< draft-ietf-netmod-yang-instance-file-format-07.txt   draft-ietf-netmod-yang-instance-file-format-08.txt >
Netmod B. Lengyel Netmod B. Lengyel
Internet-Draft Ericsson Internet-Draft Ericsson
Intended status: Standards Track B. Claise Intended status: Standards Track B. Claise
Expires: August 16, 2020 Cisco Systems, Inc. Expires: September 10, 2020 Cisco Systems, Inc.
February 13, 2020 March 9, 2020
YANG Instance Data File Format YANG Instance Data File Format
draft-ietf-netmod-yang-instance-file-format-07 draft-ietf-netmod-yang-instance-file-format-08
Abstract Abstract
There is a need to document data defined in YANG models when a live There is a need to document data defined in YANG models when a live
server is not available. Data is often needed already at design or server is not available. Data is often needed already at design or
implementation time or needed by groups that do not have a live implementation time or needed by groups that do not have a live
running server available. This document specifies a standard file running server available. This document specifies a standard file
format for YANG instance data, which follows the syntax and semantics format for YANG instance data, which follows the syntax and semantics
of existing YANG models, and annotates it with metadata. of existing YANG models, and annotates it with metadata.
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Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on August 16, 2020. This Internet-Draft will expire on September 10, 2020.
Copyright Notice Copyright Notice
Copyright (c) 2020 IETF Trust and the persons identified as the Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of (https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
skipping to change at page 2, line 16 skipping to change at page 2, line 16
Table of Contents Table of Contents
1. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Principles . . . . . . . . . . . . . . . . . . . . . . . 4 2.1. Principles . . . . . . . . . . . . . . . . . . . . . . . 4
2.2. Delivery of Instance Data . . . . . . . . . . . . . . . . 4 2.2. Delivery of Instance Data . . . . . . . . . . . . . . . . 4
2.3. Data Life cycle . . . . . . . . . . . . . . . . . . . . . 5 2.3. Data Life cycle . . . . . . . . . . . . . . . . . . . . . 5
3. Instance Data File Format . . . . . . . . . . . . . . . . . . 5 3. Instance Data File Format . . . . . . . . . . . . . . . . . . 5
3.1. Specifying the Content Schema . . . . . . . . . . . . . . 7 3.1. Specifying the Content Schema . . . . . . . . . . . . . . 7
3.1.1. Inline Method . . . . . . . . . . . . . . . . . . . . 8 3.1.1. Inline Method . . . . . . . . . . . . . . . . . . . . 7
3.1.2. Simplified-Inline Method . . . . . . . . . . . . . . 8 3.1.2. Simplified-Inline Method . . . . . . . . . . . . . . 8
3.1.3. URI Method . . . . . . . . . . . . . . . . . . . . . 8 3.1.3. URI Method . . . . . . . . . . . . . . . . . . . . . 8
3.2. Examples . . . . . . . . . . . . . . . . . . . . . . . . 8 3.2. Examples . . . . . . . . . . . . . . . . . . . . . . . . 8
4. Backwards Compatibility . . . . . . . . . . . . . . . . . . . 12 4. YANG Instance Data Model . . . . . . . . . . . . . . . . . . 12
5. YANG Instance Data Model . . . . . . . . . . . . . . . . . . 13 4.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 12
5.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 13 4.2. YANG Model . . . . . . . . . . . . . . . . . . . . . . . 13
5.2. YANG Model . . . . . . . . . . . . . . . . . . . . . . . 13 5. Security Considerations . . . . . . . . . . . . . . . . . . . 18
6. Security Considerations . . . . . . . . . . . . . . . . . . . 19 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19 6.1. URI Registration . . . . . . . . . . . . . . . . . . . . 19
7.1. URI Registration . . . . . . . . . . . . . . . . . . . . 19 6.2. YANG Module Name Registration . . . . . . . . . . . . . . 19
7.2. YANG Module Name Registration . . . . . . . . . . . . . . 19 7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 20
8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 20 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 20
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 20 8.1. Normative References . . . . . . . . . . . . . . . . . . 20
9.1. Normative References . . . . . . . . . . . . . . . . . . 20 8.2. Informative References . . . . . . . . . . . . . . . . . 21
9.2. Informative References . . . . . . . . . . . . . . . . . 21
Appendix A. Open Issues . . . . . . . . . . . . . . . . . . . . 22 Appendix A. Open Issues . . . . . . . . . . . . . . . . . . . . 22
Appendix B. Changes between revisions . . . . . . . . . . . . . 22 Appendix B. Changes between revisions . . . . . . . . . . . . . 22
Appendix C. Detailed Use Cases - Non-Normative . . . . . . . . . 24 Appendix C. Backwards Compatibility . . . . . . . . . . . . . . 24
C.1. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . 24 Appendix D. Detailed Use Cases - Non-Normative . . . . . . . . . 24
C.1.1. Use Case 1: Early Documentation of Server D.1. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . 24
D.1.1. Use Case 1: Early Documentation of Server
Capabilities . . . . . . . . . . . . . . . . . . . . 24 Capabilities . . . . . . . . . . . . . . . . . . . . 24
C.1.2. Use Case 2: Preloading Data . . . . . . . . . . . . . 25 D.1.2. Use Case 2: Preloading Data . . . . . . . . . . . . . 26
C.1.3. Use Case 3: Documenting Factory Default Settings . . 25 D.1.3. Use Case 3: Documenting Factory Default Settings . . 26
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 26 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 26
1. Terminology 1. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in BCP
14 RFC 2119 [RFC2119] RFC 8174 [RFC8174] when, and only when, they 14 [RFC2119] [RFC8174] when, and only when, they appear in all
appear in all capitals, as shown here. capitals, as shown here.
