Network Working Group T. Graf Internet-Draft Swisscom Intended status: Standards Track J. Quilbeuf Expires: 1 January 2025 Huawei A. Huang Feng INSA-Lyon 30 June 2024 Support of Hostname and Sequencing in YANG Notifications draft-tgraf-netconf-notif-sequencing-06 Abstract This document specifies a new YANG module that augments the NETCONF Event Notification header to support the hostname and sequence number to identify from which network node and at which time the message was published. This allows the collector to recognize loss, delay and reordering between the publisher and the downstream system storing the messages. 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 https://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 1 January 2025. Copyright Notice Copyright (c) 2024 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 (https://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 Graf, et al. Expires 1 January 2025 [Page 1] Internet-Draft YANG Notifications Sequencing June 2024 extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Extend the YANG Notification Header . . . . . . . . . . . . . 3 2.1. Extension for NETCONF Event Notifications . . . . . . . . 4 2.2. Extension for YANG-Push . . . . . . . . . . . . . . . . . 5 3. YANG Module for Event Notifications . . . . . . . . . . . . . 7 3.1. YANG Tree Diagram . . . . . . . . . . . . . . . . . . . . 8 3.2. Full Tree View . . . . . . . . . . . . . . . . . . . . . 8 3.3. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 9 4. Implementation Status . . . . . . . . . . . . . . . . . . . . 13 4.1. 6WIND VSR . . . . . . . . . . . . . . . . . . . . . . . . 13 5. Security Considerations . . . . . . . . . . . . . . . . . . . 13 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 6.1. IETF XML Registry . . . . . . . . . . . . . . . . . . . . 13 6.2. YANG Module Name . . . . . . . . . . . . . . . . . . . . 13 6.3. NETCONF Capability URNs Registry . . . . . . . . . . . . 14 7. Operational Considerations . . . . . . . . . . . . . . . . . 14 7.1. SysName Correlation . . . . . . . . . . . . . . . . . . . 14 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 14 9.1. Normative References . . . . . . . . . . . . . . . . . . 14 9.2. Informative References . . . . . . . . . . . . . . . . . 15 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16 1. Introduction NETCONF Event Notifications [RFC5277] and YANG-Push [RFC8641] allow NETCONF [RFC6241] servers and YANG-Push publishers to send notifications to a data collection. In the metadata of the event notification header, only the eventTime is present indicating at which time the notification message was published. For YANG-Push notifications, the subscription ID is added to the "push-update" and "push-change-update" notification messages allowing the YANG-Push receiver to map and recognize which Xpath or subtree is bound to the subscription. When the NETCONF event notification message is forwarded from the receiver to another system, such as a messaging system or a time series database, the transport context is lost since it is not part of the NETCONF event notification message metadata. Therefore, the downstream system is unable to associate the message to the publishing process (the exporting router), nor able to detect message loss or reordering. Graf, et al. Expires 1 January 2025 [Page 2] Internet-Draft YANG Notifications Sequencing June 2024 To correlate network data among different Network Telemetry planes as described in Section 3.1 of [RFC9232] or among different YANG-Push subscription types as defined in Section 3.1 of [RFC8641], a reference to the node streaming the data is needed. This is essential for understanding the timely relationship among these different planes and YANG-Push subscription types. Today, network operators work around this impediment by preserving the transport source IP address and sequence numbers of the publishing process. However, this implies encoding this information in the NETCONF event notification message which impacts the semantic readability of the message in the downstream system. On top of that, the transport source IP address might not represent the management IP address by which the YANG-Push publisher should be known. In other terms, the source-host [RFC6470], which is the "Address of the remote host for the session" might not be the management IP address. To overcome these issues, this document proposes extending the YANG notification header with a sysName, the node's fully-qualified domain name, and a sequence number as described in [RFC9187]. This allows the downstream system to not only be able to identify from which network node, subscription, and time the message was published but also, the order of the published messages. 