Internet-Draft | NETCONF Client and Server Models | December 2023 |
Watsen | Expires 30 June 2024 | [Page] |
This document defines two YANG modules, one module to configure a NETCONF client and the other module to configure a NETCONF server. Both modules support both the SSH and TLS transport protocols, and support both standard NETCONF and NETCONF Call Home connections.¶
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BBBB
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CCCC
--> the assigned RFC value for draft-ietf-netconf-keystore¶
DDDD
--> the assigned RFC value for draft-ietf-netconf-tcp-client-server¶
EEEE
--> the assigned RFC value for draft-ietf-netconf-ssh-client-server¶
FFFF
--> the assigned RFC value for draft-ietf-netconf-tls-client-server¶
GGGG
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This document defines two YANG [RFC7950] modules, one module to configure a NETCONF [RFC6241] client and the other module to configure a NETCONF server. Both modules support both NETCONF over SSH [RFC6242] and NETCONF over TLS [RFC7589] and NETCONF Call Home connections [RFC8071].¶
This document presents one or more YANG modules [RFC7950] that are part of a collection of RFCs that work together to, ultimately, enable the configuration of both the clients and servers of both the NETCONF [RFC6241] and RESTCONF [RFC8040] protocols.¶
The dependency relationship between the primary YANG groupings defined in the various RFCs is presented in the below diagram. In some cases, a draft may define secondary groupings that introduce dependencies not illustrated in the diagram. The labels in the diagram are a shorthand name for the defining RFC. The citation reference for shorthand name is provided below the diagram.¶
crypto-types ^ ^ / \ / \ truststore keystore ^ ^ ^ ^ | +---------+ | | | | | | | +------------+ | tcp-client-server | / | | ^ ^ ssh-client-server | | | | ^ tls-client-server | | | ^ ^ http-client-server | | | | | ^ | | | +-----+ +---------+ | | | | | | | | +-----------|--------|--------------+ | | | | | | | | +-----------+ | | | | | | | | | | | | | | | | | netconf-client-server restconf-client-server¶
Label in Diagram | Originating RFC |
---|---|
crypto-types | [I-D.ietf-netconf-crypto-types] |
truststore | [I-D.ietf-netconf-trust-anchors] |
keystore | [I-D.ietf-netconf-keystore] |
tcp-client-server | [I-D.ietf-netconf-tcp-client-server] |
ssh-client-server | [I-D.ietf-netconf-ssh-client-server] |
tls-client-server | [I-D.ietf-netconf-tls-client-server] |
http-client-server | [I-D.ietf-netconf-http-client-server] |
netconf-client-server | [I-D.ietf-netconf-netconf-client-server] |
restconf-client-server | [I-D.ietf-netconf-restconf-client-server] |
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.¶
This document is compliant with the Network Management Datastore Architecture (NMDA) [RFC8342]. For instance, as described in [I-D.ietf-netconf-trust-anchors] and [I-D.ietf-netconf-keystore], trust anchors and keys installed during manufacturing are expected to appear in <operational>.¶
Various examples used in this document use a placeholder value for binary data that has been base64 encoded (e.g., "BASE64VALUE="). This placeholder value is used as real base64 encoded structures are often many lines long and hence distracting to the example being presented.¶
The NETCONF client model presented in this section supports both clients initiating connections to servers, as well as clients listening for connections from servers calling home, using either the SSH and TLS transport protocols.¶
YANG feature statements are used to enable implementations to advertise which potentially uncommon parts of the model the NETCONF client supports.¶
This section provides an overview of the "ietf-netconf-client" module in terms of its features and groupings.¶
The following diagram lists all the "feature" statements defined in the "ietf-netconf-client" module:¶
Features: +-- ssh-initiate +-- tls-initiate +-- ssh-listen +-- tls-listen +-- central-netconf-client-supported¶
The diagram above uses syntax that is similar to but not defined in [RFC8340].¶
The "ietf-netconf-client" module defines the following "grouping" statements:¶
Each of these groupings are presented in the following subsections.¶
The following tree diagram [RFC8340] illustrates the "netconf-client-initiate-stack-grouping" grouping:¶
grouping netconf-client-initiate-stack-grouping: +-- (transport) +--:(ssh) {ssh-initiate}? | +-- ssh | +-- tcp-client-parameters | | +---u tcpc:tcp-client-grouping | +-- ssh-client-parameters | | +---u sshc:ssh-client-grouping | +-- netconf-client-parameters | +--u ncc:netconf-client-grouping +--:(tls) {tls-initiate}? +-- tls +-- tcp-client-parameters | +---u tcpc:tcp-client-grouping +-- tls-client-parameters | +---u tlsc:tls-client-grouping +-- netconf-client-parameters +---u ncc:netconf-client-grouping¶
Comments:¶
For the referenced grouping statement(s):¶
The following tree diagram [RFC8340] illustrates the "netconf-client-listen-stack-grouping" grouping:¶
grouping netconf-client-listen-stack-grouping: +-- (transport) +--:(ssh) {ssh-listen}? | +-- ssh | +-- tcp-server-parameters | | +---u tcps:tcp-server-grouping | +-- ssh-client-parameters | | +---u sshc:ssh-client-grouping | +-- netconf-client-parameters | +--u ncc:netconf-client-grouping +--:(tls) {tls-listen}? +-- tls +-- tcp-server-parameters | +---u tcps:tcp-server-grouping +-- tls-client-parameters | +---u tlsc:tls-client-grouping +-- netconf-client-parameters +---u ncc:netconf-client-grouping¶
Comments:¶
For the referenced grouping statement(s):¶
The following tree diagram [RFC8340] illustrates the "netconf-client-app-grouping" grouping:¶
grouping netconf-client-app-grouping: +-- initiate! {ssh-initiate or tls-initiate}? | +-- netconf-server* [name] | +-- name? string | +-- endpoints | | +-- endpoint* [name] | | +-- name? string | | +---u netconf-client-initiate-stack-grouping | +-- connection-type | | +-- (connection-type) | | +--:(persistent-connection) | | | +-- persistent! | | +--:(periodic-connection) | | +-- periodic! | | +-- period? uint16 | | +-- anchor-time? yang:date-and-time | | +-- idle-timeout? uint16 | +-- reconnect-strategy | +-- start-with? enumeration | +-- max-wait? uint16 | +-- max-attempts? uint8 +-- listen! {ssh-listen or tls-listen}? +-- idle-timeout? uint16 +-- endpoints +-- endpoint* [name] +-- name? string +---u netconf-client-listen-stack-grouping¶
Comments:¶
For the referenced grouping statement(s):¶
The following tree diagram [RFC8340] lists all the protocol-accessible nodes defined in the "ietf-netconf-client" module:¶
module: ietf-netconf-client +--rw netconf-client {central-netconf-client-supported}? +---u netconf-client-app-grouping¶
Comments:¶
The following example illustrates configuring a NETCONF client to initiate connections, using both the SSH and TLS transport protocols, as well as to listen for call-home connections, again using both the SSH and TLS transport protocols.¶
This example is consistent with the examples presented in Section 2.2 of [I-D.ietf-netconf-trust-anchors] and Section 2.2 of [I-D.ietf-netconf-keystore].¶