Instance Data: A collection of instantiated data nodes. Instance Data: A collection of instantiated data nodes.
Instance Data Set: A named set of data items annotated with metadata Instance Data Set: A named set of data items annotated with metadata
that can be used as instance data in a YANG data tree. that can be used as instance data in a YANG data tree.
Instance Data File: A file containing an instance data set formatted Instance Data File: A file containing an instance data set formatted
according to the rules described in this document. according to the rules described in this document.
Content-schema: A set of YANG modules with their revision, supported Content-schema: A set of YANG modules with their revision, supported
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UC5 Storing diagnostics data UC5 Storing diagnostics data
UC6 Allowing YANG instance data to potentially be carried within UC6 Allowing YANG instance data to potentially be carried within
other IPC message formats other IPC message formats
UC7 Default instance data used as part of a templating solution UC7 Default instance data used as part of a templating solution
UC8 Providing data examples in RFCs or internet drafts UC8 Providing data examples in RFCs or internet drafts
In Appendix C we describe the first three use cases in detail. In Appendix D we describe the first three use cases in detail.
There are many and varied use cases where YANG instance data could be There are many and varied use cases where YANG instance data could be
used. We do not want to limit future uses of instance data sets, so used. We do not want to limit future uses of instance data sets, so
specifying how and when to use YANG instance data is out of scope for specifying how and when to use YANG instance data is out of scope for
this document. It is anticipated that other documents will define this document. It is anticipated that other documents will define
specific use cases. Use cases are listed here only to indicate the specific use cases. Use cases are listed here only to indicate the
need for this work. need for this work.
2.1. Principles 2.1. Principles
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P5 Instance data shall be allowed to contain configuration data, P5 Instance data shall be allowed to contain configuration data,
state data, or a mix of the two. state data, or a mix of the two.
P6 Partial data sets shall be allowed. P6 Partial data sets shall be allowed.
P7 The YANG instance data format shall be usable for any data for P7 The YANG instance data format shall be usable for any data for
which YANG module(s) are defined and available to the reader, which YANG module(s) are defined and available to the reader,
independent of whether the module is actually implemented by a independent of whether the module is actually implemented by a
server. server.
P8 It shall be possible to report the identity of the datastore with
which the instance data set is associated.
2.2. Delivery of Instance Data 2.2. Delivery of Instance Data
Instance data sets that are produced as a result of some sort of Instance data sets that are produced as a result of some sort of
specification or design effort may be available without the need for specification or design effort may be available without the need for
a live server e.g., via download from the vendor's website, or in any a live server e.g., via download from the vendor's website, or in any
other way that product documentation is distributed. other way that product documentation is distributed.
Other instance data sets may be read from or produced by the YANG Other instance data sets may be read from or produced by the YANG
server itself e.g., UC5 documenting diagnostic data. server itself e.g., UC5 documenting diagnostic data.
2.3. Data Life cycle 2.3. Data Life cycle
YANG instance data is always a snapshot of information at a specific A YANG instance data set is created at a specific point of time. If
point of time. If the data changes afterwards, this is not the data changes afterwards, this is not represented in the instance
represented in the instance data set anymore. The current values may data set anymore. The current values may be retrieved at run-time
be retrieved at run-time via NETCONF/RESTCONF or received e.g., in via NETCONF/RESTCONF or received e.g., in YANG-Push notifications.
YANG-Push notifications.
Whether the instance data changes and if so, when and how, should be Whether the instance data changes and if so, when and how, should be
described either in the instance data set's description statement or described either in the instance data set's description statement or
in some other implementation specific manner. in some other implementation specific manner.
3. Instance Data File Format 3. Instance Data File Format
A YANG instance data file MUST contain a single instance data set and A YANG instance data file MUST contain a single instance data set and
no additional data. no additional data.
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a default attribute as defined in [RFC6243] section 6. and in a default attribute as defined in [RFC6243] section 6. and in
[RFC8040] section 4.8.9. [RFC8040] section 4.8.9.
origin metadata as specified in [RFC8526] and [RFC8527] origin metadata as specified in [RFC8526] and [RFC8527]
implementation specific metadata relevant to individual data implementation specific metadata relevant to individual data
nodes. Unknown metadata MUST be ignored by users of instance nodes. Unknown metadata MUST be ignored by users of instance
data, allowing it to be used later for other purposes. data, allowing it to be used later for other purposes.
in the XML format implementation specific XML attributes, unknown
attributes MUST be ignored by users of instance data, allowing
them to be used later for other purposes.
An instance data set MAY contain data for any number of YANG modules; An instance data set MAY contain data for any number of YANG modules;
if needed it MAY carry the complete configuration and state data set if needed it MAY carry the complete configuration and state data set
for a server. Default values SHOULD NOT be included. for a server. Default values SHOULD NOT be included.
Config=true and config=false data MAY be mixed in the instance data Config=true and config=false data MAY be mixed in the instance data
file. file.
Instance data files MAY contain partial data sets. This means Instance data files MAY contain partial data sets. This means
mandatory, min-elements, require-instance=true, must and when mandatory, min-elements, require-instance=true, must and when
constrains MAY be violated. constrains MAY be violated.
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3.1.1. Inline Method 3.1.1. Inline Method
One or more inline-module elements define YANG module(s) used to One or more inline-module elements define YANG module(s) used to
specify the content defining YANG modules. specify the content defining YANG modules.
