Internet-Draft | YANG Module for IS-IS Reverse Metric | January 2021 |
Hopps | Expires 9 July 2021 | [Page] |
This document defines a YANG module for managing the reverse metric extension to the the intermediate system to intermediate system routeing protocol.¶
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This document defines a YANG module for managing the reverse metric extension to the intermediate system to intermediate system routeing protocol (IS-IS) [RFC8500], [ISO10589]. Please refer to [RFC8500] for the description and definition of the functionality managed by this module.¶
The YANG data model described in this document conforms to the Network Management Datastore Architecture defined in [RFC8342].¶
The following is the YANG tree diagram ([RFC8340]) for the IS-IS reverse metric extension additions.¶
module: ietf-isis-reverse-metric augment /rt:routing/rt:control-plane-protocols /rt:control-plane-protocol/isis:isis: +--rw reverse-metric +--rw enable-receive? boolean augment /rt:routing/rt:control-plane-protocols /rt:control-plane-protocol/isis:isis/isis:interfaces /isis:interface: +--rw reverse-metric +--rw reverse-metric | +--rw metric? isis:wide-metric | +--rw flags | | +--rw whole-lan? boolean | | +--rw allow-unreachable? boolean | +--rw exclude-te-metric? boolean +--rw level-1 | +--rw reverse-metric | +--rw metric? isis:wide-metric | +--rw flags | | +--rw whole-lan? boolean | | +--rw allow-unreachable? boolean | +--rw exclude-te-metric? boolean +--rw level-2 +--rw reverse-metric +--rw metric? isis:wide-metric +--rw flags | +--rw whole-lan? boolean | +--rw allow-unreachable? boolean +--rw exclude-te-metric? boolean augment /rt:routing/rt:control-plane-protocols /rt:control-plane-protocol/isis:isis/isis:interfaces /isis:interface/isis:adjacencies/isis:adjacency: +--ro reverse-metric +--ro metric? isis:wide-metric +--ro flags | +--ro whole-lan? boolean | +--ro allow-unreachable? boolean +--ro te-metric? uint32¶
The following is the YANG module for managing the IS-IS reverse metric functionality defined in [RFC8500]. It imports modules from the following RFCs: [RFC8349], [I-D.ietf-isis-yang-isis-cfg].¶
<CODE BEGINS> file "ietf-isis-reverse-metric@2021-01-05.yang" module ietf-isis-reverse-metric { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-isis-reverse-metric"; prefix isis-rmetric; import ietf-routing { prefix rt; reference "RFC8349: A YANG Data Model for Routing Management (NMDA Version)"; } import ietf-isis { prefix isis; reference "draft-ietf-isis-yang-isis-cfg-42: YANG Data Model for IS-IS Protocol"; } organization "IETF LSR Working Group (LSR)"; contact "WG Web: <https://tools.ietf.org/wg/lsr/> WG List: <mailto:lsr@ietf.org> Author: Christian Hopps <mailto:chopps@chopps.org>"; // RFC Ed.: replace XXXX with actual RFC number and // remove this note. description "This module defines the configuration and operational state for managing the IS-IS reverse metric functionality [RFC8500]. Copyright (c) 2019 IETF Trust and the persons identified as authors of the code. All rights reserved. Redistribution and use in source and binary forms, with or without modification, is permitted pursuant to, and subject to the license terms contained in, the Simplified BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info). This version of this YANG module is part of RFC XXXX (https://tools.ietf.org/html/rfcXXXX); see the RFC itself for full legal notices."; revision 2021-01-05 { description "Initial Revision"; reference "RFC XXXX: YANG IS-IS Reverse Metric"; } grouping reverse-metric-data { description "IS-IS reverse metric data."; leaf metric { type isis:wide-metric; description "The reverse metric value."; reference "RFC8500, Section 2"; } container flags { description "The reverse metric flag values."; leaf whole-lan { type boolean; description "The 'whole LAN' or W-bit. If true then a DIS processing this reverse metric will add the metric value to all the nodes it advertises in the pseudo-node LSP for this interface. Otherwise it will only increment the metric for the advertising node in the pseudo-node LSP for this interface."; reference "RFC8500, Section 2"; } leaf allow-unreachable { type boolean; description "The 'allow-unreachable' or