Network Working Group A. Lindem Internet-Draft Y. Qu Intended status: Standards Track Cisco Systems Expires: April 19, 2018 October 16, 2017 RIB YANG Data Model draft-acee-rtgwg-yang-rib-extend-05.txt Abstract The Routing Information Base (RIB) is a list of routes and their corresponding administrative data and operational state. The document [ROUTING-CFG] defines the basic building blocks for RIB, and this model augments it to support multiple next-hops (aka, paths) for each route as well as additional attributes. 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 April 19, 2018. Copyright Notice Copyright (c) 2017 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 (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 Lindem & Qu Expires April 19, 2018 [Page 1] Internet-Draft YANG RIB October 2017 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Requirements Notation . . . . . . . . . . . . . . . . . . 2 2. Design of the Model . . . . . . . . . . . . . . . . . . . . . 2 2.1. RIB Tags and Preference . . . . . . . . . . . . . . . . . 3 2.2. Multiple next-hops . . . . . . . . . . . . . . . . . . . 3 2.3. Repair path . . . . . . . . . . . . . . . . . . . . . . . 3 3. RIB Model Tree . . . . . . . . . . . . . . . . . . . . . . . 3 4. RIB YANG Model . . . . . . . . . . . . . . . . . . . . . . . 5 5. Security Considerations . . . . . . . . . . . . . . . . . . . 10 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 7.1. Normative References . . . . . . . . . . . . . . . . . . 11 7.2. Informative References . . . . . . . . . . . . . . . . . 11 Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 11 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11 1. Introduction This document defines a YANG, [YANG], data model which extends the generic data model for RIB by augmenting the ietf-routing model as defined in [ROUTING-CFG]. RIB is a collection of best routes from all routing protocols. Within a protocol routes are selected based on the metrics in use by that protocol, and the protocol install its best routes to RIB. RIB selects the best route by comparing the route preference (aka, administrative distance) of the associated protocol. The augmentations described herein extend the RIB to support multiple paths per route, route metrics, and administrative tags. 1.1. Requirements Notation The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC-KEYWORDS]. 2. Design of the Model The YANG definitions in this document augment the ietf-routing model defined in [ROUTING-CFG], which provides a basis for routing system data model development. Together with modules defined in Lindem & Qu Expires April 19, 2018 [Page 2] Internet-Draft YANG RIB October 2017 [ROUTING-CFG], a generic RIB Yang model is defined to implement and monitor RIB. The models in [ROUTING-CFG] also define the basic configuration and operational state for both IPv4 and IPv6 static routes and this document also provides augmentations for static routes to support multiple next-hop and more next-hop attributes. 2.1. RIB Tags and Preference Individual routes tags will be supported at both the route and next- hop level. A preference per next-hop is also supported for selection of the most prefered reachable static route. 2.2. Multiple next-hops Both Ipv4 and IPv6 static route configuration defined in [ROUTING-CFG] have been augmented with a multi-next-hop option. A static route/prefix can be configured to have multiple next-hops, each with their own tag and route preference. In RIB, a route may have multiple next-hops. They can be either equal cost multiple paths (ECMP), or they may have different metrics. 2.3. Repair path The loop-free alternate (LFA) Fast Reroute (FRR) pre-computes repair paths by routing protocols, and RIB stores the best repair path. A repair path is augmented in RIB operation state for each path. 3. RIB Model Tree A simplified graphical representation of the augmentations described herein is included below. The meaning of the symbols in this diagrams is as follows: o Brackets "[" and "]" enclose list keys. o Curly braces "{" and "}" contain names of optional features that make the corresponding node conditional. o Abbreviations before data node names: "rw" means configuration (read-write), "ro" state data (read-only), "-x" RPC operations, and "-n" notifications. Lindem & Qu Expires April 19, 2018 [Page 3] Internet-Draft YANG RIB October 2017 o Symbols after data node names: "?" means an optional node, "!" a container with presence, and "*" denotes a "list" or "leaf-list". o Parentheses enclose choice and case nodes, and case nodes are also marked with a colon (":"). o Ellipsis ("...") stands for contents of subtrees that are not shown. augment /rt:routing/rt:control-plane-protocols /rt:control-plane-protocol/rt:static-routes /v4ur:ipv4/v4ur:route/v4ur:next-hop /v4ur:next-hop-options/v4ur:simple-next-hop: +--rw preference? uint32 +--rw tag? uint32 augment /rt:routing/rt:control-plane-protocols /rt:control-plane-protocol/rt:static-routes /v4ur:ipv4/v4ur:route/v4ur:next-hop /v4ur:next-hop-options/v4ur:next-hop-list/v4ur:next-hop-list /v4ur:next-hop: +--rw preference? uint32 +--rw tag? uint32 augment /rt:routing/rt:control-plane-protocols /rt:control-plane-protocol/rt:static-routes /v6ur:ipv6/v6ur:route/v6ur:next-hop /v6ur:next-hop-options/v6ur:simple-next-hop: +--rw preference? uint32 +--rw tag? uint32 augment /rt:routing/rt:control-plane-protocols /rt:control-plane-protocol/rt:static-routes /v6ur:ipv6/v6ur:route/v6ur:next-hop /v6ur:next-hop-options/v6ur:next-hop-list/v6ur:next-hop-list /v6ur:next-hop: +--rw preference? uint32 +--rw tag? uint32 augment /rt:routing/rt:ribs/rt:rib/rt:routes/rt:route: +--ro metric? uint32 +--ro tag? uint32 augment /rt:routing/rt:ribs/rt:rib/rt:routes: +--ro repair-route* [id] +--ro id string +--ro next-hop | +--ro outgoing-interface? if:interface-state-ref | +--ro next-hop-address? inet:ip-address +--ro metric? uint32 augment /rt:routing/rt:ribs/rt:rib/rt:routes/rt:route /rt:next-hop/rt:next-hop-options/rt:simple-next-hop: +--ro repair-path? Lindem & Qu Expires April 19, 2018 [Page 4] Internet-Draft YANG RIB October 2017 -> /rt:routing/ribs/rib/routes/repair-route/id augment /rt:routing/rt:ribs/rt:rib/rt:routes/rt:route /rt:next-hop/rt:next-hop-options/rt:special-next-hop: +--ro repair-path? -> /rt:routing/ribs/rib/routes/repair-route/id augment /rt:routing/rt:ribs/rt:rib/rt:routes/rt:route /rt:next-hop/rt:next-hop-options/rt:next-hop-list /rt:next-hop-list/rt:next-hop: +--ro repair-path? -> /rt:routing/ribs/rib/routes/repair-route/id 4. RIB YANG Model file "ietf-rib@2017-10-16.yang" module ietf-rib-extension { namespace "urn:ietf:params:xml:ns:yang:ietf-rib-extension"; prefix rib; import ietf-inet-types { prefix "inet"; } import ietf-interfaces { prefix "if"; } import ietf-routing { prefix "rt"; } import ietf-ipv4-unicast-routing { prefix "v4ur"; } import ietf-ipv6-unicast-routing { prefix "v6ur"; } organization "Cisco Systems 170 West Tasman Drive San Jose, CA 95134-1706 USA"; contact "Acee Lindem - acee@cisco.com Yingzhen QU - yiqu@cisco.com"; Lindem & Qu Expires April 19, 2018 [Page 5] Internet-Draft YANG RIB October 2017 description "This YANG module extends the generic data model for RIB by augmenting the ietf-netmod-routing-cfg model. It is intended that the module will be extended by vendors to define vendor-specific RIB parameters. "; revision 2017-10-16 { description "Initial RFC Version"; reference "RFC XXXX: A YANG Data Model for RIB Extensions."; } /* Groupings */ grouping next-hop { description "Next-hop grouping"; leaf interface { type if:interface-ref; description "Outgoing interface"; } leaf address { type inet:ip-address; description "IPv4 or IPv6 Address of the next-hop"; } } grouping attributes { description "Common attributes applicable to all paths"; leaf metric { type uint32; description "Route metric"; } leaf tag { type uint32; description "Route tag"; } } grouping path-attribute { description "Path attribute grouping"; leaf repair-path { type leafref { path "/rt:routing/rt:ribs/rt:rib/" Lindem & Qu Expires April 19, 2018 [Page 6] Internet-Draft YANG RIB October 2017 + "rt:routes/repair-route/id"; } description "IP Fast ReRoute (IPFRR) repair path, use a path from repair-route list"; } } augment "/rt:routing/rt:control-plane-protocols/" + "rt:control-plane-protocol/rt:static-routes/v4ur:ipv4/" + "v4ur:route/v4ur:next-hop/v4ur:next-hop-options/" + "v4ur:simple-next-hop" { description "Augment 'simple-next-hop' case in IPv4 unicast route."; leaf preference { type uint32; default "1"; description "Route preference - Used to select among multiple static routes with a lower preference next-hop preferred and equal preference paths yielding Equal Cost Multi-Path (ECMP)."; } leaf tag { type uint32; default "0"; description "Route tag"; } } augment "/rt:routing/rt:control-plane-protocols/" + "rt:control-plane-protocol/rt:static-routes/v4ur:ipv4/" + "v4ur:route/v4ur:next-hop/v4ur:next-hop-options/" + "v4ur:next-hop-list/v4ur:next-hop-list/v4ur:next-hop" { description "Augment static route configuration 'next-hop-list'."; leaf preference { type uint32; default "1"; description "Route preference - Used to select among multiple static routes with a lower preference next-hop preferred and equal preference paths yielding Equal Cost Multi-Path (ECMP)."; } leaf tag { type uint32; Lindem & Qu Expires April 19, 2018 [Page 7] Internet-Draft YANG RIB October 2017 default "0"; description "Route