2. Extend the YANG Notification Header NETCONF Event Notifications [RFC5277] and YANG-Push [RFC8641] uses the same notification header that is described in Section 2.2.1 of [RFC5277]. [I-D.ahuang-netconf-notif-yang] defines how these notifications should be encoded in JSON and CBOR. Besides the eventTime described in Section 2.2.1 of [RFC5277] the following metadata objects are part of a notification message. sysName: Describes the node's fully-qualified domain name according to the 'sysName' object definition in [RFC1213] from where the message was published from. This value is usually configured on the node by the administrator to uniquely identify the node in the network. sequenceNumber: Generates a unique sequence number for each published message by the publisher process. The number counts up at every published notification message as described in [RFC9187]. Graf, et al. Expires 1 January 2025 [Page 3] Internet-Draft YANG Notifications Sequencing June 2024 2.1. Extension for NETCONF Event Notifications The Notification of NETCONF Event Notifications [RFC5277] uses a XML structure that is defined in Section 2.2.1 of [RFC5277]. [RFC5277] also defines the capability "urn:ietf:params:netconf:capability:notification:1.0" allowing a NETCONF client to know that the NETCONF server supports sending notifications. 2.1.1. Notification header An implementation supporting this document extends the notification defined in Section 2.2.1 of [RFC5277] adding a sysName and a sequenceNumber. Two more child nodes within the "notification" container are expected, representing the sysName and the sequenceNumber. An example showing this extension in XML is provided in Figure 1: 2007-07-08T00:10:00Z example-router 187653 state Ethernet0 enabled Figure 1: NETCONF Event Notification message 2.1.2. Capability exchange This document also adds a new capability to NETCONF so that the NETCONF server can notify the support of the sysName and sequenceNumber to the NETCONF client. When the NETCONF server supports this document, the following capability is advertised: urn:ietf:params:netconf:capability:notification-sysname-sequence:1.0 Graf, et al. Expires 1 January 2025 [Page 4] Internet-Draft YANG Notifications Sequencing June 2024 The capability identifier is requested to IANA in Section 6. In the capability exchange between the NETCONF client and server, the server will announce this capability along with the supported capabilities by the server as shown in the example in Figure 2. urn:ietf:params:xml:ns:netconf:base:1.0 urn:ietf:params:netconf:capability:startup:1.0 urn:ietf:params:netconf:capability:notification:1.0 urn:ietf:params:netconf:capability:notification-sysname-sequence:1.0 4 Figure 2: Example of a capability exchange. 2.2. Extension for YANG-Push YANG-Push [RFC8641] uses the same structure defined in [RFC5277]. [RFC5277] defines the structure using XML encoding. For other YANG encodings, [I-D.ahuang-netconf-notif-yang] describes how notifications should be encoded in JSON and CBOR. 2.2.1. YANG-Push Notification header An implementation supporting this document extends the notification defined in Section 4 of [I-D.ahuang-netconf-notif-yang] adding a sysName and a sequenceNumber. Two more child nodes within the "notification" root container are expected, representing the sysName and the sequenceNumber. Figure 3 provides an example of a "push-update" notification with the sysName and sequenceNumber. This examples is encoded in XML [W3C.REC-xml-20081126]. Graf, et al. Expires 1 January 2025 [Page 5] Internet-Draft YANG Notifications Sequencing June 2024 2023-02-04T16:30:11.22Z example-router 187653 1011 eth0 up Figure 3: YANG-Push Notification example encoded in XML When the notifcation is encoded using JSON [RFC7951], the sysName and the sequenceNumber are encoded at root container. An example is shown in Figure 4. { "ietf-notification:notification": { "eventTime": "2023-02-10T08:00:11.22Z", "ietf-notification-sequencing:sysName":"example-router", "ietf-notification-sequencing:sequenceNumber": 