E.g., ietf-yang-library@2016-06-21 E.g., ietf-yang-library@2016-06-21
The anydata inline-schema carries instance data (conforming to the The anydata inline-schema carries instance data (conforming to the
inline-modules) that actually specifies the content defining YANG inline-modules) that actually specifies the content defining YANG
modules including revision, supported features, deviations and any modules including revision, supported features, deviations and any
relevant additional data (e.g., revision labels). See Section 3.2. relevant additional data (e.g., revision labels
[I-D.verdt-netmod-yang-module-versioning]). See Section 3.2.
3.1.2. Simplified-Inline Method 3.1.2. Simplified-Inline Method
The instance data set contains a list of content defining YANG The instance data set contains a list of content defining YANG
modules including the revision date for each. Usage of this method modules including the revision date for each. Usage of this method
implies that the modules are used without any deviations and with all implies that the modules are used without any deviations and with all
features supported. features supported.
3.1.3. URI Method 3.1.3. URI Method
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The following example is based on "UC1, Documenting Server The following example is based on "UC1, Documenting Server
Capabilities". It provides (a shortened) list of supported YANG Capabilities". It provides (a shortened) list of supported YANG
modules and NETCONF capabilities for a server. It uses the inline modules and NETCONF capabilities for a server. It uses the inline
method to specify the content-schema. method to specify the content-schema.
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<instance-data-set xmlns= <instance-data-set xmlns=
"urn:ietf:params:xml:ns:yang:ietf-yang-instance-data"> "urn:ietf:params:xml:ns:yang:ietf-yang-instance-data">
<name>acme-router-modules</name> <name>acme-router-modules</name>
<yid-version>1</yid-version> <format-version>2020-03-06</format-version>
<content-schema> <content-schema>
<inline-module> <inline-module>
ietf-yang-library@2016-06-21 ietf-yang-library@2016-06-21
</inline-module> </inline-module>
<inline-schema> <inline-schema>
<modules-state <modules-state
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-library"> xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-library">
<module> <module>
<name>ietf-yang-library</name> <name>ietf-yang-library</name>
<revision>2016-06-21</revision> <revision>2016-06-21</revision>
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The following example is based on "UC2, Preloading Default The following example is based on "UC2, Preloading Default
Configuration". It provides a (shortened) default rule set for a Configuration". It provides a (shortened) default rule set for a
read-only operator role. It uses the inline method for specifying read-only operator role. It uses the inline method for specifying
the content-schema. the content-schema.
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<instance-data-set xmlns= <instance-data-set xmlns=
"urn:ietf:params:xml:ns:yang:ietf-yang-instance-data"> "urn:ietf:params:xml:ns:yang:ietf-yang-instance-data">
<name>read-only-acm-rules</name> <name>read-only-acm-rules</name>
<yid-version>1</yid-version> <format-version>2020-03-06</format-version>
<content-schema> <content-schema>
<inline-module>ietf-yang-library@2019-01-04</inline-module> <inline-module>ietf-yang-library@2019-01-04</inline-module>
<inline-schema> <inline-schema>
<yang-library <yang-library
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-library"> xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-library">
<module-set> <module-set>
<name>all</name> <name>all</name>
<module> <module>
<name>ietf-netconf-acm</name> <name>ietf-netconf-acm</name>
<revision>2012-02-22</revision> <revision>2012-02-22</revision>
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The following example is based on UC5 Storing diagnostics data. An The following example is based on UC5 Storing diagnostics data. An
instance data set is produced by the server every 15 minutes that instance data set is produced by the server every 15 minutes that
contains statistics about NETCONF. As a new set is produced contains statistics about NETCONF. As a new set is produced
periodically many times a day a revision-date would be useless; periodically many times a day a revision-date would be useless;
instead a timestamp is included. instead a timestamp is included.
{ {
"ietf-yang-instance-data:instance-data-set": { "ietf-yang-instance-data:instance-data-set": {
"name": "acme-router-netconf-diagnostics", "name": "acme-router-netconf-diagnostics",
"yid-version": "1", "format-version": "2020-03-06",
"content-schema": { "content-schema": {
"same-schema-as-file": "file:///acme-diagnostics-schema.json", "same-schema-as-file": "file:///acme-diagnostics-schema.json",
}, },
"timestamp": "2018-01-25T17:00:38Z", "timestamp": "2018-01-25T17:00:38Z",
"description": "description":
"NETCONF statistics", "NETCONF statistics",
"content-data": { "content-data": {
"ietf-netconf-monitoring:netconf-state": { "ietf-netconf-monitoring:netconf-state": {
"statistics": { "statistics": {
"netconf-start-time ": "2018-12-05T17:45:00Z", "netconf-start-time ": "2018-12-05T17:45:00Z",
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"out-notifications": "39007" "out-notifications": "39007"
} }
} }
} }
} }
} }
Figure 3: JSON Instance Data File example - UC5 Storing diagnostics Figure 3: JSON Instance Data File example - UC5 Storing diagnostics
data data
4. Backwards Compatibility 4. YANG Instance Data Model
The concept of backwards compatibility and what changes are backwards
compatible are not defined for instance data sets as it is highly
dependent on the specific use case and the content-schema.
For instance data that is the result of a design or specification
activity, some changes that may be good to avoid are listed. YANG
uses the concept of managed entities identified by key values; if the
connection between the represented entity and the key value is not
preserved during an update, this may lead to problems.
o If the key value of a list entry that represents the same managed
entity as before is changed, the user may mistakenly identify the
list entry as new.
o If the meaning of a list entry is changed, but the key values are
not (e.g., redefining an alarm-type but not changing its alarm-
type-id) the change may not be noticed.
o If the key value of a previously removed list entry is reused for
a different entity, the change may be misinterpreted as
reintroducing the previous entity.
