Network Working Group T. Graf
Internet-Draft Swisscom
Intended status: Standards Track J. Quilbeuf
Expires: 6 September 2023 Huawei
A. Huang Feng
INSA-Lyon
5 March 2023
Support of Hostname and Sequencing in YANG Notifications
draft-tgraf-netconf-notif-sequencing-00
Abstract
This document specifies a new YANG module that augment the NETCONF
Event Notification header to support hostname and sequence numbers to
identify from which network node and at which time the message was
published. This allows to recognize loss, delay and reordering
between the publisher and the downstream system storing the message.
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
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on 6 September 2023.
Copyright Notice
Copyright (c) 2023 IETF Trust and the persons identified as the
document authors. All rights reserved.
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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
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 NETCONF Event Notification Header . . . . . . . . 3
3. YANG Module for Event Notifications . . . . . . . . . . . . . 4
3.1. YANG Tree Diagram . . . . . . . . . . . . . . . . . . . . 4
3.2. Full Tree View . . . . . . . . . . . . . . . . . . . . . 4
3.3. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 5
4. Security Considerations . . . . . . . . . . . . . . . . . . . 6
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
5.1. IETF XML Registry . . . . . . . . . . . . . . . . . . . . 7
5.2. YANG Module Name . . . . . . . . . . . . . . . . . . . . 7
6. Operational Considerations . . . . . . . . . . . . . . . . . 7
6.1. SysName Correlation . . . . . . . . . . . . . . . . . . . 7
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 7
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 7
8.1. Normative References . . . . . . . . . . . . . . . . . . 7
8.2. Informative References . . . . . . . . . . . . . . . . . 8
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9
1. Introduction
[RFC5277] describes the NETCONF event notification header using a XML
Schema. In the metadata of the event notification header, only the
eventTime is present indicating at which time the notification
message was published. For other encodings, the same schema is
implemented using a YANG module in [I-D.ahuang-netconf-notif-yang].
Furthermore, in Section 3.7 of [RFC8641], the subscription ID is
added to the "push-update" and "push-change-update" notification
messages allowing to recognize to which xpath or sub-tree the node
was subscribed to.
When the NETCONF event notification message is forwarded from the
receiver to another system, such as a messaging system or a time
series database where the message is stored, 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.
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Today, network operators workaround this impediment by preserving the
transport source IP address and sequence numbers of the publishing
process. However, this implies that this information needs to be
encoded 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 server 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.
By extending the NETCONF Event Notification header with sysName,
which could be an IP address or a DNS domain name, and a sequence
number as described in [RFC9187], the downstream system is not only
able to identify from which network node, subscription, and time the
message was published but also, the order of the published messages.
To correlate network data among different Network Telemetry planes as
described in Section 3.1 of [RFC9232] or among different YANG push
subscription types defined in Section 3.1 of [RFC8641], sysName
describes from which network node the state change was observed or
from when to when the data was accounted. This is essential for
understanding the timely relationship among these different planes
and YANG push subscription types.
2. Extend the NETCONF Event Notification Header
Besides the eventTime described in Section 2.2.1 of [RFC5277] the
following metadata objects are part of a "push-update" and "push-
change-update" notification message.
sysName: Describes the hostname as specified in [RFC1213] from where
the message was published from.
sequenceNumber: Generates a unique sequence number as described in
[RFC9187] for each published message.
Figure 1 provides an example of a "push-change-update" message with
the sysName and sequenceNumber. This "push-change-update" message is
encoded XML [W3C.REC-xml-20081126] over the Network Configuration
Protocol (NETCONF) as per [RFC8640].
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2023-02-04T16:30:11.22Z
example-router
187653
1011
eth0
up
Figure 1: XML Push Example for a subscription-modified
notification message
3. YANG Module for Event Notifications
3.1. YANG Tree Diagram
This ietf-notification-sequencing YANG module augments the ietf-
notification YANG module specified in [I-D.ahuang-netconf-notif-yang]
adding the sysName and the sequenceNumber leaves as described in
Section 2 of this document.
module: ietf-notification-sequencing
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-sequencing augmentation within the ietf-notification.
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module: ietf-notification
structure notification:
+-- eventTime yang:date-and-time
+-- inotifseq:sysName inet:host
+-- inotifseq:sequenceNumber yang:counter32
3.3. YANG Module
file "ietf-notification-sequencing@2023-03-01.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-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
Alex Huang Feng
";
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description
"Defines NETCONF Event Notification structure with the sysName and
the sequenceNumber.
Copyright (c) 2023 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 2023-03-01 {
description
"First revision";
reference
"RFC XXXX: YANG Notifications Sequencing";
}
sx:augment-structure "/inotif:notification" {
leaf sysName {
type inet:host;
mandatory true;
description
"IP address or a DNS domain name from the server from which
the message was published.";
}
leaf sequenceNumber {
type yang:counter32;
mandatory true;
description
"Unique sequence number as described in [RFC3339] for each
published message.";
}
}
}
4. Security Considerations
The security considerations for the NETCONF Event notifications are
described in [RFC5277]. This documents adds no additional security
considerations.
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5. IANA Considerations
5.1. 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.
5.2. 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
6. Operational Considerations
6.1. SysName Correlation
In order to allow data corelationamong 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.
7. 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.
8. References
8.1. 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-01, 3
March 2023, .
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[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,
.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
.
[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
.
[RFC9187] Touch, J., "Sequence Number Extension for Windowed
Protocols", RFC 9187, DOI 10.17487/RFC9187, January 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,
.
8.2. Informative References
[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,
.
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[RFC8640] Voit, E., Clemm, A., Gonzalez Prieto, A., Nilsen-Nygaard,
E., and A. Tripathy, "Dynamic Subscription to YANG Events
and Datastores over NETCONF", RFC 8640,
DOI 10.17487/RFC8640, September 2019,
.
[RFC8641] Clemm, A. and E. Voit, "Subscription to YANG Notifications
for Datastore Updates", RFC 8641, DOI 10.17487/RFC8641,
September 2019, .
[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
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