=============== NOTE: '\' line wrapping per RFC 8792 ================ <netconf-client xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-clie\ nt"> <!-- NETCONF servers to initiate connections to --> <initiate> <netconf-server> <name>corp-fw1</name> <endpoints> <endpoint> <name>corp-fw1.example.com</name> <ssh> <tcp-client-parameters> <remote-address>corp-fw1.example.com</remote-address> <keepalives> <idle-time>7200</idle-time> <max-probes>9</max-probes> <probe-interval>75</probe-interval> </keepalives> </tcp-client-parameters> <ssh-client-parameters> <client-identity> <username>foobar</username> <public-key> <central-keystore-reference>ssh-rsa-key</central-k\ eystore-reference> </public-key> </client-identity> <server-authentication> <ca-certs> <central-truststore-reference>trusted-server-ca-ce\ rts</central-truststore-reference> </ca-certs> <ee-certs> <central-truststore-reference>trusted-server-ee-ce\ rts</central-truststore-reference> </ee-certs> </server-authentication> <keepalives> <max-wait>30</max-wait> <max-attempts>3</max-attempts> </keepalives> </ssh-client-parameters> </ssh> </endpoint> <endpoint> <name>corp-fw2.example.com</name> <tls> <tcp-client-parameters> <remote-address>corp-fw2.example.com</remote-address> <keepalives> <idle-time>7200</idle-time> <max-probes>9</max-probes> <probe-interval>75</probe-interval> </keepalives> </tcp-client-parameters> <tls-client-parameters> <client-identity> <certificate> <central-keystore-reference> <asymmetric-key>rsa-asymmetric-key</asymmetric-k\ ey> <certificate>ex-rsa-cert</certificate> </central-keystore-reference> </certificate> </client-identity> <server-authentication> <ca-certs> <central-truststore-reference>trusted-server-ca-ce\ rts</central-truststore-reference> </ca-certs> <ee-certs> <central-truststore-reference>trusted-server-ee-ce\ rts</central-truststore-reference> </ee-certs> </server-authentication> <keepalives> <test-peer-aliveness> <max-wait>30</max-wait> <max-attempts>3</max-attempts> </test-peer-aliveness> </keepalives> </tls-client-parameters> </tls> </endpoint> </endpoints> <connection-type> <persistent/> </connection-type> <reconnect-strategy> <start-with>last-connected</start-with> </reconnect-strategy> </netconf-server> </initiate> <!-- endpoints to listen for NETCONF Call Home connections on --> <listen> <endpoints> <endpoint> <name>Intranet-facing SSH listener</name> <ssh> <tcp-server-parameters> <local-address>192.0.2.7</local-address> </tcp-server-parameters> <ssh-client-parameters> <client-identity> <username>foobar</username> <public-key> <central-keystore-reference>ssh-rsa-key</central-key\ store-reference> </public-key> </client-identity> <server-authentication> <ca-certs> <central-truststore-reference>trusted-server-ca-cert\ s</central-truststore-reference> </ca-certs> <ee-certs> <central-truststore-reference>trusted-server-ee-cert\ s</central-truststore-reference> </ee-certs> <ssh-host-keys> <central-truststore-reference>trusted-ssh-public-key\ s</central-truststore-reference> </ssh-host-keys> </server-authentication> </ssh-client-parameters> </ssh> </endpoint> <endpoint> <name>Intranet-facing TLS listener</name> <tls> <tcp-server-parameters> <local-address>192.0.2.7</local-address> </tcp-server-parameters> <tls-client-parameters> <client-identity> <certificate> <central-keystore-reference> <asymmetric-key>rsa-asymmetric-key</asymmetric-key> <certificate>ex-rsa-cert</certificate> </central-keystore-reference> </certificate> </client-identity> <server-authentication> <ca-certs> <central-truststore-reference>trusted-server-ca-cert\ s</central-truststore-reference> </ca-certs> <ee-certs> <central-truststore-reference>trusted-server-ee-cert\ s</central-truststore-reference> </ee-certs> </server-authentication> <keepalives> <peer-allowed-to-send/> </keepalives> </tls-client-parameters> </tls> </endpoint> </endpoints> </listen> </netconf-client>¶
This YANG module has normative references to [RFC6242], [RFC6991], [RFC7589], [RFC8071], [I-D.ietf-netconf-tcp-client-server], [I-D.ietf-netconf-ssh-client-server], and [I-D.ietf-netconf-tls-client-server].¶
<CODE BEGINS> file "ietf-netconf-client@2023-12-28.yang"¶
module ietf-netconf-client { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-netconf-client"; prefix ncc; import ietf-yang-types { prefix yang; reference "RFC 6991: Common YANG Data Types"; } import ietf-tcp-client { prefix tcpc; reference "RFC DDDD: YANG Groupings for TCP Clients and TCP Servers"; } import ietf-tcp-server { prefix tcps; reference "RFC DDDD: YANG Groupings for TCP Clients and TCP Servers"; } import ietf-ssh-client { prefix sshc; reference "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers"; } import ietf-tls-client { prefix tlsc; reference "RFC FFFF: YANG Groupings for TLS Clients and TLS Servers"; } organization "IETF NETCONF (Network Configuration) Working Group"; contact "WG Web: https://datatracker.ietf.org/wg/netconf WG List: NETCONF WG list <mailto:netconf@ietf.org> Author: Kent Watsen <mailto:kent+ietf@watsen.net>"; description "This module contains a collection of YANG definitions for configuring NETCONF clients. 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 HHHH (https://www.rfc-editor.org/info/rfcHHHH); see the RFC itself for full legal notices. The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document are to be interpreted as described in BCP 14 (RFC 2119) (RFC 8174) when, and only when, they appear in all capitals, as shown here."; revision 2023-12-28 { description "Initial version"; reference "RFC HHHH: NETCONF Client and Server Models"; } // Features feature ssh-initiate { description "The 'ssh-initiate' feature indicates that the NETCONF client supports initiating SSH connections to NETCONF servers."; reference "RFC 6242: Using the NETCONF Protocol over Secure Shell (SSH)"; } feature tls-initiate { description "The 'tls-initiate' feature indicates that the NETCONF client supports initiating TLS connections to NETCONF servers."; reference "RFC 7589: Using the NETCONF Protocol over Transport Layer Security (TLS) with Mutual X.509 Authentication"; } feature ssh-listen { description "The 'ssh-listen' feature indicates that the NETCONF client supports opening a port to listen for incoming NETCONF server call-home SSH connections."; reference "RFC 8071: NETCONF Call Home and RESTCONF Call Home"; } feature tls-listen { description "The 'tls-listen' feature indicates that the NETCONF client supports opening a port to listen for incoming NETCONF server call-home TLS connections."; reference "RFC 8071: NETCONF Call Home and RESTCONF Call Home"; } feature central-netconf-client-supported { description "The 'central-netconf-client-supported' feature indicates that the server that implements this module supports the top-level 'netconf-client' node. This feature is needed as some servers may want to use features defined in this module, which requires this module to be implemented, without having to support the top-level 'netconf-client' node."; } // Groupings grouping netconf-client-grouping { description "A reusable grouping for configuring a NETCONF client without any consideration for how underlying transport sessions are established. This grouping currently does not define any nodes. It exists only so the model can be consistent with other 'client-server' models."; } grouping netconf-client-initiate-stack-grouping { description "A reusable grouping for configuring a NETCONF client 