U-bit. If true it allows the neighbor to increment the overall metric up to 2^24-1 rather than the lesser maximum of 2^24-2, and if done will cause traffic to stop using rather than avoid using the interface."; reference "RFC8500, Section 2"; } } } grouping reverse-metric-if-config-data { description "IS-IS reverse metric config data."; container reverse-metric { description "IS-IS reverse metric data."; uses reverse-metric-data; leaf exclude-te-metric { type boolean; default false; description "If true and there is a TE metric defined for this interface then do not send the TE metric sub-TLV in the reverse metric TLV."; reference "RFC8500, Section 3.5"; } } } grouping tlv16-reverse-metric { description "IS-IS reverse metric TLV data."; container reverse-metric { description "IS-IS reverse metric TLV data."; uses reverse-metric-data; leaf te-metric { type uint32; description "The TE metric value from the sub-TLV if present."; reference "RFC8500, Section 3.5"; } } } augment "/rt:routing/rt:control-plane-protocols/" +"rt:control-plane-protocol/" +"isis:isis" { when "derived-from-or-self(../rt:type, 'isis:isis')" { description "This augment is only valid when routing protocol instance type is 'isis'."; } description "The reverse metric configuration for an IS-IS instance."; container reverse-metric { description "Global reverse metric configuration."; leaf enable-receive { type boolean; default false; description "Enable handling of reverse metric announcements from neighbors. By default reverse metric handling is disabled and must be explicitly enabled through this configuration."; } } } augment "/rt:routing/rt:control-plane-protocols/" +"rt:control-plane-protocol/" +"isis:isis/isis:interfaces/isis:interface" { when "derived-from-or-self(../../../rt:type, 'isis:isis')" { description "This augment is only valid when routing protocol instance type is 'isis'."; } description "The reverse metric configuration for an interface."; container reverse-metric { description "Announce a reverse metric to neighbors."; uses reverse-metric-if-config-data; container level-1 { description "Announce a reverse metric to level-1 neighbors."; uses reverse-metric-if-config-data; } container level-2 { description "Announce a reverse metric to level-2 neighbors."; uses reverse-metric-if-config-data; } } } augment "/rt:routing/rt:control-plane-protocols/" +"rt:control-plane-protocol/" +"isis:isis/isis:interfaces/isis:interface/" +"isis:adjacencies/isis:adjacency" { when "derived-from-or-self(../../../../../rt:type, 'isis:isis')" { description "This augment is only valid when routing protocol instance type is 'isis'"; } description "The reverse metric state advertised by an adjacency."; uses tlv16-reverse-metric; } } <CODE ENDS>¶
This document registers a URI in the "IETF XML Registry" [RFC3688]. Following the format in [RFC3688], the following registration has been made:¶
This document registers one YANG module in the "YANG Module Names" registry [RFC6020]. Following the format in [RFC6020], the following registration has been made:¶
The YANG module specified in this document defines a schema for data that is designed to be accessed via network management protocols such as NETCONF [RFC6241] or RESTCONF [RFC8040]. The lowest NETCONF layer is the secure transport layer, and the mandatory-to-implement secure transport is Secure Shell (SSH) [RFC6242]. The lowest RESTCONF layer is HTTPS, and the mandatory-to-implement secure transport is TLS [RFC8446].¶
The NETCONF access control model [RFC8341] provides the means to restrict access for particular NETCONF or RESTCONF users to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and content.¶
The YANG module defined in this document can enable, disable and modify the behavior of metrics used by routing. For the security implications regarding these types of changes consult the [RFC8500] which defines the functionality.¶
There are a number of data nodes defined in this YANG module that are writable/creatable/deletable (i.e., "config true", which is the default). These data nodes may be considered sensitive or vulnerable in some network environments. Write operations (e.g., edit-config) to these data nodes without proper protection can have a negative effect on network operations.¶