5. YANG Instance Data Model
5.1. Tree Diagram 4.1. Tree Diagram
The following tree diagram [RFC8340] provides an overview of the data The following tree diagram [RFC8340] provides an overview of the data
model. model.
module: ietf-yang-instance-data module: ietf-yang-instance-data
structure instance-data-set: structure instance-data-set:
+--rw name? string +--rw name? string
+--rw yid-version uint8 +--rw format-version string
+--rw content-schema +--rw content-schema
| +--rw (content-schema-spec)? | +--rw (content-schema-spec)?
| +--:(simplified-inline) | +--:(simplified-inline)
| | +--rw module* string | | +--rw module* string
| +--:(inline) {inline-content-schema}? | +--:(inline) {inline-content-schema}?
| | +--rw inline-module* string | | +--rw inline-module* string
| | +--rw inline-schema <anydata> | | +--rw inline-schema <anydata>
| +--:(uri) | +--:(uri)
| +--rw same-schema-as-file? inet:uri | +--rw same-schema-as-file? inet:uri
+--rw description? string +--rw description* string
+--rw contact? string +--rw contact? string
+--rw organization? string +--rw organization? string
+--rw datastore? ds:datastore-ref +--rw datastore? ds:datastore-ref
+--rw revision* [date] +--rw revision* [date]
| +--rw date string | +--rw date string
| +--rw description? string | +--rw description? string
+--rw timestamp? yang:date-and-time +--rw timestamp? yang:date-and-time
+--rw content-data? <anydata> +--rw content-data? <anydata>
5.2. YANG Model 4.2. YANG Model
<CODE BEGINS> file "ietf-yang-instance-data@2019-11-17.yang" This YANG module imports typedefs from [RFC6991], identities from
module ietf-yang-instance-data { [RFC8342] and the "structure" extension from
yang-version 1.1; [I-D.ietf-netmod-yang-data-ext].
namespace "urn:ietf:params:xml:ns:yang:ietf-yang-instance-data";
prefix yid;
import ietf-yang-structure-ext { The YANG data model in this document conforms to the Network
prefix sx; Management Datastore Architecture (NMDA) defined in [RFC8342]
}
import ietf-datastores {
prefix ds;
}
import ietf-inet-types {
prefix inet;
}
import ietf-yang-types {
prefix yang;
}
organization <CODE BEGINS> file "ietf-yang-instance-data@2020-03-06.yang"
"IETF NETMOD Working Group"; module ietf-yang-instance-data {
contact yang-version 1.1;
"WG Web: <https://datatracker.ietf.org/wg/netmodf/> namespace "urn:ietf:params:xml:ns:yang:ietf-yang-instance-data";
WG List: <mailto:netmod@ietf.org> prefix yid;
Author: Balazs Lengyel import ietf-yang-structure-ext {
<mailto:balazs.lengyel@ericsson.com>"; prefix sx;
description }
"The module defines the structure and content of YANG import ietf-datastores {
instance data sets. prefix ds;
}
import ietf-inet-types {
prefix inet;
}
import ietf-yang-types {
prefix yang;
}
The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', organization
'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', "IETF NETMOD Working Group";
'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document contact
are to be interpreted as described in BCP 14 (RFC 2119) "WG Web: <https://datatracker.ietf.org/wg/netmodf/>
(RFC 8174) when, and only when, they appear in all WG List: <mailto:netmod@ietf.org>
capitals, as shown here.
Copyright (c) 2019 IETF Trust and the persons identified as Author: Balazs Lengyel
authors of the code. All rights reserved. <mailto:balazs.lengyel@ericsson.com>";
description
"The module defines the structure and content of YANG
instance data sets.
Redistribution and use in source and binary forms, with or The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL',
without modification, is permitted pursuant to, and subject 'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED',
to the license terms contained in, the Simplified BSD License 'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document
set forth in Section 4.c of the IETF Trust's Legal Provisions are to be interpreted as described in BCP 14 (RFC 2119)
Relating to IETF Documents (RFC 8174) when, and only when, they appear in all
(http://trustee.ietf.org/license-info). capitals, as shown here.
This version of this YANG module is part of RFC XXXX; see Copyright (c) 2020 IETF Trust and the persons identified as
the RFC itself for full legal notices."; authors of the code. All rights reserved.
revision 2019-11-17 { Redistribution and use in source and binary forms, with or
description without modification, is permitted pursuant to, and subject
"Initial revision."; to the license terms contained in, the Simplified BSD License
reference set forth in Section 4.c of the IETF Trust's Legal Provisions
"RFC XXXX: YANG Instance Data Format"; Relating to IETF Documents
} (http://trustee.ietf.org/license-info).
feature inline-content-schema { This version of this YANG module is part of RFC XXXX; see
description the RFC itself for full legal notices.";
"This feature indicates that inline content-schema
option is supported.";
}
sx:structure "instance-data-set" { revision 2020-03-06 {
description
"A data structure to define a format for
YANG instance data sets. Consists of meta-data about
the instance data set and the real content-data.";
leaf name {
type string;
description description
"Name of the YANG instance data set."; "Initial revision.";
reference
"RFC XXXX: YANG Instance Data Format";
} }
leaf yid-version {
type uint8; feature inline-content-schema {
mandatory true;
description description
"Version number of the 'YANG Instance Data format'. "This feature indicates that inline content-schema
It MUST contain the value '1' for instance data option is supported.";
based on this specification.";
} }
container content-schema { sx:structure "instance-data-set" {
description description
"The content schema used to create the instance data set"; "A data structure to define a format for
choice content-schema-spec { YANG instance data sets. Consists of meta-data about
the instance data set and the real content-data.";
leaf name {
type string;
description description
"Specification of the content-schema"; "Name of the YANG instance data set.";
case simplified-inline { }
leaf-list module { leaf format-version {
type string ; type string;
description default "2020-03-06";
"The list of content defining YANG modules. description
The value SHALL start with the module name. "Version of the 'YANG Instance Data format'.