'initiate' protocol stack for a single outbound connection."; choice transport { mandatory true; description "Selects between available transports."; case ssh { if-feature "ssh-initiate"; container ssh { description "Specifies TCP, SSH, and NETCONF configuration for the connection."; container tcp-client-parameters { description "TCP-level client parameters to initiate a NETCONF over SSH connection."; uses tcpc:tcp-client-grouping { refine "remote-port" { default "830"; description "The NETCONF client will attempt to connect to the IANA-assigned well-known port value for 'netconf-ssh' (830) if no value is specified."; } } } container ssh-client-parameters { description "SSH-level client parameters to initiate a NETCONF over SSH connection."; uses sshc:ssh-client-grouping; } container netconf-client-parameters { description "NETCONF-level client parameters to initiate a NETCONF over SSH connection."; uses ncc:netconf-client-grouping; } } } case tls { if-feature "tls-initiate"; container tls { description "Specifies TCP, TLS, and NETCONF configuration for the connection."; container tcp-client-parameters { description "TCP-level client parameters to initiate a NETCONF over TLS connection."; uses tcpc:tcp-client-grouping { refine "remote-port" { default "6513"; description "The NETCONF client will attempt to connect to the IANA-assigned well-known port value for 'netconf-tls' (6513) if no value is specified."; } } } container tls-client-parameters { must client-identity { description "NETCONF/TLS clients MUST pass some authentication credentials."; } description "TLS-level client parameters to initiate a NETCONF over TLS connection."; uses tlsc:tls-client-grouping; } container netconf-client-parameters { description "NETCONF-level client parameters to initiate a NETCONF over TLS connection."; uses ncc:netconf-client-grouping; } } } } } // netconf-client-initiate-stack-grouping grouping netconf-client-listen-stack-grouping { description "A reusable grouping for configuring a NETCONF client 'listen' protocol stack for listening on a single port. The 'listen' stack supports call home connections, as described in RFC 8071"; reference "RFC 8071: NETCONF Call Home and RESTCONF Call Home"; choice transport { mandatory true; description "Selects between available transports."; case ssh { if-feature "ssh-listen"; container ssh { description "TCP, SSH, and NETCONF configuration to listen for NETCONF over SSH Call Home connections."; container tcp-server-parameters { description "TCP-level server parameters to listen for NETCONF over SSH Call Home connections."; uses tcps:tcp-server-grouping { refine "local-port" { default "4334"; description "The NETCONF client will listen on the IANA- assigned well-known port for 'netconf-ch-ssh' (4334) if no value is specified."; } } } container ssh-client-parameters { description "SSH-level client parameters to listen for NETCONF over SSH Call Home connections."; uses sshc:ssh-client-grouping; } container netconf-client-parameters { description "NETCONF-level client parameters to listen for NETCONF over SSH Call Home connections."; uses ncc:netconf-client-grouping; } } } case tls { if-feature "tls-listen"; container tls { description "TCP, TLS, and NETCONF configuration to listen for NETCONF over TLS Call Home connections."; container tcp-server-parameters { description "TCP-level server parameters to listen for NETCONF over TLS Call Home connections."; uses tcps:tcp-server-grouping { refine "local-port" { default "4335"; description "The NETCONF client will listen on the IANA- assigned well-known port for 'netconf-ch-tls' (4335) if no value is specified."; } } } container tls-client-parameters { must client-identity { description "NETCONF/TLS clients MUST pass some authentication credentials."; } description "TLS-level client parameters to listen for NETCONF over TLS Call Home connections."; uses tlsc:tls-client-grouping; } container netconf-client-parameters { description "NETCONF-level client parameters to listen for NETCONF over TLS Call Home connections."; uses ncc:netconf-client-grouping; } } } } } // netconf-client-listen-stack-grouping grouping netconf-client-app-grouping { description "A reusable grouping for configuring a NETCONF client application that supports both 'initiate' and 'listen' protocol stacks for a multiplicity of connections."; container initiate { if-feature "ssh-initiate or tls-initiate"; presence "Indicates that client-initiated connections have been configured. This statement is present so the mandatory descendant nodes do not imply that this node must be configured."; description "Configures client initiating underlying TCP connections."; list netconf-server { key "name"; min-elements 1; description "List of NETCONF servers the NETCONF client is to maintain simultaneous connections with."; leaf name { type string; description "An arbitrary name for the NETCONF server."; } container endpoints { description "Container for the list of endpoints."; list endpoint { key "name"; min-elements 1; ordered-by user; description "A user-ordered list of endpoints that the NETCONF client will attempt to connect to in the specified sequence. Defining more than one enables high-availability."; leaf name { type string; description "An arbitrary name for the endpoint."; } uses netconf-client-initiate-stack-grouping; } // list endpoint } // container endpoints container connection-type { description "Indicates the NETCONF client's preference for how the NETCONF connection is maintained."; choice connection-type { mandatory true; description "Selects between available connection types."; case persistent-connection { container persistent { presence "Indicates that a persistent connection is to be maintained."; description "Maintain a persistent connection to the NETCONF server. If the connection goes down, immediately start trying to reconnect to the NETCONF server, using the reconnection strategy. This connection type minimizes any NETCONF server to NETCONF client data-transfer delay, albeit at the expense of holding resources longer."; } } case periodic-connection { container periodic { presence "Indicates that a periodic connection is to be maintained."; description "Periodically connect to the NETCONF server. This connection type decreases resource utilization, albeit with increased delay in NETCONF server to NETCONF client interactions. The NETCONF client should close the underlying TCP connection upon completing planned activities. Connections are established at the same start time regardless how long the previous connection stayed open. In the case that the previous connection is still active, establishing a new connection is NOT RECOMMENDED."; leaf period { type uint16; units "minutes"; default "60"; description "Duration of time between periodic connections."; } leaf anchor-time { type yang:date-and-time { // constrained to minute-level granularity pattern '[0-9]{4}-(1[0-2]|0[1-9])-(0[1-9]|[1-2]' + '[0-9]|3[0-1])T(0[0-9]|1[0-9]|2[0-3]):[' + '0-5][0-9]:00(Z|[\+\-]((1[0-3]|0[0-9]):' + '([0-5][0-9])|14:00))?'; } description "Designates a timestamp before or after which a series of periodic connections are determined. The periodic connections occur at a whole multiple interval from the anchor time. If an 'anchor-time' is not