tag"; } } augment "/rt:routing/rt:control-plane-protocols/" + "rt:control-plane-protocol/rt:static-routes/v6ur:ipv6/" + "v6ur:route/v6ur:next-hop/v6ur:next-hop-options/" + "v6ur:simple-next-hop" { description "Augment 'simple-next-hop' case in IPv6 unicast route."; leaf preference { type uint32; default "1"; description "Route preference - Used to select among multiple static routes with a lower preference next-hop preferred and equal preference paths yielding Equal Cost Multi-Path (ECMP)."; } leaf tag { type uint32; default "0"; description "Route tag"; } } augment "/rt:routing/rt:control-plane-protocols/" + "rt:control-plane-protocol/rt:static-routes/v6ur:ipv6/" + "v6ur:route/v6ur:next-hop/v6ur:next-hop-options/" + "v6ur:next-hop-list/v6ur:next-hop-list/v6ur:next-hop" { description "Augment static route configuration 'next-hop-list'."; leaf preference { type uint32; default "1"; description "Route preference - Used to select among multiple static routes with a lower preference next-hop preferred and equal preference paths yielding Equal Cost Multi-Path (ECMP)."; } leaf tag { type uint32; default "0"; description "Route tag"; } Lindem & Qu Expires April 19, 2018 [Page 8] Internet-Draft YANG RIB October 2017 } augment "/rt:routing/rt:ribs/rt:rib/" + "rt:routes/rt:route" { description "Augment a route in RIB with tag."; uses attributes; } augment "/rt:routing/rt:ribs/rt:rib/" + "rt:routes" { description "Augment a route with a list of repair-paths."; list repair-route { key "id"; description "A repair-path entry, which can be referenced by a repair-path."; leaf id { type string; description "A unique identifier."; } container next-hop { description "Route's next-hop attribute."; leaf outgoing-interface { type if:interface-state-ref; description "Name of the outgoing interface."; } leaf next-hop-address { type inet:ip-address; description "IP address of the next hop."; } } leaf metric { type uint32; description "Route metric"; } } } augment "/rt:routing/rt:ribs/rt:rib/" Lindem & Qu Expires April 19, 2018 [Page 9] Internet-Draft YANG RIB October 2017 + "rt:routes/rt:route/rt:next-hop/rt:next-hop-options/" + "rt:simple-next-hop" { description "Add more parameters to a path."; uses path-attribute; } augment "/rt:routing/rt:ribs/rt:rib/" + "rt:routes/rt:route/rt:next-hop/rt:next-hop-options/" + "rt:special-next-hop" { description "Add more parameters to a path."; uses path-attribute; } augment "/rt:routing/rt:ribs/rt:rib/" + "rt:routes/rt:route/rt:next-hop/rt:next-hop-options/" + "rt:next-hop-list/rt:next-hop-list/rt:next-hop" { description "This case augments the 'next-hop-options' in the routing model."; uses path-attribute; } } 5. Security Considerations The YANG model augmentations defined herein do not introduce any security issues other than those already discussed in [ROUTING-CFG], and [NETCONF]. If confidentiality is desired, the underlying NETCONF communication should be utilized as described in [NETCONF-SSH]. 6. IANA Considerations This document registers a URI in the IETF XML registry [XML-REGISTRY]. Following the format in RFC 3688, the following registration is requested to be made: URI: urn:ietf:params:xml:ns:yang:ietf-rib Registrant Contact: The IESG. XML: N/A, the requested URI is an XML namespace. Lindem & Qu Expires April 19, 2018 [Page 10] Internet-Draft YANG RIB October 2017 This document registers a YANG module in the YANG Module Names registry [YANG]. name: ietf-acl namespace: urn:ietf:params:xml:ns:yang:ietf-rib prefix: ietf-rib reference: RFC XXXX 7. References 7.1. Normative References [RFC-KEYWORDS] Bradner, S., "Key words for use in RFC's to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [ROUTING-CFG] Lhothka, L. and A. Lindem, "A YANG Data Model for Routing Management", RFC 8022, November 2016. [YANG] Bjorklund, M., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, October 2010. 7.2. Informative References [NETCONF] Enns, R., Bjorklund, M., Schoenwaelder, J., and A. Bierman, "Network Configuration Protocol (NETCONF)", RFC 6241, June 2011. [NETCONF-SSH] Wasserman, M., "Using NETCONF Protocol over Secure Shell (SSH)", RFC 6242, June 2011. [XML-REGISTRY] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, January 2004. Appendix A. Acknowledgments The RFC text was produced using Marshall Rose's xml2rfc tool. The authors wish to thank Les Ginsberg, Krishna Deevi and Suyoung Yoon for their helpful comments and suggestions. Authors' Addresses Lindem & Qu Expires April 19, 2018 [Page 11] Internet-Draft YANG RIB October 2017 Acee Lindem Cisco Systems 301 Midenhall Way Cary, NC 27513 USA Email: acee@cisco.com Yingzhen Qu Cisco Systems 170 West Tasman Drive San Jose, CA 95134 USA Email: yiqu@cisco.com Lindem & Qu Expires April 19, 2018 [Page 12]