NMDA Base Notification for Intent based configuration update

The YANG module in NETCONF Base Notifications [RFC6470] specifies the following 5 event notifications for the 'NETCONF' stream to notify a client application that the NETCONF server state has changed: netconf-config-change netconf-capability-change netconf-session-start netconf-session-end netconf-confirmed-commit These event notifications used within the 'NETCONF' stream are accessible to clients via the subscription mechanism described in [RFC5277]. This document introduces NMDA specific extension which allows a client to receive 1 notifications for additional common system events as follows: Generated when a server with network management protocol support interacts with hardware and detects that a set of configurations are not applied or none of them are not applied. Indicates the event and the current state of the applied configuration or data inconsistency issue between intended data initiated from the client and operational data saved in the server. NMDA datastore compare [I-D.ietf-netmod-nmda-diff] can be used to trigger consistency data check, i.e.,indicate the source of configuration node and check which part of configuration data is applied or which part of configuration data is not applied. A server MAY report events for non-NETCONF management sessions (such as RESTCONF,gPRC), using the 'session-id' value of zero. The following figure shows event notification sequence defined in this document.

+----------------------------+ |Server (device) | | | | | | +----------+ | | | Intended | | +------------+ | | datastore| | | | | +----------+ | |+----------+| | ^ | || Intended || | | | || config || | v | |+----------+| | +-------------+ | | |<----------------------> | | | | Client | <nmda-diff> rpc | NETCONF | | | (app) | | | engine | | | |<---------------------- | | | | | <intent-configuration +-------------+ | | | -update> notification / \ | +------------+ | / \ | | / \ | |+------------++---------+ | || Operational||system |+ | || datastore ||software ||+ | || ||component||| | |+------------++---------+|| | | +---------+| | | +---------+ | +----------------------------+ These notification messages are accessible to clients via either the subscription mechanism described in [RFC5277] or dynamic subscription mechanism and configured subscription mechanism described in [I-D.ietf-netconf-netconf-event-notifications].

The data model is defined in the ietf-nmda-notifications YANG module. Its structure is shown in the following figure. The notation syntax follows [RFC8340].

notifications: +---n intent-configuration-update +--ro app-tag? string +--ro src-ds? identityref +--ro dst-ds? identifyref +--ro (filter-spec)? | +--:(subtree-filter) | | +--ro subtree-filter? <anydata> | +--:(xpath-filter) | +--ro xpath-filter? yang:xpath1.0 {nc:xpath}? |--ro apply-result enumeration +--ro fail-applied-object* [edit-id] +--ro edit-id string +--ro operation enumeration +--ro object? ypatch:target-resource-offset +--ro value? <anydata> +--ro errors +--ro error* [] +--ro error-type enumeration +--ro error-tag string +--ro error-app-tag? string +--ro error-path? instance-identifier +--ro error-message? string +--ro error-info? <anydata> The following are examples of a apply-configuration-updated notification message:

<notification xmlns="urn:ietf:params:xml:ns:netconf:notification:1.0"> <eventTime>2017-06-16T16:30:59.137045+09:00</eventTime> <intent-configuration-update xmlns="urn:ietf:params:xml:ns:yang:ietf-nmda-notifications"> <app-tag>ds--module-a</app-tag> <datastore>intended</datastore> <datastore>operational</datastore> <fail-applied-object> <edit-id>1<edit-id> <operation>merge</operation> <target>/ietf-interfaces:interfaces-state</target> <value> <interfaces-state xmlns="http://foo.com/ietf-interfaces"> <interface> <name>eth0</name> <oper-status>down</oper-status> </interface> </interfaces-state> </value> </fail-applied-object> <fail-applied-object> <edit-id>2<edit-id> <target>/ietf-system:system</target> <errors> <error-type>protocol</error-type> <error-tag>mis-resource</error-tag> <error-path xmlns:ops="https://example.com/ns/ietf-system">\ \/if:interfaces-state\ \</error-path> <error-message>refer to resources that are not \ \available or otherwise not physically present.\ \</error-message> </errors> </fail-applied-object> </intent-configuration-update> </notification>

NMDA datastore compare [I-D.ietf-netmod-nmda-diff] could be used to check which part of configuration data is applied or which part of configuration data is not applied,e.g.,If a client creates an interface "et-0/0/0" but the interface does not physically exist at this point, the interface will appear in <intended> but does not does not exist in the <operational>. By comparing configuration difference between <intended> and <operational>, the interface that is not applied can be sorted out. Unlike [I-D.ietf-netmod-nmda-diff], the notification message only focuses on the configuration data that is not applied and the reason why the configuration changes were not applied. Also system internal interactions with hardware is needed within the server to make sure fail applied object is caused by mis-resource or remnant Configuration, etc.

This section presents the YANG module defined in this document. This module imports data types from the 'ietf-datastores' module defined in [RFC8342] and 'ietf-inet-types' module defined in [RFC6021].