If the module contains a revision statement the
revision date SHALL be included in the leaf-list
entry.
If other methods (e.g., revision-label) are
defined to identify individual module revisions
those MAY be used instead of using a revision date.
E.g., ietf-yang-library@2016-06-21 It SHALL contain the revision date of the
ietf-yang-instance-data module used when creating the
instance data set in a YYYY-MM-DD format";
}
container content-schema {
description
"The content schema used to create the instance data set";
choice content-schema-spec {
description
"Specification of the content-schema";
case simplified-inline {
leaf-list module {
type string;
description
"The list of content defining YANG modules.
Usage of this leaf-list implies the modules are The value SHALL start with the module name.
used without any deviations and with all features If the module contains a revision statement the
supported. Multiple revisions of the same module revision date SHALL be included in the leaf-list
MUST NOT be specified."; entry. If other methods (e.g., revision-label) are
defined to identify individual module revisions
those MAY be used instead of using a revision date.
E.g., ietf-yang-library@2016-06-21
Usage of this leaf-list implies the modules are
used without any deviations and with all features
supported. Multiple revisions of the same module
MUST NOT be specified.";
}
} }
} case inline {
case inline { if-feature "inline-content-schema";
if-feature inline-content-schema; leaf-list inline-module {
leaf-list inline-module { type string;
type string ; min-elements 1;
min-elements 1; ordered-by user;
ordered-by user; description
description "Indicates that content defining YANG modules
"Indicates that content defining YANG modules are specified inline.
are specified inline.
The value SHALL start with the module name.
If the module contains a revision statement the
revision date SHALL be included in the leaf-list
entry.
If other methods (e.g., revision-label) are
defined to identify individual module revisions
those MAY be used instead of using a revision date.
E.g., ietf-yang-library@2016-06-21 The value SHALL start with the module name.
If the module contains a revision statement the
revision date SHALL be included in the leaf-list
entry. If other methods (e.g., revision-label) are
defined to identify individual module revisions
those MAY be used instead of using a revision date.
The first item is either ietf-yang-library or some other E.g., ietf-yang-library@2016-06-21
YANG module that contains a list of YANG modules with
their name, revision-date, supported-features, and
deviations.
As some versions of ietf-yang-library MAY contain
different module-sets for different datastores, if
multiple module-sets are included, the instance data
set's meta-data MUST contain the datastore information
and instance data for the ietf-yang-library MUST also
contain information specifying the module-set for the
relevant datastore.
Subsequent items MAY specify YANG modules augmenting the The first item is either ietf-yang-library or some
first module with useful data (e.g., revision label)."; other YANG module that contains a list of YANG modules
} with their name, revision-date, supported-features,
anydata inline-schema { and deviations. The usage of
mandatory true; ietf-yang-library@2019-01-04 MUST be supported.
description Using other modules, module versions MAY also be
"Instance data corresponding to the YANG modules supported.
specified in the inline-module nodes defining the set
of content defining YANG modules for this As some versions of ietf-yang-library MAY contain
instance-data-set."; different module-sets for different datastores, if
multiple module-sets are included, the instance data
set's meta-data MUST contain the datastore information
and instance data for the ietf-yang-library MUST also
contain information specifying the module-set for the
relevant datastore.
Subsequent items MAY specify YANG modules augmenting
the first module with useful data
(e.g., revision label).";
}
anydata inline-schema {
mandatory true;
description
"Instance data corresponding to the YANG modules
specified in the inline-module nodes defining the set
of content defining YANG modules for this
instance-data-set.";
}
} }
} case uri {
case uri { leaf same-schema-as-file {
leaf same-schema-as-file { type inet:uri;
type inet:uri; description
description "A reference to another YANG instance data file.
"A reference to another YANG instance data file. This instance data file uses the same
This instance data file uses the same content schema as the referenced file.";
content schema as the referenced file."; }
} }
} }
} }
} leaf-list description {
leaf-list description { type string;
type string; description
description "Description of the instance data set.";
"Description of the instance data set."; }
} leaf contact {
leaf contact { type string;
type string; description
description "Contact information for the person or
"Contact information for the person or organization to whom queries concerning this
organization to whom queries concerning this instance data set should be sent.";
instance data set should be sent."; }
} leaf organization {
leaf organization { type string;
type string; description
description "Organization responsible for the instance
"Organization responsible for the instance data set.";
data set."; }
} leaf datastore {
leaf datastore { type ds:datastore-ref;
type ds:datastore-ref; description
description "The identity of the datastore with which the
"The identity of the datastore with which the instance data set is associated, e.g., the datastore from
instance data set is associated, e.g., the datastore from where the data was read or the datastore into which the data
where the data was read or the datastore into which the data may be loaded or the datastore which is being documented.
may be loaded or the datastore which is being documented. If a single specific datastore cannot be specified, the
If a single specific datastore cannot be specified, the leaf MUST be absent.
leaf MUST be absent.
If this leaf is absent, then the datastore to which the If this leaf is absent, then the datastore to which the
instance data belongs is undefined."; instance data belongs is undefined.";
} }
list revision { list revision {
key "date"; key "date";
description description
"Instance data sets that are produced as "Instance data sets that are produced as
a result of some sort of specification or design effort a result of some sort of specification or design effort
SHOULD have at least one revision entry. For every SHOULD have at least one revision entry. For every
published editorial change, a new one SHOULD be added published editorial change, a new one SHOULD be added
in front of the revisions sequence so that all in front of the revisions sequence so that all
revisions are in reverse chronological order. revisions are in reverse chronological order.