provided, then the server may implicitly set it to the time when this configuraton is applied (e.g., on boot). For example, for an anchor time is 15 minutes past midnight and a period interval of 24 hours, then a periodic connection will occur 15 minutes past midnight everyday."; } leaf idle-timeout { type uint16; units "seconds"; default 180; // three minutes description "Specifies the maximum number of seconds that a NETCONF session may remain idle. A NETCONF session will be dropped if it is idle for an interval longer then this number of seconds. If set to zero, then the NETCONF client will never drop a session because it is idle."; } } } } } container reconnect-strategy { description "The reconnection strategy directs how a NETCONF client reconnects to a NETCONF server, after discovering its connection to the server has dropped, even if due to a reboot. The NETCONF client starts with the specified endpoint and tries to connect to it max-attempts times before trying the next endpoint in the list (round robin)."; leaf start-with { type enumeration { enum first-listed { description "Indicates that reconnections should start with the first endpoint listed."; } enum last-connected { description "Indicates that reconnections should start with the endpoint last connected to. If no previous connection has ever been established, then the first endpoint configured is used. NETCONF clients SHOULD be able to remember the last endpoint connected to across reboots."; } enum random-selection { description "Indicates that reconnections should start with a random endpoint."; } } default "first-listed"; description "Specifies which of the NETCONF server's endpoints the NETCONF client should start with when trying to connect to the NETCONF server."; } leaf max-wait { type uint16 { range "1..max"; } units "seconds"; default "5"; description "Specifies the amount of time in seconds after which, if the connection is not established, an endpoint connection attempt is considered unsuccessful."; } leaf max-attempts { type uint8 { range "1..max"; } default "3"; description "Specifies the number times the NETCONF client tries to connect to a specific endpoint before moving on to the next endpoint in the list (round robin)."; } } } // netconf-server } // initiate container listen { if-feature "ssh-listen or tls-listen"; presence "Indicates that client-listening ports have been configured. This statement is present so the mandatory descendant nodes do not imply that this node must be configured."; description "Configures the client to accept call-home TCP connections."; leaf idle-timeout { type uint16; units "seconds"; default "180"; // three minutes description "Specifies the maximum number of seconds that a NETCONF session may remain idle. A NETCONF session will be dropped if it is idle for an interval longer than this number of seconds. If set to zero, then the server will never drop a session because it is idle."; } container endpoints { description "Container for a list of endpoints."; list endpoint { key "name"; min-elements 1; description "List of endpoints to listen for NETCONF connections."; leaf name { type string; description "An arbitrary name for the NETCONF listen endpoint."; } uses netconf-client-listen-stack-grouping; } } } // listen } // netconf-client-app-grouping // Protocol accessible node for clients that implement this module. container netconf-client { if-feature central-netconf-client-supported; uses netconf-client-app-grouping; description "Top-level container for NETCONF client configuration."; } }¶
<CODE ENDS>¶
The NETCONF server model presented in this section supports both listening for connections as well as initiating call-home connections, using either the SSH and TLS transport protocols.¶
YANG feature statements are used to enable implementations to advertise which potentially uncommon parts of the model the NETCONF server supports.¶
This section provides an overview of the "ietf-netconf-server" module in terms of its features and groupings.¶
The following diagram lists all the "feature" statements defined in the "ietf-netconf-server" module:¶
Features: +-- ssh-listen +-- tls-listen +-- ssh-call-home +-- tls-call-home +-- central-netconf-server-supported¶
The diagram above uses syntax that is similar to but not defined in [RFC8340].¶
The "ietf-netconf-server" module defines the following "grouping" statements:¶
Each of these groupings are presented in the following subsections.¶
The following tree diagram [RFC8340] illustrates the "netconf-server-grouping" grouping:¶
grouping netconf-server-grouping: +-- client-identity-mappings +---u x509c2n:cert-to-name¶
Comments:¶
For the referenced grouping statement(s):¶
The following tree diagram [RFC8340] illustrates the "netconf-server-listen-stack-grouping" grouping:¶
grouping netconf-server-listen-stack-grouping: +-- (transport) +--:(ssh) {ssh-listen}? | +-- ssh | +-- tcp-server-parameters | | +---u tcps:tcp-server-grouping | +-- ssh-server-parameters | | +---u sshs:ssh-server-grouping | +-- netconf-server-parameters | +---u ncs:netconf-server-grouping +--:(tls) {tls-listen}? +-- tls +-- tcp-server-parameters | +---u tcps:tcp-server-grouping +-- tls-server-parameters | +---u tlss:tls-server-grouping +-- netconf-server-parameters +---u ncs:netconf-server-grouping¶
Comments:¶
For the referenced grouping statement(s):¶
The following tree diagram [RFC8340] illustrates the "netconf-server-callhome-stack-grouping" grouping:¶
grouping netconf-server-callhome-stack-grouping: +-- (transport) +--:(ssh) {ssh-call-home}? | +-- ssh | +-- tcp-client-parameters | | +---u tcpc:tcp-client-grouping | +-- ssh-server-parameters | | +---u sshs:ssh-server-grouping | +-- netconf-server-parameters | +---u ncs:netconf-server-grouping +--:(tls) {tls-call-home}? +-- tls +-- tcp-client-parameters | +---u tcpc:tcp-client-grouping +-- tls-server-parameters | +---u tlss:tls-server-grouping +-- netconf-server-parameters +---u ncs:netconf-server-grouping¶
Comments:¶
For the referenced grouping statement(s):¶
The following tree diagram [RFC8340] illustrates the "netconf-server-app-grouping" grouping:¶
grouping netconf-server-app-grouping: +-- listen! {ssh-listen or tls-listen}? | +-- idle-timeout? uint16 | +-- endpoints | +-- endpoint* [name] | +-- name? string | +---u netconf-server-listen-stack-grouping +-- call-home! {ssh-call-home or tls-call-home}? +-- netconf-client* [name] +-- name? string +-- endpoints | +-- endpoint* [name] | +-- name? string | +---u netconf-server-callhome-stack-grouping +-- connection-type | +-- (connection-type) | +--:(persistent-connection) | | +-- persistent! | +--:(periodic-connection) | +-- periodic! | +-- period? uint16 | +-- anchor-time? yang:date-and-time | +-- idle-timeout? uint16 +-- reconnect-strategy +-- start-with? enumeration +-- max-wait? uint16 +-- max-attempts? uint8¶
Comments:¶
For the referenced grouping statement(s):¶
The following tree diagram [RFC8340] lists all the protocol-accessible nodes defined in the "ietf-netconf-server" module:¶
module: ietf-netconf-server +--rw netconf-server {central-netconf-server-supported}? +---u netconf-server-app-grouping¶
Comments:¶
The following example illustrates configuring a NETCONF server to listen for NETCONF client connections using both the SSH and TLS transport protocols, as well as configuring call-home to two NETCONF clients, one using SSH and the other using TLS.¶