<CODE BEGINS> file "ietf-nmda-notifications@2019-06-19.yang" module ietf-nmda-notifications { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-nmda-notifications"; prefix ndn; import ietf-datastores { prefix ds; } import ietf-inet-types { prefix inet; } import ietf-yang-types { prefix yang;} import ietf-yang-patch { prefix ypatch; } import ietf-netconf { prefix nc; } import ietf-restconf { prefix rc;} organization "IETF NETMOD (Network Modeling) Working Group"; contact "WG Web: <http://tools.ietf.org/wg/netmod/> WG List: <mailto:netmod@ietf.org> Editor: Qin Wu <mailto:bill.wu@huawei.com> Editor: Rohit R Ranade <mailto:rohitrranade@huawei.com>"; description "This module defines a YANG data model for use with the NETCONF and RESTCONF protocol that allows the client to receive additional common event notifications related to NMDA. Copyright (c) 2012 IETF Trust and the persons identified as the document authors. 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 (http://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 2019-06-19 { description "Initial version."; reference "RFC xxx: NETCONF Base Notifications for NMDA"; } typedef session-id-or-zero-type { type uint32; description "NETCONF Session Id or Zero to indicate none"; } feature error-info { description "This feature must also be enabled for that session if error-info can be advertised by the server. Otherwise, this feature must not be enabled."; } grouping common-session-parms { description "Common session parameters to identify a management session or internal interaction on a set of configuration data."; leaf username { type string; description "Name of the user for the session."; } leaf source-host { type inet:ip-address; description "Address of the remote host for the session."; } leaf session-id { type session-id-or-zero-type; description "Identifier of the session. A NETCONF session MUST be identified by a non-zero value. A non-NETCONF session MAY be identified by the value zero."; } leaf app-tag { type string; description "The application tag used to identify the managment session or internal interaction on a set of configuration data."; } } notification intent-configuration-updated { description "Generated when a server detects that a intended configuration applied event has occurred. Indicates the event and the current state of the intended data applying procedure in progress."; reference "RFC 8342, Section 5"; uses common-session-parms; leaf src-ds { type identityref { base ds:datastore; } description "Indicates which datastore is source of edit-data operation."; } leaf dst-ds { type identityref { base ds:datastore; } description "Indicates which datastore is target of edit-data operation."; } choice filter-spec { description "The content filter specification for this request."; anydata subtree-filter { description "This parameter identifies the portions of the target datastore to retrieve."; reference "RFC 6241: Network Configuration Protocol, Section 6."; } leaf xpath-filter { if-feature nc:xpath; type yang:xpath1.0; description "This parameter contains an XPath expression identifying the portions of the target datastore to retrieve. If the expression returns a node-set, all nodes in the node-set are selected by the filter. Otherwise, if the expression does not return a node-set, then the get-data operation fails. The expression is evaluated in the following XPath context: o The set of namespace declarations are those in scope on the 'xpath-filter' leaf element. o The set of variable bindings is empty. o The function library is the core function library, and the XPath functions defined in section 10 in RFC 7950. o The context node is the root node of the target datastore."; } } leaf apply-result { type enumeration { enum "partial-fail" { description "A set of configuration data is not applied."; } enum "fail" { description " None of configuration data is applied."; } enum "sucess" { description " All configuration data is applied."; } } description "Configuration data apply result."; } list fail-applied-object { when "../apply-result = 'partial-fail'"; key edit-id; ordered-by user; leaf edit-id { type string; description "Response status is for the 'edit' list entry with this 'edit-id' value."; } leaf operation { type enumeration { enum create { description "The target data node is created using the supplied value, only if it does not already exist. The 'target' leaf identifies the data node to be created, not the parent data node."; } enum delete { description "Delete the target node, only if the data resource currently exists; otherwise, return an error."; } enum insert { description "Insert the supplied value into a user-ordered list or leaf-list entry. The target node must represent a new data resource. If the 'where' parameter is set to 'before' or 'after', then the 'point' parameter identifies the insertion point for the target node."; } enum merge { description "The supplied value is merged with the target data node."; } enum move { description "Move the target node. Reorder a user-ordered list or leaf-list. The target node must represent an existing data resource. If the 'where' parameter is set to 'before' or 'after', then the 'point' parameter identifies the insertion point to move the target node."; } enum replace { description "The supplied value is used to replace the target data node."; } enum remove { description "Delete the target node if it currently exists."; } } mandatory true; description "The datastore operation requested for the associated 'edit' entry."; } leaf target { type ypatch:target-resource-offset; description "Topmost node associated with the configuration change. A server SHOULD set this object to the node within the datastore that is being altered. A server MAY set this object to one of the ancestors of the actual node that was changed, or omit this object, if the exact node is not known."; } anydata value { description "Value used for this edit operation. The anydata 'value' contains the target resource associated with the 'target' leaf. For example, suppose the target node is a YANG container named foo: container foo { leaf a { type string; } leaf b { type int32; } } The 'value' node contains one instance of foo: <value> <foo xmlns='example-foo-namespace'> <a>some value</a> <b>42</b> </foo> </value> "; } uses rc:errors {if-feature error-info;} description "List for fail applied objects that is not applied. "; } } } <CODE ENDS>