187653, "ietf-yang-push:push-update": { "id": 1011, "datastore-contents": { "ietf-interfaces:interfaces": [ { "interface": { "name": "eth0", "oper-status": "up" } } ] } } } } Graf, et al. Expires 1 January 2025 [Page 6] Internet-Draft YANG Notifications Sequencing June 2024 Figure 4: YANG-Push Notification example encoded in JSON When the notification is encoded in CBOR [RFC9254], the sysName and the sequenceNumber are encoded at root container. An example is shown in Figure 5 using CBOR diagnostic notation from Section 3.1 of [RFC9254]. { "ietf-notification:notification": { "eventTime": "2023-02-10T08:00:11.22Z", "ietf-notification-sequencing:sysName":"example-router", "ietf-notification-sequencing:sequenceNumber": 187653, "ietf-yang-push:push-update": { "id": 1011, "datastore-contents": { "ietf-interfaces:interfaces": [ { "interface": { "name": "eth0", "oper-status": "up" } } ] } } } } Figure 5: YANG-Push Notification example in CBOR diagnostic notation. 2.2.2. YANG-Push capabilities YANG-related system capabilites can be discovered by subscribing to the datastore defined in [RFC9196]. This document augments the "ietf-notification-capabilities" defined in Section 5 of [RFC9196] so that the YANG-Push receiver can learn the capabilities defined in this documents throught the datastore. The definition of this YANG augmentation is specified in Section 3. 3. YANG Module for Event Notifications Graf, et al. Expires 1 January 2025 [Page 7] Internet-Draft YANG Notifications Sequencing June 2024 3.1. YANG Tree Diagram This "ietf-notification-sequencing" YANG module augments the "ietf- notification" YANG module specified in Section 5 of [I-D.ahuang-netconf-notif-yang] adding the sysName and the sequenceNumber leaves and augments "ietf-notification-capabilities" defined in [RFC9196] to add a system level capability. module: ietf-notification-sequencing augment /sysc:system-capabilities/notc:subscription-capabilities: +--ro sysname-sequence-supported? notification-support {sysname-sequence}? augment-structure /inotif:notification: +-- sysName inet:host +-- sequenceNumber yang:counter32 3.2. Full Tree View The following is the YANG tree diagram [RFC8340] for the "ietf- notification" structure: module: ietf-notification structure notification: +-- eventTime yang:date-and-time +-- inotifseq:sysName inet:host +-- inotifseq:sequenceNumber yang:counter32 The following YANG tree diagram [RFC8340] is the full tree of the "ietf-notification-capabilities" YANG model: Graf, et al. Expires 1 January 2025 [Page 8] Internet-Draft YANG Notifications Sequencing June 2024 module: ietf-system-capabilities +--ro system-capabilities +--ro datastore-capabilities* [datastore] | +--ro datastore | | -> /yanglib:yang-library/datastore/name | +--ro per-node-capabilities* [] | +--ro (node-selection)? | | +--:(node-selector) | | +--ro node-selector? | | nacm:node-instance-identifier | +--ro notc:subscription-capabilities | +--ro notc:max-nodes-per-update? uint32 | +--ro notc:periodic-notifications-supported? | | notification-support | +--ro (notc:update-period)? | | +--:(notc:minimum-update-period) | | | +--ro notc:minimum-update-period? uint32 | | +--:(notc:supported-update-period) | | +--ro notc:supported-update-period* uint32 | +--ro notc:on-change-supported? | | notification-support {yp:on-change}? | +--ro notc:minimum-dampening-period? uint32 | | {yp:on-change}? | +--ro notc:supported-excluded-change-type* union | {yp:on-change}? +--ro notc:subscription-capabilities +--ro notc:max-nodes-per-update? uint32 +--ro notc:periodic-notifications-supported? | notification-support +--ro (notc:update-period)? | +--:(notc:minimum-update-period) | | +--ro notc:minimum-update-period? uint32 | +--:(notc:supported-update-period) | +--ro notc:supported-update-period* uint32 +--ro notc:on-change-supported? | notification-support {yp:on-change}? +--ro notc:minimum-dampening-period? uint32 | {yp:on-change}? +--ro notc:supported-excluded-change-type* union | {yp:on-change}? +--ro inotifseq:sysname-sequence-supported? notification-support {sysname-sequence}? 