This example is consistent with the examples presented in Section 2.2 of [I-D.ietf-netconf-trust-anchors] and Section 2.2 of [I-D.ietf-netconf-keystore].¶
=============== NOTE: '\' line wrapping per RFC 8792 ================ <netconf-server xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-server" xmlns:x509c2n="urn:ietf:params:xml:ns:yang:ietf-x509-cert-to-name"> <!-- endpoints to listen for NETCONF connections on --> <listen> <endpoints> <endpoint> <!-- listening for SSH connections --> <name>netconf/ssh</name> <ssh> <tcp-server-parameters> <local-address>192.0.2.7</local-address> </tcp-server-parameters> <ssh-server-parameters> <server-identity> <host-key> <name>deployment-specific-certificate</name> <public-key> <central-keystore-reference>ssh-rsa-key</central-k\ eystore-reference> </public-key> </host-key> </server-identity> <client-authentication> </client-authentication> </ssh-server-parameters> <netconf-server-parameters> <!-- nothing to configure --> </netconf-server-parameters> </ssh> </endpoint> <endpoint> <!-- listening for TLS sessions --> <name>netconf/tls</name> <tls> <tcp-server-parameters> <local-address>192.0.2.7</local-address> </tcp-server-parameters> <tls-server-parameters> <server-identity> <certificate> <central-keystore-reference> <asymmetric-key>rsa-asymmetric-key</asymmetric-key> <certificate>ex-rsa-cert</certificate> </central-keystore-reference> </certificate> </server-identity> <client-authentication> <ca-certs> <central-truststore-reference>trusted-client-ca-cert\ s</central-truststore-reference> </ca-certs> <ee-certs> <central-truststore-reference>trusted-client-ee-cert\ s</central-truststore-reference> </ee-certs> </client-authentication> <keepalives> <peer-allowed-to-send/> </keepalives> </tls-server-parameters> <netconf-server-parameters> <client-identity-mappings> <cert-to-name> <id>1</id> <fingerprint>11:0A:05:11:00</fingerprint> <map-type>x509c2n:specified</map-type> <name>scooby-doo</name> </cert-to-name> <cert-to-name> <id>2</id> <map-type>x509c2n:san-any</map-type> </cert-to-name> </client-identity-mappings> </netconf-server-parameters> </tls> </endpoint> </endpoints> </listen> <!-- calling home to SSH and TLS based NETCONF clients --> <call-home> <netconf-client> <!-- SSH-based client --> <name>config-mgr</name> <endpoints> <endpoint> <name>east-data-center</name> <ssh> <tcp-client-parameters> <remote-address>east.config-mgr.example.com</remote-ad\ dress> <keepalives> <idle-time>7200</idle-time> <max-probes>9</max-probes> <probe-interval>75</probe-interval> </keepalives> </tcp-client-parameters> <ssh-server-parameters> <server-identity> <host-key> <name>deployment-specific-certificate</name> <public-key> <central-keystore-reference>ssh-rsa-key</central\ -keystore-reference> </public-key> </host-key> </server-identity> </ssh-server-parameters> <netconf-server-parameters> <!-- nothing to configure --> </netconf-server-parameters> </ssh> </endpoint> <endpoint> <name>west-data-center</name> <ssh> <tcp-client-parameters> <remote-address>west.config-mgr.example.com</remote-ad\ dress> </tcp-client-parameters> <ssh-server-parameters> <server-identity> <host-key> <name>deployment-specific-certificate</name> <public-key> <central-keystore-reference>ssh-rsa-key</central\ -keystore-reference> </public-key> </host-key> </server-identity> </ssh-server-parameters> <netconf-server-parameters> <!-- nothing to configure --> </netconf-server-parameters> </ssh> </endpoint> </endpoints> <connection-type> <periodic> <idle-timeout>300</idle-timeout> <period>60</period> </periodic> </connection-type> <reconnect-strategy> <start-with>last-connected</start-with> <max-wait>3</max-wait> <max-attempts>3</max-attempts> </reconnect-strategy> </netconf-client> <netconf-client> <!-- TLS-based client --> <name>data-collector</name> <endpoints> <endpoint> <name>east-data-center</name> <tls> <tcp-client-parameters> <remote-address>east.analytics.example.com</remote-add\ ress> <keepalives> <idle-time>7200</idle-time> <max-probes>9</max-probes> <probe-interval>75</probe-interval> </keepalives> </tcp-client-parameters> <tls-server-parameters> <server-identity> <certificate> <central-keystore-reference> <asymmetric-key>rsa-asymmetric-key</asymmetric-k\ ey> <certificate>ex-rsa-cert</certificate> </central-keystore-reference> </certificate> </server-identity> <client-authentication> <ca-certs> <central-truststore-reference>trusted-client-ca-ce\ rts</central-truststore-reference> </ca-certs> <ee-certs> <central-truststore-reference>trusted-client-ee-ce\ rts</central-truststore-reference> </ee-certs> </client-authentication> <keepalives> <test-peer-aliveness> <max-wait>30</max-wait> <max-attempts>3</max-attempts> </test-peer-aliveness> </keepalives> </tls-server-parameters> <netconf-server-parameters> <client-identity-mappings> <cert-to-name> <id>1</id> <fingerprint>11:0A:05:11:00</fingerprint> <map-type>x509c2n:specified</map-type> <name>scooby-doo</name> </cert-to-name> <cert-to-name> <id>2</id> <map-type>x509c2n:san-any</map-type> </cert-to-name> </client-identity-mappings> </netconf-server-parameters> </tls> </endpoint> <endpoint> <name>west-data-center</name> <tls> <tcp-client-parameters> <remote-address>west.analytics.example.com</remote-add\ ress> <keepalives> <idle-time>7200</idle-time> <max-probes>9</max-probes> <probe-interval>75</probe-interval> </keepalives> </tcp-client-parameters> <tls-server-parameters> <server-identity> <certificate> <central-keystore-reference> <asymmetric-key>rsa-asymmetric-key</asymmetric-k\ ey> <certificate>ex-rsa-cert</certificate> </central-keystore-reference> </certificate> </server-identity> <client-authentication> <ca-certs> <central-truststore-reference>trusted-client-ca-ce\ rts</central-truststore-reference> </ca-certs> <ee-certs> <central-truststore-reference>trusted-client-ee-ce\ rts</central-truststore-reference> </ee-certs> </client-authentication> <keepalives> <test-peer-aliveness> <max-wait>30</max-wait> <max-attempts>3</max-attempts> </test-peer-aliveness> </keepalives> </tls-server-parameters> <netconf-server-parameters> <client-identity-mappings> <cert-to-name> <id>1</id> <fingerprint>11:0A:05:11:00</fingerprint> <map-type>x509c2n:specified</map-type> <name>scooby-doo</name> </cert-to-name> <cert-to-name> <id>2</id> <map-type>x509c2n:san-any</map-type> </cert-to-name> </client-identity-mappings> </netconf-server-parameters> </tls> </endpoint> </endpoints> <connection-type> <persistent/> </connection-type> <reconnect-strategy> <start-with>first-listed</start-with> <max-wait>3</max-wait> <max-attempts>3</max-attempts> </reconnect-strategy> </netconf-client> </call-home> </netconf-server>¶
This YANG module has normative references to [RFC6242], [RFC6991], [RFC7407], [RFC7589], [RFC8071], [I-D.ietf-netconf-tcp-client-server], [I-D.ietf-netconf-ssh-client-server], and [I-D.ietf-netconf-tls-client-server].¶
<CODE BEGINS> file "ietf-netconf-server@2023-12-28.yang"¶