For instance data sets that are read from For instance data sets that are read from
or produced by a server or otherwise or produced by a server or otherwise
subject to frequent updates or changes, revision subject to frequent updates or changes, revision
SHOULD NOT be present"; SHOULD NOT be present";
leaf date { leaf date {
type string { type string {
pattern '\d{4}-\d{2}-\d{2}'; pattern '\d{4}-\d{2}-\d{2}';
}
description
"Specifies the date the instance data set
was last modified. Formatted as YYYY-MM-DD";
} }
leaf description {
type string;
description
"Description of this revision of the instance data set.";
}
}
leaf timestamp {
type yang:date-and-time;
description description
"Specifies the date the instance data set "The date and time when the instance data set
was last modified. Formatted as YYYY-MM-DD"; was last modified.
For instance data sets that are read from or produced
by a server or otherwise subject to frequent
updates or changes, timestamp SHOULD be present";
} }
leaf description { anydata content-data {
type string;
description description
"Description of this revision of the instance data set."; "Contains the real instance data.
The data MUST conform to the relevant YANG Modules specified
either in the content-schema-spec or in some other
implementation specific manner.";
} }
} }
leaf timestamp {
type yang:date-and-time;
description
"The date and time when the instance data set
was last modified.
For instance data sets that are read from or produced
by a server or otherwise subject to frequent
updates or changes, timestamp SHOULD be present";
}
anydata content-data {
description
"Contains the real instance data.
The data MUST conform to the relevant YANG Modules specified
either in the content-schema-spec or in some other
implementation specific manner.";
}
} }
} <CODE ENDS>
<CODE ENDS>
6. Security Considerations 5. Security Considerations
The YANG module defined in this document is designed as a wrapper The YANG module defined in this document is designed as a wrapper
specifying a format and a metadata header for YANG instance data specifying a format and a metadata header for YANG instance data
defined by the content-schema. The data is designed to be accessed defined by the content-schema. The data is designed to be accessed
as a stored file or over any file access method or protocol. as a stored file or over any file access method or protocol.
The document does not specify any method to influence the behavior of The document does not specify any method to influence the behavior of
a server. a server.
Instance data files may contain sensitive data. Instance data files may contain sensitive data.
skipping to change at page 19, line 31 skipping to change at page 19, line 24
of the instance data, instance data files MAY need to be handled in a of the instance data, instance data files MAY need to be handled in a
secure way. The same kind of handling should be applied, that would secure way. The same kind of handling should be applied, that would
be needed for the result of a read operation returning the same data. be needed for the result of a read operation returning the same data.
Instance data files should be protected against modification or Instance data files should be protected against modification or
unauthorized access using normal file handling mechanisms. Care unauthorized access using normal file handling mechanisms. Care
should be taken, when copying the original files or providing file should be taken, when copying the original files or providing file
access for additional users, not to reveal information access for additional users, not to reveal information
unintentionally. unintentionally.
7. IANA Considerations 6. IANA Considerations
This document registers one URI and one YANG module. This document registers one URI and one YANG module.
7.1. URI Registration 6.1. URI Registration
This document registers one URI in the IETF XML registry [RFC3688]. This document registers one URI in the IETF XML registry [RFC3688].
Following the format in RFC 3688, the following registration is Following the format in RFC 3688, the following registration is
requested to be made: requested to be made:
URI: urn:ietf:params:xml:ns:yang:ietf-yang-instance-data URI: urn:ietf:params:xml:ns:yang:ietf-yang-instance-data
Registrant Contact: The IESG. Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace. XML: N/A, the requested URI is an XML namespace.
7.2. YANG Module Name Registration 6.2. YANG Module Name Registration
This document registers one YANG module in the YANG Module Names This document registers one YANG module in the YANG Module Names
registry [RFC6020]. registry [RFC6020].
name: ietf-yang-instance-data name: ietf-yang-instance-data
namespace: urn:ietf:params:xml:ns:yang:ietf-yang-instance-data namespace: urn:ietf:params:xml:ns:yang:ietf-yang-instance-data
prefix: yid prefix: yid
reference: RFC XXXX reference: RFC XXXX
8. Acknowledgments 7. Acknowledgments
For their valuable comments, discussions, and feedback, we wish to For their valuable comments, discussions, and feedback, we wish to
acknowledge Andy Bierman, Juergen Schoenwaelder, Rob Wilton, Joe acknowledge Andy Bierman, Juergen Schoenwaelder, Rob Wilton, Joe
Clarke, Kent Watsen Martin Bjorklund, Ladislav Lhotka, Qin Wu and Clarke, Kent Watsen Martin Bjorklund, Ladislav Lhotka, Qin Wu and
other members of the Netmod WG. other members of the Netmod WG.
9. References 8. References
9.1. Normative References 8.1. Normative References
[I-D.ietf-netmod-yang-data-ext] [I-D.ietf-netmod-yang-data-ext]
Bierman, A., Bjorklund, M., and K. Watsen, "YANG Data Bierman, A., Bjorklund, M., and K. Watsen, "YANG Data
Structure Extensions", draft-ietf-netmod-yang-data-ext-05 Structure Extensions", draft-ietf-netmod-yang-data-ext-05
(work in progress), December 2019. (work in progress), December 2019.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
DOI 10.17487/RFC3688, January 2004, Requirement Levels", BCP 14, RFC 2119,
<https://www.rfc-editor.org/info/rfc3688>. DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.
