module ietf-netconf-server {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-netconf-server";
prefix "ncs";
import ietf-inet-types {
prefix inet;
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-ssh-server {
prefix ss;
revision-date 2016-07-08; // stable grouping definitions
reference
"RFC YYYY: SSH Client and Server Models";
}
import ietf-tls-server {
prefix ts;
revision-date 2016-07-08; // stable grouping definitions
reference
"RFC ZZZZ: TLS Client and Server Models";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web:
WG List:
WG Chair: Mehmet Ersue
WG Chair: Mahesh Jethanandani
Editor: Kent Watsen
";
description
"This module contains a collection of YANG definitions for
configuring NETCONF servers.
Copyright (c) 2014 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 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 "2016-07-08" {
description
"Initial version";
reference
"RFC XXXX: NETCONF Client and Server Models";
}
// Features
feature listen {
description
"The 'listen' feature indicates that the NETCONF server
supports opening a port to accept NETCONF client connections
using at least one transport (e.g., SSH, TLS, etc.).";
}
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 call-home {
description
"The 'call-home' feature indicates that the NETCONF server
supports initiating NETCONF call home connections to NETCONF
clients using at least one transport (e.g., SSH, TLS, etc.).";
reference
"RFC YYYY: NETCONF Call Home and RESTCONF Call Home";
}
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 YYYY: 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 YYYY: NETCONF Call Home and RESTCONF Call Home";
}
// top-level container (groupings below)
container netconf-server {
description
"Top-level container for NETCONF server configuration.";
container session-options { // SHOULD WE REMOVE THIS ALTOGETHER?
description
"NETCONF session options, independent of transport
or connection strategy.";
leaf hello-timeout {
type uint16;
units "seconds";
default 600;
description
"Specifies the maximum number of seconds that a SSH/TLS
connection may wait for a hello message to be received.
A connection will be dropped if no hello message is
received before this number of seconds elapses. If set
to zero, then the server will wait forever for a hello
message.";
}
}
container listen {
if-feature listen;
description
"Configures listen behavior";
leaf max-sessions {
type uint16;
default 0;
description
"Specifies the maximum number of concurrent sessions
that can be active at one time. The value 0 indicates
that no artificial session limit should be used.";
}
leaf idle-timeout {
type uint16;
units "seconds";
default 3600; // one hour
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. Sessions that have a
notification subscription active are never dropped.";
}
list endpoint {
key name;
description
"List of endpoints to listen for NETCONF connections on.";
leaf name {
type string;
description
"An arbitrary name for the NETCONF listen endpoint.";
}
choice transport {
mandatory true;
description
"Selects between available transports.";
case ssh {
if-feature ssh-listen;
container ssh {
description
"SSH-specific listening configuration for inbound
connections.";
uses ss:listening-ssh-server-grouping {
refine port {
default 830;
}
}
}
}
case tls {
if-feature tls-listen;
container tls {
description
"TLS-specific listening configuration for inbound
connections.";
uses ts:listening-tls-server-grouping {
refine port {
default 6513;
}
augment "client-auth" {
description
"Augments in the cert-to-name structure.";
uses cert-maps-grouping;
}
}
}
}
}
}
}
container call-home {
if-feature call-home;
description
"Configures call-home behavior";
list netconf-client {
key name;
description
"List of NETCONF clients the NETCONF server is to initiate
call-home connections to.";
leaf name {
type string;
description
"An arbitrary name for the remote NETCONF client.";
}
choice transport {
mandatory true;
description
"Selects between available transports.";
case ssh {
if-feature ssh-call-home;
container ssh {
description
"Specifies SSH-specific call-home transport
configuration.";
uses endpoints-container {
refine endpoints/endpoint/port {
default 4334;
}
}
uses ss:non-listening-ssh-server-grouping;
}
}
case tls {
if-feature tls-call-home;
container tls {
description
"Specifies TLS-specific call-home transport
configuration.";
uses endpoints-container {
refine endpoints/endpoint/port {
default 4335;
}
}
uses ts:non-listening-tls-server-grouping {
augment "client-auth" {
description
"Augments in the cert-to-name structure.";
uses cert-maps-grouping;
}
}
}
}
}
container connection-type {
description
"Indicates the kind of connection to use.";
choice connection-type {
description
"Selects between available connection types.";
case persistent-connection {
container persistent {
presence true;
description
"Maintain a persistent connection to the NETCONF
client. If the connection goes down, immediately
start trying to reconnect to it, 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.";
leaf idle-timeout {
type uint32;
units "seconds";
default 86400; // one day;
description
"Specifies the maximum number of seconds that a
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. Sessions that
have a notification subscription active are
never dropped.";
}
container keep-alives {
description
"Configures the keep-alive policy, to proactively
test the aliveness of the SSH/TLS client. An
unresponsive SSH/TLS client will be dropped after
approximately max-attempts * max-wait seconds.";
reference
"RFC YYYY: NETCONF Call Home and RESTCONF Call
Home, Section 3.1, item S6";
leaf max-wait {
type uint16 {
range "1..max";
}
units seconds;
default 30;
description
"Sets the amount of time in seconds after which
if no data has been received from the SSH/TLS
client, a SSH/TLS-level message will be sent
to test the aliveness of the SSH/TLS client.";
}
leaf max-attempts {
type uint8;
default 3;
description
"Sets the maximum number of sequential keep-alive
messages that can fail to obtain a response from
the SSH/TLS client before assuming the SSH/TLS
client is no longer alive.";
}
}
}
}
case periodic-connection {
container periodic {
presence true;
description
"Periodically connect to the NETCONF client, so that
the NETCONF client may deliver messages pending for
the NETCONF server. The NETCONF client must close
the connection when it is ready to release it. Once
the connection has been closed, the NETCONF server
will restart its timer until the next connection.";
leaf idle-timeout {
type uint16;
units "seconds";
default 300; // five minutes
description
"Specifies the maximum number of seconds that a
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. Sessions that
have a notification subscription active are
never dropped.";
}
leaf reconnect_timeout {
type uint16 {
range "1..max";
}
units minutes;
default 60;
description
"Sets the maximum amount of unconnected time the
NETCONF server will wait before re-establishing
a connection to the NETCONF client. The NETCONF
server may initiate a connection before this
time if desired (e.g., to deliver an event
notification message).";
}
}
}
}
}
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.";
}
}
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-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).";
}
}
}
}
}
grouping cert-maps-grouping {
description
"A grouping that defines a container around the
cert-to-name structure defined in RFC 7407.";
container cert-maps {
uses x509c2n:cert-to-name;
description
"The cert-maps container is used by a TLS-based NETCONF
server to map the NETCONF client's presented X.509
certificate to a NETCONF username. 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.";
reference
"RFC WWWW: NETCONF over TLS, Section 7";
}
}
grouping endpoints-container {
description
"This grouping is used by both the ssh and tls containers
for call-home configurations.";
container endpoints {
description
"Container for the list of endpoints.";
list endpoint {
key name;
min-elements 1;
ordered-by user;
description
"User-ordered list of endpoints for this NETCONF client.
Defining more than one enables high-availability.";
leaf name {
type string;
description
"An arbitrary name for this endpoint.";
}
leaf address {
type inet:host;
mandatory true;
description
"The IP address or hostname of the endpoint. If a
hostname is configured and the DNS resolution results
in more than one IP address, the NETCONF server
will process the IP addresses as if they had been
explicitly configured in place of the hostname.";
}
leaf port {
type inet:port-number;
description
"The IP port for this endpoint. The NETCONF server will
use the IANA-assigned well-known port if no value is
specified.";
}
}
}
}
}