module ietf-netconf-server { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-netconf-server"; prefix ncs; import ietf-yang-types { prefix yang; reference "RFC 6991: Common YANG Data Types"; } import ietf-x509-cert-to-name { prefix x509c2n; reference "RFC 7407: A YANG Data Model for SNMP Configuration"; } import ietf-tcp-client { prefix tcpc; reference "RFC DDDD: YANG Groupings for TCP Clients and TCP Servers"; } import ietf-tcp-server { prefix tcps; reference "RFC DDDD: YANG Groupings for TCP Clients and TCP Servers"; } import ietf-ssh-common { prefix sshcmn; reference "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers"; } import ietf-ssh-server { prefix sshs; reference "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers"; } import ietf-tls-server { prefix tlss; reference "RFC FFFF: YANG Groupings for TLS Clients and TLS Servers"; } organization "IETF NETCONF (Network Configuration) Working Group"; contact "WG Web: https://datatracker.ietf.org/wg/netconf WG List: NETCONF WG list <mailto:netconf@ietf.org> Author: Kent Watsen <mailto:kent+ietf@watsen.net>"; description "This module contains a collection of YANG definitions for configuring NETCONF servers. 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 HHHH (https://www.rfc-editor.org/info/rfcHHHH); see the RFC itself for full legal notices. The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document are to be interpreted as described in BCP 14 (RFC 2119) (RFC 8174) when, and only when, they appear in all capitals, as shown here."; revision 2023-12-28 { description "Initial version"; reference "RFC HHHH: NETCONF Client and Server Models"; } // Features feature ssh-listen { description "The 'ssh-listen' feature indicates that the NETCONF server supports opening a port to accept NETCONF over SSH client connections."; reference "RFC 6242: Using the NETCONF Protocol over Secure Shell (SSH)"; } feature tls-listen { description "The 'tls-listen' feature indicates that the NETCONF server supports opening a port to accept NETCONF over TLS client connections."; reference "RFC 7589: Using the NETCONF Protocol over Transport Layer Security (TLS) with Mutual X.509 Authentication"; } feature ssh-call-home { description "The 'ssh-call-home' feature indicates that the NETCONF server supports initiating a NETCONF over SSH call home connection to NETCONF clients."; reference "RFC 8071: NETCONF Call Home and RESTCONF Call Home"; } feature tls-call-home { description "The 'tls-call-home' feature indicates that the NETCONF server supports initiating a NETCONF over TLS call home connection to NETCONF clients."; reference "RFC 8071: NETCONF Call Home and RESTCONF Call Home"; } feature central-netconf-server-supported { description "The 'central-netconf-server-supported' feature indicates that the server supports the top-level 'netconf-server' node. This feature is needed as some servers may want to use features defined in this module, which requires this module to be implemented, without having to support the top-level 'netconf-server' node."; } // Groupings grouping netconf-server-grouping { description "A reusable grouping for configuring a NETCONF server without any consideration for how underlying transport sessions are established. Note that this grouping uses a fairly typical descendant node name such that a stack of 'uses' statements will have name conflicts. It is intended that the consuming data model will resolve the issue by wrapping the 'uses' statement in a container called, e.g., 'netconf-server-parameters'. This model purposely does not do this itself so as to provide maximum flexibility to consuming models."; container client-identity-mappings { description "Specifies mappings through which NETCONF client X.509 certificates are used to determine a NETCONF username, per RFC 7407. For TLS-based transports, if no matching and valid cert-to-name list entry can be found, then the NETCONF server MUST close the connection, and MUST NOT accept NETCONF messages over it, per Section 7 in RFC 7589. For SSH-based transports, a matching cert-to-name entry overrides the username provided by the SSH implementation, consistent with the second paragraph of Section 3 in RFC 6242."; reference "RFC 6242: Using the NETCONF Protocol over Secure Shell (SSH) RFC 7589: Using the NETCONF Protocol over Transport Layer Security (TLS) with Mutual X.509 Authentication"; uses x509c2n:cert-to-name { refine "cert-to-name/fingerprint" { mandatory false; description "A 'fingerprint' value does not need to be specified when the 'cert-to-name' mapping is independent of fingerprint matching. A 'cert-to-name' having no fingerprint value will match any client certificate and therefore should only be present at the end of the user-ordered 'cert-to-name' list."; } } } } grouping netconf-server-listen-stack-grouping { description "A reusable grouping for configuring a NETCONF server 'listen' protocol stack for listening on a single port."; choice transport { mandatory true; description "Selects between available transports."; case ssh { if-feature "ssh-listen"; container ssh { description "TCP, SSH, and NETCONF configuration to listen for NETCONF over SSH connections."; container tcp-server-parameters { description "TCP-level server parameters to listen for NETCONF over SSH connections."; uses tcps:tcp-server-grouping { refine "local-port" { default "830"; description "The NETCONF server will listen on the IANA-assigned well-known port value for 'netconf-ssh' (830) if no value is specified."; } } } container ssh-server-parameters { description "SSH-level server parameters to listen for NETCONF over SSH connections."; uses sshs:ssh-server-grouping; } container netconf-server-parameters { description "NETCONF-level server parameters to listen for NETCONF over SSH connections."; uses ncs:netconf-server-grouping { refine "client-identity-mappings" { if-feature "sshcmn:ssh-x509-certs"; description "Adds in an 'if-feature' statement ensuring the 'client-identity-mappings' descendant is enabled only when SSH supports X.509 certificates."; } augment "client-identity-mappings" { description "Adds a flag indicating if a cert-to-name is required."; leaf mapping-required { type boolean; description "Indicates that the cert-to-name mapping is required (i.e., the SSH-level username is ignored)."; } } } } } } case tls { if-feature "tls-listen"; container tls { description "TCP, TLS, and NETCONF configuration to listen for NETCONF over TLS connections."; container tcp-server-parameters { description "TCP-level server parameters to listen for NETCONF over TLS connections."; uses tcps:tcp-server-grouping { refine "local-port" { default "6513"; description "The NETCONF server will listen on the IANA-assigned well-known port value for 'netconf-tls' (6513) if no value is specified."; } } } container tls-server-parameters { description "TLS-level server parameters to listen for NETCONF over TLS connections."; uses tlss:tls-server-grouping { refine "client-authentication" { must 'ca-certs or ee-certs'; description "NETCONF/TLS servers MUST validate client certificates. This configures certificates at the socket-level (i.e. bags). More discriminating client-certificate checks SHOULD be implemented by the application."; reference "RFC 7589: Using the NETCONF Protocol over Transport Layer Security (TLS) with Mutual X.509 Authentication"; } } } container netconf-server-parameters { description "NETCONF-level server parameters to listen for NETCONF over TLS connections."; uses ncs:netconf-server-grouping { refine "client-identity-mappings/cert-to-name" { min-elements 1; description "The TLS transport requires a mapping."; } } } } } } } grouping netconf-server-callhome-stack-grouping { description "A reusable grouping for configuring a NETCONF server 'call-home' protocol stack, for a single outbound connection."; choice transport { mandatory true; description "Selects between available transports."; case ssh { if-feature "ssh-call-home"; container ssh { description "TCP, SSH, and NETCONF configuration to initiate a NETCONF over SSH Call Home connection."; container tcp-client-parameters { description "TCP-level client parameters to initiate a NETCONF over SSH Call Home connection."; uses tcpc:tcp-client-grouping { refine "remote-port" { default "4334"; description "The NETCONF server will attempt to connect to the IANA-assigned well-known port for 'netconf-ch-ssh' (4334) if no value is specified."; } } } container ssh-server-parameters { description "SSH-level server parameters to initiate a NETCONF over SSH Call Home connection."; uses sshs:ssh-server-grouping; } container netconf-server-parameters { description "NETCONF-level server parameters to initiate a NETCONF over SSH Call Home connection."; uses ncs:netconf-server-grouping { refine "client-identity-mappings" { if-feature "sshcmn:ssh-x509-certs"; description "Adds in an 'if-feature' statement ensuring the 'client-identity-mappings' descendant is enabled only when SSH supports X.509 certificates."; } augment "client-identity-mappings" { description "Adds a flag indicating if a cert-to-name is required."; leaf mapping-required { type boolean; description "Indicates that the cert-to-name mapping is required (i.e., the SSH-level username is ignored)."; } } } } } } case tls { if-feature "tls-call-home"; container tls { description "TCP, TLS, and NETCONF configuration to initiate a NETCONF over TLS Call Home connection."; container tcp-client-parameters { description "TCP-level client parameters to initiate a NETCONF over TLS Call Home connection."; uses tcpc:tcp-client-grouping { refine "remote-port" { default "4335"; description "The NETCONF server will attempt to connect to the IANA-assigned well-known port for 'netconf-ch-tls' (4335) if no value is specified."; } } } container tls-server-parameters { description "TLS-level server parameters to initiate a NETCONF over TLS Call Home connection."; uses tlss:tls-server-grouping { refine "client-authentication" { must 'ca-certs or ee-certs'; description "NETCONF/TLS servers MUST validate client certificates. This configures certificates at the socket-level (i.e. bags). More discriminating client-certificate checks SHOULD be implemented by the application."; reference "RFC 7589: Using the NETCONF Protocol over Transport Layer Security (TLS) with Mutual X.509 Authentication"; } } } container netconf-server-parameters { description "NETCONF-level server parameters to initiate a NETCONF over TLS Call Home connection."; uses ncs:netconf-server-grouping { refine "client-identity-mappings/cert-to-name" { min-elements 1; description "The TLS transport requires a mapping."; } } } } } } } grouping netconf-server-app-grouping { description "A reusable grouping for configuring a NETCONF server application that supports both 'listen' and 'call-home' protocol stacks for a multiplicity of connections."; container listen { if-feature "ssh-listen or tls-listen"; presence "Indicates that server-listening ports have been configured. This statement is present so the mandatory descendant nodes do not imply that this node must be configured."; description "Configures listen behavior"; leaf idle-timeout { type uint16; units "seconds"; default "180"; // three minutes description "Specifies the maximum number of seconds that a NETCONF session may remain idle. A NETCONF session will be dropped if it is idle for an interval longer than this number of seconds. If set to zero, then the server will never drop a session because it is idle."; } container endpoints { description "Container for a list of endpoints."; list endpoint { key "name"; min-elements 1; description "List of endpoints to listen for NETCONF connections."; leaf name { type string; description "An arbitrary name for the NETCONF listen endpoint."; } uses netconf-server-listen-stack-grouping; } } } container call-home { if-feature "ssh-call-home or tls-call-home"; presence "Indicates that server-initiated call home connections have been configured. This statement is present so the mandatory descendant nodes do not imply that this node must be configured."; description "Configures the NETCONF server to initiate the underlying transport connection to NETCONF clients."; list netconf-client { key "name"; min-elements 1; description "List of NETCONF clients the NETCONF server is to maintain simultaneous call-home connections with."; leaf name { type string; description "An arbitrary name for the remote NETCONF client."; } container endpoints { description "Container for the list of endpoints."; list endpoint { key "name"; min-elements 1; ordered-by user; description "A non-empty user-ordered list of endpoints for this NETCONF server to try to connect to in sequence. Defining more than one enables high-availability."; leaf name { type string; description "An arbitrary name for this endpoint."; } uses netconf-server-callhome-stack-grouping; } } container connection-type { description "Indicates the NETCONF server's preference for how the NETCONF connection is maintained."; choice connection-type { mandatory true; description "Selects between available connection types."; case persistent-connection { container persistent { presence "Indicates that a persistent connection is to be maintained."; description "Maintain a persistent connection to the NETCONF client. If the connection goes down, immediately start trying to reconnect to the NETCONF client, using the reconnection strategy. This connection type minimizes any NETCONF client to NETCONF server data-transfer delay, albeit at the expense of holding resources longer."; } } case periodic-connection { container periodic { presence "Indicates that a periodic connection is to be maintained."; description "Periodically connect to the NETCONF client. This connection type decreases resource utilization, albeit with increased delay in NETCONF client to NETCONF server interactions. The NETCONF client SHOULD gracefully close the connection using <close-session> upon completing planned activities. If the NETCONF session is not closed gracefully, the NETCONF server MUST immediately attempt to reestablish the connection. Connections are established at the same start time regardless how long the previous connection stayed open. In the case that the previous connection is still active (i.e., the NETCONF client has not closed it yet), establishing a new connection is NOT RECOMMENDED."; leaf period { type uint16; units "minutes"; default "60"; description "Duration of time between periodic connections."; } leaf anchor-time { type yang:date-and-time { // constrained to minute-level granularity pattern '[0-9]{4}-(1[0-2]|0[1-9])-(0[1-9]|[1-2]' + '[0-9]|3[0-1])T(0[0-9]|1[0-9]|2[0-3]):[' + '0-5][0-9]:00(Z|[\+\-]((1[0-3]|0[0-9]):' + '([0-5][0-9])|14:00))?'; } description "Designates a timestamp before or