3.3. YANG Module The "ietf-notification-sequencing" augments the "ietf-notification" and "ietf-notification-capabilities" YANG modules. Graf, et al. Expires 1 January 2025 [Page 9] Internet-Draft YANG Notifications Sequencing June 2024 file "ietf-notification-sequencing@2023-05-29.yang" module ietf-notification-sequencing { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-notification-sequencing"; prefix inotifseq; import ietf-inet-types { prefix inet; reference "RFC 6991: Common YANG Data Types"; } import ietf-yang-types { prefix yang; reference "RFC 6991: Common YANG Data Types"; } import ietf-notification { prefix inotif; reference "draft-ahuang-netconf-notif-yang: NETCONF Event Notification YANG"; } import ietf-system-capabilities { prefix sysc; reference "RFC 9196: YANG Modules Describing Capabilities for Systems and Datastore Update Notifications"; } import ietf-notification-capabilities { prefix notc; reference "RFC 9196: YANG Modules Describing Capabilities for Systems and Datastore Update Notifications"; } import ietf-yang-structure-ext { prefix sx; reference "RFC 8791: YANG Data Structure Extensions"; } organization "IETF NETCONF (Network Configuration) Working Group"; contact "WG Web: WG List: Authors: Thomas Graf Jean Quilbeuf Graf, et al. Expires 1 January 2025 [Page 10] Internet-Draft YANG Notifications Sequencing June 2024 Alex Huang Feng "; description "Defines NETCONF Event Notification structure with the sysName and the sequenceNumber. Copyright (c) 2024 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 Revised 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; see the RFC itself for full legal notices."; revision 2023-05-29 { description "First revision"; reference "RFC XXXX: YANG Notifications Sequencing"; } feature sysname-sequence { description "This feature indicates that sysName and sequenceNumber are supported in notifications."; } typedef notification-support { type bits { bit config-changes { description "The publisher is capable of sending notifications for 'config true' nodes for the relevant scope and subscription type."; } bit state-changes { description "The publisher is capable of sending notifications for 'config false' nodes for the relevant scope and subscription type."; } } description Graf, et al. Expires 1 January 2025 [Page 11] Internet-Draft YANG Notifications Sequencing June 2024 "Redefition of the type 'notification-support' from 'ietf-notification-capabilities' module to be reusable in other YANG modules. Type for defining whether 'on-change' or 'periodic' notifications are supported for all data nodes, 'config false' data nodes, 'config true' data nodes, or no data nodes. The bits config-changes or state-changes have no effect when they are set for a datastore or for a set of nodes that does not contain nodes with the indicated config value. In those cases, the effect is the same as if no support was declared. One example of this is indicating support for state-changes for a candidate datastore that has no effect."; reference "RFC XXXX: YANG Notifications Sequencing RFC 9196: YANG Modules Describing Capabilities for Systems and Datastore Update Notifications"; } sx:augment-structure "/inotif:notification" { leaf sysName { type inet:host; mandatory true; description "Fully-qualified domain name of the node according to [RFC1213]. This value is usually configured on the node by the administrator to uniquely identify the node in the network."; } leaf sequenceNumber { type yang:counter32; mandatory true; description "Unique sequence number as described in [RFC3339] for each published message."; } } augment "/sysc:system-capabilities/notc:subscription-capabilities" { description "Add system level capabilities"; leaf sysname-sequence-supported { if-feature "sysname-sequence"; type notification-support; description Graf, et al. Expires 1 January 2025 [Page 12] Internet-Draft YANG Notifications Sequencing June 2024 "Specifies whether the publisher supports exporting a sysName and a sequenceNumber in notifications."; reference "RFC XXXX: YANG Notifications Sequencing"; } } } 4. Implementation Status Note to the RFC-Editor: Please remove this section before publishing. 4.1. 6WIND VSR 6WIND implemented this document for a YANG-Push publisher on UDP-based Transport for Configured Subscriptions [I-D.ietf-netconf-udp-notif] in their VSR platform. 5. Security Considerations The security considerations for the NETCONF Event notifications are described in [RFC5277]. This documents adds no additional security considerations. 