These are the subtrees and data nodes and their sensitivity/vulnerability:¶
Under "/rt:routing/rt:control-plane-protocols/" + "rt:control-plane-protocol/isis:isis" - /isis-rmetric:reverse-metric/isis-rmetric:enable-receive¶
Under "/rt:routing/rt:control-plane-protocols/" + "rt:control-plane-protocol/isis:isis/" + "isis:interfaces/isis:interface/" + "isis-rmetric:reverse-metric" - /isis-rmetric:metric - /isis-rmetric:flags/isis-rmetric:whole-lan - /isis-rmetric:flags/isis-rmetric:allow-unreachable - /isis-rmetric:exclude-te-metric¶
Under "/rt:routing/rt:control-plane-protocols/" + "rt:control-plane-protocol/isis:isis/" + "isis:interfaces/isis:interface/" + "isis:level-1/isis-rmetric:reverse-metric" - /isis-rmetric:metric - /isis-rmetric:flags/isis-rmetric:whole-lan - /isis-rmetric:flags/isis-rmetric:allow-unreachable - /isis-rmetric:exclude-te-metric¶
Under "/rt:routing/rt:control-plane-protocols/" + "rt:control-plane-protocol/isis:isis/" + "isis:interfaces/isis:interface/" + "isis:level-2/isis-rmetric:reverse-metric" - /isis-rmetric:metric - /isis-rmetric:flags/isis-rmetric:whole-lan - /isis-rmetric:flags/isis-rmetric:allow-unreachable - /isis-rmetric:exclude-te-metric¶
Some of the readable data nodes in this YANG module may be considered sensitive or vulnerable in some network environments. It is thus important to control read access (e.g., via get, get-config, or notification) to these data nodes. These are the subtrees and data nodes and their sensitivity/vulnerability:¶
All nodes are under the following subtree, so that prefix will be assume for each node description.¶
Under "/rt:routing/rt:control-plane-protocols/" + "rt:control-plane-protocol/isis:isis/" + "isis:interfaces/isis:interface/" + "isis:adjacencies/isis:adjacency/" + "isis-rmetric:reverse-metric" - /isis-rmetric:metric - /isis-rmetric:flags/isis-rmetric:whole-lan - /isis-rmetric:flags/isis-rmetric:allow-unreachable - /isis-rmetric:te-metric¶
Below is an example of XML instance data to enable reverse metric processing.¶
<rt:routing xmlns:rt="urn:ietf:params:xml:ns:yang:ietf-routing" xmlns:isis="urn:ietf:params:xml:ns:yang:ietf-isis" xmlns:isis-rmetric= "urn:ietf:params:xml:ns:yang:ietf-isis-reverse-metric"> <rt:control-plane-protocols> <rt:control-plane-protocol> <rt:type>isis:isis</rt:type> <rt:name>default</rt:name> <isis:isis> <isis:area-address>00</isis:area-address> <isis-rmetric:reverse-metric> <isis-rmetric:enable-receive>true</isis-rmetric:enable-receive> </isis-rmetric:reverse-metric> </isis:isis> </rt:control-plane-protocol> </rt:control-plane-protocols> </rt:routing>
Below is an example of XML instance data for the ietf-isis-reverse-metric module.¶
<if:interfaces xmlns:if="urn:ietf:params:xml:ns:yang:ietf-interfaces" xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type"> <if:interface> <if:name>eth0</if:name> <if:type>ianaift:ethernetCsmacd</if:type> </if:interface> </if:interfaces> <rt:routing xmlns:rt="urn:ietf:params:xml:ns:yang:ietf-routing" xmlns:isis="urn:ietf:params:xml:ns:yang:ietf-isis" xmlns:isis-rmetric= "urn:ietf:params:xml:ns:yang:ietf-isis-reverse-metric"> <rt:control-plane-protocols> <rt:control-plane-protocol> <rt:type>isis:isis</rt:type> <rt:name>default</rt:name> <isis:isis> <isis:area-address>00</isis:area-address> <isis:interfaces> <isis:interface> <isis:name>eth0</isis:name> <isis-rmetric:reverse-metric> <isis-rmetric:reverse-metric> <isis-rmetric:metric> 65535 </isis-rmetric:metric> </isis-rmetric:reverse-metric> </isis-rmetric:reverse-metric> </isis:interface> </isis:interfaces> </isis:isis> </rt:control-plane-protocol> </rt:control-plane-protocols> </rt:routing>
Below is an example of JSON instance data for the ietf-isis-reverse-metric module.¶
{ "ietf-interfaces:interfaces": { "interface": [ { "name": "eth0", "type": "iana-if-type:ethernetCsmacd" } ] }, "ietf-routing:routing": { "control-plane-protocols": { "control-plane-protocol": [ { "type": "ietf-isis:isis", "name": "default", "ietf-isis:isis": { "area-address": [ "00" ], "interfaces": { "interface": [ { "name": "eth0", "ietf-isis-reverse-metric:reverse-metric": { "level-1": { "reverse-metric": { "metric": 65535, "exclude-te-metric": true } } } } ] } } } ] } } }