Use of BGP for routing in large-scale data centers
draft-ietf-rtgwg-bgp-routing-large-dc-10

The information below is for an old version of the document
Document Type Active Internet-Draft (rtgwg WG)
Authors Petr Lapukhov  , Ariff Premji  , Jon Mitchell 
Last updated 2016-05-31 (latest revision 2016-04-27)
Replaces draft-lapukhov-bgp-routing-large-dc
Stream IETF
Intended RFC status Informational
Formats pdf htmlized (tools) htmlized bibtex
Reviews
Stream WG state Submitted to IESG for Publication
Document shepherd Jeff Tantsura
Shepherd write-up Show (last changed 2016-02-28)
IESG IESG state In Last Call (ends 2016-06-06)
Consensus Boilerplate Yes
Telechat date
Responsible AD Alia Atlas
Send notices to (None)
IANA IANA review state IANA OK - No Actions Needed
Routing Area Working Group                                   P. Lapukhov
Internet-Draft                                                  Facebook
Intended status: Informational                                 A. Premji
Expires: October 29, 2016                                Arista Networks
                                                        J. Mitchell, Ed.
                                                          April 27, 2016

           Use of BGP for routing in large-scale data centers
                draft-ietf-rtgwg-bgp-routing-large-dc-10

Abstract

   Some network operators build and operate data centers that support
   over one hundred thousand servers.  In this document, such data
   centers are referred to as "large-scale" to differentiate them from
   smaller infrastructures.  Environments of this scale have a unique
   set of network requirements with an emphasis on operational
   simplicity and network stability.  This document summarizes
   operational experience in designing and operating large-scale data
   centers using BGP as the only routing protocol.  The intent is to
   report on a proven and stable routing design that could be leveraged
   by others in the industry.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on October 29, 2016.

Copyright Notice

   Copyright (c) 2016 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents

Lapukhov, et al.        Expires October 29, 2016                [Page 1]
Internet-Draft    draft-ietf-rtgwg-bgp-routing-large-dc       April 2016

   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Network Design Requirements . . . . . . . . . . . . . . . . .   4
     2.1.  Bandwidth and Traffic Patterns  . . . . . . . . . . . . .   4
     2.2.  CAPEX Minimization  . . . . . . . . . . . . . . . . . . .   4
     2.3.  OPEX Minimization . . . . . . . . . . . . . . . . . . . .   5
     2.4.  Traffic Engineering . . . . . . . . . . . . . . . . . . .   5
     2.5.  Summarized Requirements . . . . . . . . . . . . . . . . .   5
   3.  Data Center Topologies Overview . . . . . . . . . . . . . . .   6
     3.1.  Traditional DC Topology . . . . . . . . . . . . . . . . .   6
     3.2.  Clos Network topology . . . . . . . . . . . . . . . . . .   7
       3.2.1.  Overview  . . . . . . . . . . . . . . . . . . . . . .   7
       3.2.2.  Clos Topology Properties  . . . . . . . . . . . . . .   8
       3.2.3.  Scaling the Clos topology . . . . . . . . . . . . . .   9
       3.2.4.  Managing the Size of Clos Topology Tiers  . . . . . .  10
   4.  Data Center Routing Overview  . . . . . . . . . . . . . . . .  11
     4.1.  Layer 2 Only Designs  . . . . . . . . . . . . . . . . . .  11
     4.2.  Hybrid L2/L3 Designs  . . . . . . . . . . . . . . . . . .  12
     4.3.  Layer 3 Only Designs  . . . . . . . . . . . . . . . . . .  12
   5.  Routing Protocol Selection and Design . . . . . . . . . . . .  13
     5.1.  Choosing EBGP as the Routing Protocol . . . . . . . . . .  13
     5.2.  EBGP Configuration for Clos topology  . . . . . . . . . .  15
       5.2.1.  EBGP Configuration Guidelines and Example ASN Scheme   15
       5.2.2.  Private Use ASNs  . . . . . . . . . . . . . . . . . .  16
       5.2.3.  Prefix Advertisement  . . . . . . . . . . . . . . . .  17
       5.2.4.  External Connectivity . . . . . . . . . . . . . . . .  18
       5.2.5.  Route Summarization at the Edge . . . . . . . . . . .  19
   6.  ECMP Considerations . . . . . . . . . . . . . . . . . . . . .  19
     6.1.  Basic ECMP  . . . . . . . . . . . . . . . . . . . . . . .  20
     6.2.  BGP ECMP over Multiple ASNs . . . . . . . . . . . . . . .  21
     6.3.  Weighted ECMP . . . . . . . . . . . . . . . . . . . . . .  21
     6.4.  Consistent Hashing  . . . . . . . . . . . . . . . . . . .  22
Show full document text