6. IANA Considerations 6.1. IETF XML Registry This document registers the following URIs in the "IETF XML Registry" [RFC3688]: URI: urn:ietf:params:xml:ns:yang:ietf-notification-sequencing Registrant Contact: The IESG. XML: N/A; the requested URI is an XML namespace. 6.2. YANG Module Name This document registers the following YANG modules in the "YANG Module Names" registry [RFC6020]: name: ietf-notification-sequencing namespace: urn:ietf:params:xml:ns:yang:ietf-notification-sequencing prefix: inotifseq reference: RFC XXXX Graf, et al. Expires 1 January 2025 [Page 13] Internet-Draft YANG Notifications Sequencing June 2024 6.3. NETCONF Capability URNs Registry This document registers the following NETCONF capability in the "Network Configuration Protocol (NETCONF) Capability URNs" registry: Capability: :notification-sysname-sequence:1.0 Capability Identifier: urn:ietf:params:netconf:capability:notification-sysname-sequence:1.0 Reference: RFC XXXX 7. Operational Considerations 7.1. SysName Correlation In order to allow data correlation among BGP Monitoring Protocol (BMP) [RFC7854] and YANG-Push, the same hostname value should be used as described in Section 4.4 of [RFC7854] for the information TLV in the init BMP message type. 8. Acknowledgements The authors would like to thank Rob Wilton, Nick Corran, Pierre Francois, Benoit Claise, Ahmed Elhassany and Ignacio Dominguez Martinez-Casanueva for their review and valuable comments. 9. References 9.1. Normative References [I-D.ahuang-netconf-notif-yang] Feng, A. H., Francois, P., Graf, T., and B. Claise, "YANG model for NETCONF Event Notifications", Work in Progress, Internet-Draft, draft-ahuang-netconf-notif-yang-05, 18 June 2024, . [RFC1213] McCloghrie, K. and M. Rose, "Management Information Base for Network Management of TCP/IP-based internets: MIB-II", STD 17, RFC 1213, DOI 10.17487/RFC1213, March 1991, . [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004, . [RFC5277] Chisholm, S. and H. Trevino, "NETCONF Event Notifications", RFC 5277, DOI 10.17487/RFC5277, July 2008, . Graf, et al. Expires 1 January 2025 [Page 14] Internet-Draft YANG Notifications Sequencing June 2024 [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010, . [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., and A. Bierman, Ed., "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011, . [RFC7951] Lhotka, L., "JSON Encoding of Data Modeled with YANG", RFC 7951, DOI 10.17487/RFC7951, August 2016, . [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, . [RFC8641] Clemm, A. and E. Voit, "Subscription to YANG Notifications for Datastore Updates", RFC 8641, DOI 10.17487/RFC8641, September 2019, . [RFC9187] Touch, J., "Sequence Number Extension for Windowed Protocols", RFC 9187, DOI 10.17487/RFC9187, January 2022, . [RFC9196] Lengyel, B., Clemm, A., and B. Claise, "YANG Modules Describing Capabilities for Systems and Datastore Update Notifications", RFC 9196, DOI 10.17487/RFC9196, February 2022, . [RFC9254] Veillette, M., Ed., Petrov, I., Ed., Pelov, A., Bormann, C., and M. Richardson, "Encoding of Data Modeled with YANG in the Concise Binary Object Representation (CBOR)", RFC 9254, DOI 10.17487/RFC9254, July 2022, . [W3C.REC-xml-20081126] Bray, T., Paoli, J., Sperberg-McQueen, M., Maler, E., and F. Yergeau, "Extensible Markup Language (XML) 1.0 (Fifth Edition)", World Wide Web Consortium Recommendation REC- xml-20081126, November 2008, . 9.2. Informative References Graf, et al. Expires 1 January 2025 [Page 15] Internet-Draft YANG Notifications Sequencing June 2024 [I-D.ietf-netconf-udp-notif] Zheng, G., Zhou, T., Graf, T., Francois, P., Feng, A. H., and P. Lucente, "UDP-based Transport for Configured Subscriptions", Work in Progress, Internet-Draft, draft- ietf-netconf-udp-notif-13, 27 June 2024, . [RFC6470] Bierman, A., "Network Configuration Protocol (NETCONF) Base Notifications", RFC 6470, DOI 10.17487/RFC6470, February 2012, . [RFC7854] Scudder, J., Ed., Fernando, R., and S. Stuart, "BGP Monitoring Protocol (BMP)", RFC 7854, DOI 10.17487/RFC7854, June 2016, . [RFC9232] Song, H., Qin, F., Martinez-Julia, P., Ciavaglia, L., and A. Wang, "Network Telemetry Framework", RFC 9232, DOI 10.17487/RFC9232, May 2022, . Authors' Addresses Thomas Graf Swisscom Binzring 17 CH-8045 Zurich Switzerland Email: thomas.graf@swisscom.com Jean Quilbeuf Huawei Email: jean.quilbeuf@huawei.com Alex Huang Feng INSA-Lyon Lyon France Email: alex.huang-feng@insa-lyon.fr Graf, et al. Expires 1 January 2025 [Page 16]