / LAG / MLAG hash
X-BeenThere: lsr@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Link State Routing Working Group <lsr.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/lsr>, <mailto:lsr-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/lsr/>
List-Post: <mailto:lsr@ietf.org>
List-Help: <mailto:lsr-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/lsr>, <mailto:lsr-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 30 Nov 2020 23:39:05 -0000
Understood. I think the gap as you stated as far as ECMP hash algorithm for IPv6 is vendor specific implementation which is independent of LSR. This is a vendor implementation question and not a LSR question. Cheers, Gyan On Mon, Nov 30, 2020 at 4:28 PM Acee Lindem (acee) <acee@cisco.com> wrote: > There is nothing in OSPF or IS-IS protocols related to the ECMP > load-balancing with respect to the flow label. RFC 6437 is an IPv6 WG > (predecessor of 6MAN) document. Are you just trying to torment me š > > > > Acee > > > > *From: *Gyan Mishra <hayabusagsm@gmail.com> > *Date: *Monday, November 30, 2020 at 4:23 PM > *To: *Acee Lindem <acee@cisco.com> > *Cc: *lsr <lsr@ietf.org> > *Subject: *Re: [Lsr] IPv6 Flow Label QOS marking support for 5-tuple ECMP > / LAG / MLAG hash > > > > Hi Acee > > > > 6MAN deals with the IPv6 protocol specifications and not routing protocols > in the ECMP load balancing framework. > > > > 6MAN would not have any idea if ISIS or OSPF AFI IPv6 5-tuple ECMP load > balancing is supported and industry direction to support this critical > feature from a IGP perspective. > > > > This question posed is in the context of LSR IGP load balancing framework, > OSPF & ISIS AFI IPv6 use of RFC 6437 for 5-tuple hash ECMP load balancing > for even 50/50 load balancing hash as opposed to router default flow or > session based load balancing. > > > > Any feedback related in this context is much appreciated. > > > > Kind Regards > > > > Gyan > > > > On Mon, Nov 30, 2020 at 3:39 PM Acee Lindem (acee) <acee@cisco.com> wrote: > > Speaking as LSR Co-Chair: > > > > Hi Gyan, > > This is more a discussion for the 6MAN WG. Here is the charter for the LSR > WG: https://datatracker.ietf.org/wg/lsr/about/ > > No need to cross-post to the LSR listā¦ > > Thanks, > > Acee > > > > *From: *Lsr <lsr-bounces@ietf.org> on behalf of Gyan Mishra < > hayabusagsm@gmail.com> > *Date: *Monday, November 30, 2020 at 3:22 PM > *To: *lsr <lsr@ietf.org> > *Subject: *[Lsr] IPv6 Flow Label QOS marking support for 5-tuple ECMP / > LAG / MLAG hash > > > > > > Dear LSR WG experts, > > > > > > Does anyone know if vendors have started or plan to start supporting IPv6 > flow label 5-tuple dscp marking for ECMP hashing. > > > > IPv6 flow label support for ECMP > > > > https://tools.ietf.org/html/rfc6437 > > > > IPv4 has traditionally always utilized recommended BCP of flow based load > balancing due to issues related to out of order and reordering of packets. > Although per packet load balancing is supported by most vendors it is not > recommended due to forwarding plane impact. > > > > This IPv6 flow label feature of 5-tuple hash provides significant > advantages for operators much needed ECMP load balancing entropy as compare > to traditional āflow or sessionā based load balancing which is the case as > well with MPLS entropy label RFC 6790 load balancing contrasted below. > > > > IPv6 flow label has significant benefits for operators deploying SRv6 > which utilizes the IPv6 data plane to now have ānativeā built in ECMP > entropy as part of the protocol as compare to its predecessor IPv4. > > > > This gives SRv6 another significant edge over MPLS predecessor. > > > > Excerpt from RFC 6437: > > > > Forwarding nodes such as routers and load distributors MUST NOT > > depend only on Flow Label values being uniformly distributed. In > > any usage such as a hash key for load distribution, the Flow Label > > bits MUST be combined at least with bits from other sources within > > the packet, so as to produce a constant hash value for each flow > > and a suitable distribution of hash values across flows. > > Typically, the other fields used will be some or all components of > > the usual 5-tuple. In this way, load distribution will still > > occur even if the Flow Label values are poorly distributed. > > > > Although uniformly distributed flow label values are recommended > > below, and will always be helpful for load distribution, it is unsafe > > to assume their presence in the general case, and the use case needs > > to work even if the flow label value is zero. > > > > As a general practice, packet flows should not be reordered, and the > > use of the Flow Label field does not affect this. In particular, a > > Flow label value of zero does not imply that reordering is > > acceptable. > > > > > > Below comparison of IPv6 flow label benefits over MPLS entropy label: > > > > > > ! MPLS Entropy label > > https://tools.ietf.org/html/rfc6790 > > > > > > > > As a comparison to MPLS entropy label, the mpls entropy label reduces the control plane label binding and LFIB forwarding plane data structure by not having a per ECMP path label allocation per FEC by adding an additional entropy label to the label stack. > > > > > > However MPLS entropy label is still uses the traditional flow or session based load balancing algorithm which results in > > uneven load balancing. > > > > > > Kind Regards > > > > Gyan > > > > > > -- > > *Error! Filename not specified.* <http://www.verizon.com/> > > *Gyan Mishra* > > *Network Solutions Architect * > > > > *M 301 502-1347 13101 Columbia Pike *Silver Spring, MD > > > > > > > -- > > [image: Image removed by sender.] <http://www.verizon.com/> > > *Gyan Mishra* > > *Network Solutions Architect * > > > > *M 301 502-1347 13101 Columbia Pike *Silver Spring, MD > > > -- <http://www.verizon.com/> *Gyan Mishra* *Network Solutions A**rchitect * *M 301 502-134713101 Columbia Pike *Silver Spring, MD
- [Lsr] IPv6 Flow Label QOS marking support for 5-tā¦ Gyan Mishra
- Re: [Lsr] IPv6 Flow Label QOS marking support forā¦ Acee Lindem (acee)
- Re: [Lsr] IPv6 Flow Label QOS marking support forā¦ Gyan Mishra
- Re: [Lsr] IPv6 Flow Label QOS marking support forā¦ Gyan Mishra
- Re: [Lsr] IPv6 Flow Label QOS marking support forā¦ Acee Lindem (acee)
- Re: [Lsr] IPv6 Flow Label QOS marking support forā¦ Gyan Mishra