Network Working Group A. Lindem Internet-Draft Y. Qu Intended status: Standards Track Cisco Systems Expires: September 22, 2016 March 21, 2016 RIB YANG Data Model draft-acee-rtgwg-yang-rib-extend-01.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 September 22, 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 (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 September 22, 2016 [Page 1] Internet-Draft YANG RIB March 2016 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 next-hop dampening . . . . . . . . . . . . . . . . . 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 . . . . . . . . . . . . . . . . . . . . . . . . . 10 7.1. Normative References . . . . . . . . . . . . . . . . . . 10 7.2. Informative References . . . . . . . . . . . . . . . . . 10 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 September 22, 2016 [Page 2] Internet-Draft YANG RIB March 2016 [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 next-hop dampening A feature "next-hop-dampen" is defined. Implementations that support this feature can enable/disable RIB dampening. 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 September 22, 2016 [Page 3] Internet-Draft YANG RIB March 2016 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:routing-protocols/rt:routing-protocol/ | rt:static-routes/v4ur:ipv4/v4ur:route/v4ur:next-hop/ | v4ur:next-hop-options: +--:(multi-next-hop) +--rw next-hop-entries* [interface address] +--rw interface string +--rw address inet:ipv4-address +--rw preference? uint32 +--rw tag? uint32 augment /rt:routing/rt:routing-protocols/rt:routing-protocol/ | rt:static-routes/v6ur:ipv6/v6ur:route/v6ur:next-hop/ | v6ur:next-hop-options: +--:(multi-next-hop) +--rw next-hop-entries* [interface address] +--rw interface string +--rw address inet:ipv6-address +--rw preference? uint32 +--rw tag? uint32 augment /rt:routing-state/rt:ribs/rt:rib/rt:routes/rt:route: +--ro metric? uint32 +--ro tag? uint32 augment /rt:routing-state/rt:ribs/rt:rib/rt:routes/rt:route/ | rt:next-hop/rt:next-hop-options/rt:outgoing-interface: +--ro metric? uint32 +--ro tag? uint32 +--ro repair-path +--ro interface? if:interface-ref +--ro address? inet:ip-address +--ro metric? uint32 +--ro tag? uint32 augment /rt:routing-state/rt:ribs/rt:rib/rt:routes/rt:route/ | rt:next-hop/rt:next-hop-options/rt:special-next-hop: +--ro metric? uint32 +--ro tag? uint32 +--ro repair-path +--ro interface? if:interface-ref +--ro address? inet:ip-address +--ro metric? uint32 +--ro tag? uint32 Lindem & Qu Expires September 22, 2016 [Page 4] Internet-Draft YANG RIB March 2016 augment /rt:routing-state/rt:ribs/rt:rib/rt:routes/rt:route/ | rt:next-hop/rt:next-hop-options: +--:(multi-paths) +--ro path-entries* +--ro interface? if:interface-ref +--ro address? inet:ip-address +--ro metric? uint32 +--ro tag? uint32 +--ro repair-path +--ro interface? if:interface-ref +--ro address? inet:ip-address +--ro metric? uint32 +--ro tag? uint32 4. RIB YANG Model file "ietf-rib-extension@2016-03-15.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 Lindem & Qu Expires September 22, 2016 [Page 5] Internet-Draft YANG RIB March 2016 "Acee Lindem - acee@cisco.com Yingzhen QU - yiqu@cisco.com"; 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 2016-03-15 { description "* Update to new routing-cfg model. * Added MPLS label forwarding table. "; reference "RFC XXXX: A YANG Data Model for RIB Extensions."; } revision 2015-10-16 { description "Initial revision."; 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 "Address of the next-hop."; } } grouping attributes { description "Common attributes applicable to all paths."; leaf metric { type uint32; description "route metric."; Lindem & Qu Expires September 22, 2016 [Page 6] Internet-Draft YANG RIB March 2016 } leaf tag { type uint32; description "route tag."; } } grouping path-attribute { description "Path attribute grouping."; uses attributes; container repair-path { uses next-hop; uses attributes; description "The IP Fast ReRoute (IPFRR) repair path."; } } augment "/rt:routing/rt:routing-protocols/" + "rt:routing-protocol/rt:static-routes/v4ur:ipv4/" + "v4ur:route/v4ur:next-hop/v4ur:next-hop-options" { description "Augment recursive static route configuration."; case multi-next-hop { description "Multiple next-hop options"; list next-hop-entries { key "interface address"; leaf interface { type string; description "Outgoing interface name."; } leaf address { type inet:ipv4-address; description "Address of the next-hop."; } leaf preference { type uint32; default "1"; description "route preference."; } leaf tag { type uint32; default "0"; Lindem & Qu Expires September 22, 2016 [Page 7] Internet-Draft YANG RIB March 2016 description "route tag."; } description "List of multiple next hops."; } } } augment "/rt:routing/rt:routing-protocols/" + "rt:routing-protocol/rt:static-routes/v6ur:ipv6/" + "v6ur:route/v6ur:next-hop/v6ur:next-hop-options" { description "Augment recursive static route configuration."; case multi-next-hop { description "Multiple next-hop options"; list next-hop-entries { key "interface address"; leaf interface { type string; description "Outgoing interface name."; } leaf address { type inet:ipv6-address; description "Address of the next-hop."; } leaf preference { type uint32; default "1"; description "route preference."; } leaf tag { type uint32; default "0"; description "tag for this path."; } description "List of multipath."; } } } augment "/rt:routing-state/rt:ribs/rt:rib/" + "rt:routes/rt:route" { Lindem & Qu Expires September 22, 2016 [Page 8] Internet-Draft YANG RIB March 2016 description "Augment a route in RIB with tag."; uses attributes; } augment "/rt:routing-state/rt:ribs/rt:rib/" + "rt:routes/rt:route/rt:next-hop/rt:next-hop-options/" + "rt:outgoing-interface" { description "Add more parameters to a path."; uses path-attribute; } augment "/rt:routing-state/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-state/rt:ribs/rt:rib/" + "rt:routes/rt:route/rt:next-hop/rt:next-hop-options" { description "This case augments the 'next-hop-options' in the routing model."; case multi-paths { description "ecmp"; list path-entries { uses next-hop; uses path-attribute; description "List of multipaths."; } } } } Lindem & Qu Expires September 22, 2016 [Page 9] Internet-Draft YANG RIB March 2016 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. 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", draft-ietf-netmod-routing-cfg-21.txt (work in progress), March 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. Lindem & Qu Expires September 22, 2016 [Page 10] Internet-Draft YANG RIB March 2016 [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 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 September 22, 2016 [Page 11]