after which a series of periodic connections are determined. The periodic connections occur at a whole multiple interval from the anchor time. If an 'anchor-time' is not provided, then the server may implicitly set it to the time when this configuraton is applied (e.g., on boot). For example, for an anchor time is 15 minutes past midnight and a period interval of 24 hours, then a periodic connection will occur 15 minutes past midnight everyday."; } leaf idle-timeout { type uint16; units "seconds"; default "180"; // three minutes description "Specifies the maximum number of seconds that a NETCONF session may remain idle. A NETCONF session will be dropped if it is idle for an interval longer than this number of seconds. If set to zero, then the server will never drop a session because it is idle."; } } } // case periodic-connection } // choice connection-type } // container connection-type container reconnect-strategy { description "The reconnection strategy directs how a NETCONF server reconnects to a NETCONF client, after discovering its connection to the client has dropped, even if due to a reboot. The NETCONF server starts with the specified endpoint and tries to connect to it max-attempts times before trying the next endpoint in the list (round robin)."; leaf start-with { type enumeration { enum first-listed { description "Indicates that reconnections should start with the first endpoint listed."; } enum last-connected { description "Indicates that reconnections should start with the endpoint last connected to. If no previous connection has ever been established, then the first endpoint configured is used. NETCONF servers SHOULD be able to remember the last endpoint connected to across reboots."; } enum random-selection { description "Indicates that reconnections should start with a random endpoint."; } } default "first-listed"; description "Specifies which of the NETCONF client's endpoints the NETCONF server should start with when trying to connect to the NETCONF client."; } leaf max-wait { type uint16 { range "1..max"; } units "seconds"; default "5"; description "Specifies the amount of time in seconds after which, if the connection is not established, an endpoint connection attempt is considered unsuccessful."; } leaf max-attempts { type uint8 { range "1..max"; } default "3"; description "Specifies the number times the NETCONF server tries to connect to a specific endpoint before moving on to the next endpoint in the list (round robin)."; } } // container reconnect-strategy } // list netconf-client } // container call-home } // grouping netconf-server-app-grouping // Protocol accessible node for servers that implement this module. container netconf-server { if-feature central-netconf-server-supported; uses netconf-server-app-grouping; description "Top-level container for NETCONF server configuration."; } }¶
<CODE ENDS>¶
The "ietf-netconf-client" YANG module defines data nodes that are designed to be accessed via YANG based management protocols, such as NETCONF [RFC6241] and RESTCONF [RFC8040]. Both of these protocols have mandatory-to-implement secure transport layers (e.g., SSH, TLS) with mutual authentication.¶
The Network Access Control Model (NACM) [RFC8341] provides the means to restrict access for particular users to a pre-configured subset of all available protocol operations and content.¶
Please be aware that this YANG module uses groupings from other YANG modules that define nodes that may be considered sensitive or vulnerable in network environments. Please review the Security Considerations for dependent YANG modules for information as to which nodes may be considered sensitive or vulnerable in network environments.¶
None of the readable data nodes defined in this YANG module are considered sensitive or vulnerable in network environments. The NACM "default-deny-all" extension has not been set for any data nodes defined in this module.¶
None of the writable data nodes defined in this YANG module are considered sensitive or vulnerable in network environments. The NACM "default-deny-write" extension has not been set for any data nodes defined in this module.¶
This module does not define any RPCs, actions, or notifications, and thus the security consideration for such is not provided here.¶
Please be aware that this module uses groupings defined in other RFCs that define data nodes that do set the NACM "default-deny-all" and "default-deny-write" extensions.¶
The "ietf-netconf-server" YANG module defines data nodes that are designed to be accessed via YANG based management protocols, such as NETCONF [RFC6241] and RESTCONF [RFC8040]. Both of these protocols have mandatory-to-implement secure transport layers (e.g., SSH, TLS) with mutual authentication.¶
The Network Access Control Model (NACM) [RFC8341] provides the means to restrict access for particular users to a pre-configured subset of all available protocol operations and content.¶
Please be aware that this YANG module uses groupings from other YANG modules that define nodes that may be considered sensitive or vulnerable in network environments. Please review the Security Considerations for dependent YANG modules for information as to which nodes may be considered sensitive or vulnerable in network environments.¶
None of the readable data nodes defined in this YANG module are considered sensitive or vulnerable in network environments. The NACM "default-deny-all" extension has not been set for any data nodes defined in this module.¶
None of the writable data nodes defined in this YANG module are considered sensitive or vulnerable in network environments. The NACM "default-deny-write" extension has not been set for any data nodes defined in this module.¶
This module does not define any RPCs, actions, or notifications, and thus the security consideration for such is not provided here.¶
Please be aware that this module uses groupings defined in other RFCs that define data nodes that do set the NACM "default-deny-all" and "default-deny-write" extensions.¶
This document registers two URIs in the "ns" subregistry of the IETF XML Registry [RFC3688]. Following the format in [RFC3688], the following registrations are requested:¶
URI: urn:ietf:params:xml:ns:yang:ietf-netconf-client Registrant Contact: The IESG XML: N/A, the requested URI is an XML namespace. URI: urn:ietf:params:xml:ns:yang:ietf-netconf-server Registrant Contact: The IESG XML: N/A, the requested URI is an XML namespace.¶
This document registers two YANG modules in the YANG Module Names registry [RFC6020]. Following the format in [RFC6020], the following registrations are requested:¶
name: ietf-netconf-client namespace: urn:ietf:params:xml:ns:yang:ietf-netconf-client prefix: ncc reference: RFC HHHH name: ietf-netconf-server namespace: urn:ietf:params:xml:ns:yang:ietf-netconf-server prefix: ncs reference: RFC HHHH¶
This section is to be removed before publishing as an RFC.¶
The authors would like to thank for following for lively discussions on list and in the halls (ordered by first name): Alan Luchuk, Andy Bierman, Balázs Kovács, Benoit Claise, Bert Wijnen, David Lamparter, Juergen Schoenwaelder, Ladislav Lhotka, Martin Björklund, Mehmet Ersue, Michal Vaško, Phil Shafer, Qiufang Ma, Radek Krejci, Ramkumar Dhanapal, Sean Turner, and Tom Petch.¶