[RFC6243] Bierman, A. and B. Lengyel, "With-defaults Capability for [RFC6243] Bierman, A. and B. Lengyel, "With-defaults Capability for
NETCONF", RFC 6243, DOI 10.17487/RFC6243, June 2011, NETCONF", RFC 6243, DOI 10.17487/RFC6243, June 2011,
<https://www.rfc-editor.org/info/rfc6243>. <https://www.rfc-editor.org/info/rfc6243>.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016, RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/info/rfc7950>. <https://www.rfc-editor.org/info/rfc7950>.
[RFC7951] Lhotka, L., "JSON Encoding of Data Modeled with YANG", [RFC7951] Lhotka, L., "JSON Encoding of Data Modeled with YANG",
RFC 7951, DOI 10.17487/RFC7951, August 2016, RFC 7951, DOI 10.17487/RFC7951, August 2016,
<https://www.rfc-editor.org/info/rfc7951>. <https://www.rfc-editor.org/info/rfc7951>.
[RFC7952] Lhotka, L., "Defining and Using Metadata with YANG", [RFC7952] Lhotka, L., "Defining and Using Metadata with YANG",
RFC 7952, DOI 10.17487/RFC7952, August 2016, RFC 7952, DOI 10.17487/RFC7952, August 2016,
<https://www.rfc-editor.org/info/rfc7952>. <https://www.rfc-editor.org/info/rfc7952>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF [RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017, Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>. <https://www.rfc-editor.org/info/rfc8040>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
<https://www.rfc-editor.org/info/rfc8340>. <https://www.rfc-editor.org/info/rfc8340>.
[RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K., [RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "Network Management Datastore Architecture and R. Wilton, "Network Management Datastore Architecture
(NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018, (NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
<https://www.rfc-editor.org/info/rfc8342>. <https://www.rfc-editor.org/info/rfc8342>.
[RFC8525] Bierman, A., Bjorklund, M., Schoenwaelder, J., Watsen, K.,
and R. Wilton, "YANG Library", RFC 8525,
DOI 10.17487/RFC8525, March 2019,
<https://www.rfc-editor.org/info/rfc8525>.
[RFC8526] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K., [RFC8526] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "NETCONF Extensions to Support the Network and R. Wilton, "NETCONF Extensions to Support the Network
Management Datastore Architecture", RFC 8526, Management Datastore Architecture", RFC 8526,
DOI 10.17487/RFC8526, March 2019, DOI 10.17487/RFC8526, March 2019,
<https://www.rfc-editor.org/info/rfc8526>. <https://www.rfc-editor.org/info/rfc8526>.
[RFC8527] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K., [RFC8527] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "RESTCONF Extensions to Support the Network and R. Wilton, "RESTCONF Extensions to Support the Network
Management Datastore Architecture", RFC 8527, Management Datastore Architecture", RFC 8527,
DOI 10.17487/RFC8527, March 2019, DOI 10.17487/RFC8527, March 2019,
<https://www.rfc-editor.org/info/rfc8527>. <https://www.rfc-editor.org/info/rfc8527>.
9.2. Informative References 8.2. Informative References
[I-D.ietf-netmod-factory-default] [I-D.ietf-netmod-factory-default]
WU, Q., Lengyel, B., and Y. Niu, "Factory Default WU, Q., Lengyel, B., and Y. Niu, "A YANG Data Model for
Setting", draft-ietf-netmod-factory-default-10 (work in Factory Default Settings", draft-ietf-netmod-factory-
progress), February 2020. default-14 (work in progress), February 2020.
[I-D.verdt-netmod-yang-module-versioning] [I-D.verdt-netmod-yang-module-versioning]
Claise, B., Clarke, J., Rahman, R., Wilton, R., Lengyel, Claise, B., Clarke, J., Rahman, R., Wilton, R., Lengyel,
B., Sterne, J., and K. D'Souza, "Updated YANG Module B., Sterne, J., and K. D'Souza, "Updated YANG Module
Revision Handling", draft-verdt-netmod-yang-module- Revision Handling", draft-verdt-netmod-yang-module-
versioning-01 (work in progress), October 2019. versioning-01 (work in progress), October 2019.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC3688, January 2004,
DOI 10.17487/RFC2119, March 1997, <https://www.rfc-editor.org/info/rfc3688>.
<https://www.rfc-editor.org/info/rfc2119>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8525] Bierman, A., Bjorklund, M., Schoenwaelder, J., Watsen, K., [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
and R. Wilton, "YANG Library", RFC 8525, the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC8525, March 2019, DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc8525>. <https://www.rfc-editor.org/info/rfc6020>.
[RFC8632] Vallin, S. and M. Bjorklund, "A YANG Data Model for Alarm [RFC8632] Vallin, S. and M. Bjorklund, "A YANG Data Model for Alarm
Management", RFC 8632, DOI 10.17487/RFC8632, September Management", RFC 8632, DOI 10.17487/RFC8632, September
2019, <https://www.rfc-editor.org/info/rfc8632>. 2019, <https://www.rfc-editor.org/info/rfc8632>.
[RFC8641] Clemm, A. and E. Voit, "Subscription to YANG Notifications [RFC8641] Clemm, A. and E. Voit, "Subscription to YANG Notifications
for Datastore Updates", RFC 8641, DOI 10.17487/RFC8641, for Datastore Updates", RFC 8641, DOI 10.17487/RFC8641,
September 2019, <https://www.rfc-editor.org/info/rfc8641>. September 2019, <https://www.rfc-editor.org/info/rfc8641>.
Appendix A. Open Issues Appendix A. Open Issues
o - o -
Appendix B. Changes between revisions Appendix B. Changes between revisions
v07 - v08
o Moved compatibility into appendix
o Renamed yid-version to format-version as "yid" can be regarded as
a racial slur. Changed format to date of the YANG module
o Made support of ietf-yang-library mandatory if inline-content-
schema is supported
o Many small changes based on WGLC
v06 - v07 v06 - v07
o Updated terminology, use-cases o Updated terminology, use-cases
o Many small changes based on WGLC o Many small changes based on WGLC
v05 - v06 v05 - v06
o Modified module name format, removed .yin or .yang extension o Modified module name format, removed .yin or .yang extension
skipping to change at page 23, line 44 skipping to change at page 24, line 4
o Moved list of target modules into a separate <target-modules> o Moved list of target modules into a separate <target-modules>
element. element.
o Added backwards compatibility considerations o Added backwards compatibility considerations
v00 - v01 v00 - v01
o Added the target-ptr metadata with 3 methods o Added the target-ptr metadata with 3 methods
o Added timestamp metadata o Added timestamp metadata
o Removed usage of dedicated .yid file extension o Removed usage of dedicated .yid file extension
o Added list of use cases o Added list of use cases
o Added list of principles o Added list of principles
o Updated examples o Updated examples
o Moved detailed use case descriptions to appendix o Moved detailed use case descriptions to appendix
Appendix C. Detailed Use Cases - Non-Normative Appendix C. Backwards Compatibility
C.1. Use Cases The concept of backwards compatibility and what changes are backwards
compatible are not defined for instance data sets as it is highly
dependent on the specific use case and the content-schema.
For instance data that is the result of a design or specification
activity, some changes that may be good to avoid are listed. YANG
uses the concept of managed entities identified by key values; if the
connection between the represented entity and the key value is not
preserved during an update, this may lead to problems.
o If the key value of a list entry that represents the same managed
entity as before is changed, the user may mistakenly identify the
list entry as new.
o If the meaning of a list entry is changed, but the key values are
not (e.g., redefining an alarm-type but not changing its alarm-
type-id) the change may not be noticed.
o If the key value of a previously removed list entry is reused for
a different entity, the change may be misinterpreted as
reintroducing the previous entity.
Appendix D. Detailed Use Cases - Non-Normative
D.1. Use Cases
We present a number of use cases were YANG instance data is needed. We present a number of use cases were YANG instance data is needed.
C.1.1. Use Case 1: Early Documentation of Server Capabilities D.1.1. Use Case 1: Early Documentation of Server Capabilities
A server has a number of server-capabilities that are defined in YANG A server has a number of server-capabilities that are defined in YANG
modules and can be retrieved from the server using protocols like modules and can be retrieved from the server using protocols like
NETCONF or RESTCONF. Server capabilities include: NETCONF or RESTCONF. Server capabilities include:
o data defined in ietf-yang-library: YANG modules, submodules, o data defined in ietf-yang-library: YANG modules, submodules,
features, deviations, schema-mounts, and datastores supported features, deviations, schema-mounts, and datastores supported
([RFC8525]) ([RFC8525])
o alarms supported ([RFC8632]) o alarms supported ([RFC8632])
skipping to change at page 25, line 18 skipping to change at page 26, line 5
Most server-capabilities are relatively stable and change only during Most server-capabilities are relatively stable and change only during
upgrade or due to licensing or the addition or removal of hardware. upgrade or due to licensing or the addition or removal of hardware.
They are usually defined by a vendor at design time, before the They are usually defined by a vendor at design time, before the
product is released. It is feasible and advantageous to define/ product is released. It is feasible and advantageous to define/
document them early e.g., in a YANG instance data File. document them early e.g., in a YANG instance data File.
It is anticipated that a separate IETF document will define in detail It is anticipated that a separate IETF document will define in detail
how and which set of server capabilities should be documented. how and which set of server capabilities should be documented.
C.1.2. Use Case 2: Preloading Data D.1.2. Use Case 2: Preloading Data
There are parts of the configuration that must be fully configurable There are parts of the configuration that must be fully configurable
by the operator. However, often a simple default configuration will by the operator. However, often a simple default configuration will
be sufficient. be sufficient.
One example is access control groups/roles and related rules. While One example is access control groups/roles and related rules. While
a sophisticated operator may define dozens of different groups, often a sophisticated operator may define dozens of different groups, often
a basic (read-only operator, read-write system administrator, a basic (read-only operator, read-write system administrator,
security-administrator) triplet will be enough. Vendors will often security-administrator) triplet will be enough. Vendors will often
provide such default configuration data to make device configuration provide such default configuration data to make device configuration
easier for an operator. easier for an operator.
Defining access control data is a complex task. To help, the device Defining access control data is a complex task. To help, the device
vendor predefines a set of default groups (/nacm:nacm/groups) and vendor predefines a set of default groups (/nacm:nacm/groups) and
rules for these groups to access specific parts of common models rules for these groups to access specific parts of common models
(/nacm:nacm/rule-list/rule). (/nacm:nacm/rule-list/rule).
YANG instance data files are used to document and/or preload the YANG instance data files are used to document and/or preload the
default configuration. default configuration.
C.1.3. Use Case 3: Documenting Factory Default Settings D.1.3. Use Case 3: Documenting Factory Default Settings
Nearly every server has a factory default configuration. If the Nearly every server has a factory default configuration. If the
system is really badly misconfigured or if the current configuration system is really badly misconfigured or if the current configuration
is to be abandoned, the system can be reset the default factory is to be abandoned, the system can be reset the default factory
configuration. configuration.
In NETCONF, the <delete-config> operation can already be used to In NETCONF, the <delete-config> operation can already be used to
reset the startup datastore. There are ongoing efforts to introduce reset the startup datastore. There are ongoing efforts to introduce
a new, more generic factory-reset operation for the same purpose a new, more generic factory-reset operation for the same purpose
[I-D.ietf-netmod-factory-default] [I-D.ietf-netmod-factory-default]
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