A YANG Data Model for Syslog ManagementCiscoUnited States of Americajclarke@cisco.comKloud ServicesUnited States of Americamjethanandani@gmail.comCisco Systems Inc.170 West Tasman DriveSan JoseCA95134United States of America+1 415 819-6111clyde@clydewildes.comVerizon Wireless500 W Dove Rd.SouthlakeTX76092United States of America+1 512 650-0210kirankoushik.agraharasreenivasa@verizonwireless.com
OPS
netmod
This document defines a YANG data model for the management of a syslog
process. It is intended that this data model be used by vendors who implement
syslog collectors in their systems.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by
the Internet Engineering Steering Group (IESG). Further
information on Internet Standards is available in Section 2 of
RFC 7841.
Information about the current status of this document, any
errata, and how to provide feedback on it may be obtained at
.
Copyright Notice
Copyright (c) 2025 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
() in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with
respect to this document. Code Components extracted from this
document must include Revised BSD License text as described in
Section 4.e of the Trust Legal Provisions and are provided without
warranty as described in the Revised BSD License.
Table of Contents
. Introduction
. Requirements Language
. Terminology
. NMDA Compliance
. Design of the Syslog Model
. Syslog Module
. Syslog YANG Module
. The ietf-syslog Module
. Usage Examples
. Syslog Configuration for Severity Critical
. Remote Syslog Configuration
. IANA Considerations
. The IETF XML Registry
. The YANG Module Names Registry
. Security Considerations
. References
. Normative References
. Informative References
. Tree Diagrams
. Complete Tree Diagram
. Implementer Guidelines
. Extending Facilities
. Syslog Terminal Output
. Syslog File Naming Convention
Acknowledgements
Authors' Addresses
IntroductionThis document defines a YANG data model that
may be used to configure the syslog feature running on a system. YANG
data models can be used with network management protocols such as NETCONF
to install, manipulate, and delete the
configuration of network devices.The data model makes use of the YANG "feature" construct that allows
implementations to support only those syslog features that lie within
their capabilities.
This module can be used to configure the syslog application
conceptual layers as implemented on the syslog collector.
Essentially, a syslog process receives messages (from the kernel,
processes, applications, or other syslog processes) and processes them.
The processing may involve logging to a local file, displaying on
console, and/or relaying to syslog processes on other machines. The
process is determined by the "facility" that originated the message
and the "severity" assigned to the message by the facility.Such definitions of syslog protocol are defined in
and are used in this RFC.The YANG data model in this document conforms to the Network Management
Datastore Architecture defined in .Requirements Language
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 when, and only when, they appear in all capitals,
as shown here.
Terminology
The following terms are used throughout this document:
Originator:
An "originator" refers to an entity that generates
syslog content to be carried in a message. The term is defined
in .
Relay:
A "relay" is an entity that forwards syslog messages. It
accepts messages from originators or other relays and sends them
to collectors or other relays. The term is defined in .
Collector:
A "collector" gathers syslog content for
further analysis. The term is defined in .
Action:
The term "action" refers to the process that takes
place for each syslog message received.
NMDA ComplianceThe YANG data model in this document conforms to the Network Management
Datastore Architecture (NMDA) defined in
.
Design of the Syslog Model
The syslog model was designed by comparing various syslog features
implemented by various vendors in different implementations.
The module defines leafs that are common across
implementations. Its simple design is meant to offer maximum
flexibility. However, not all optional features defined in this
document are present in all vendor implementations. Therefore, vendors
need to use the feature statements to specify the
optional features they support. At the same time, vendors can
augment the model to add proprietary features. "Extending
Facilities" () shows an
example of how that can be realized.
Syslog consists of originators and collectors. The following diagram
shows the syslog processing flow from originators to collectors where
filtering can take place.Syslog Processing Flow
Originators
+-------------+ +-------------+ +-------------+ +-------------+
| Various | | OS | | | | Remote |
| Components | | Kernel | | Line Cards | | Servers |
+-------------+ +-------------+ +-------------+ +-------------+
+-------------+ +-------------+ +-------------+ +-------------+
| SNMP | | Interface | | Standby | | Syslog |
| Events | | Events | | Supervisor | | Itself |
+-------------+ +-------------+ +-------------+ +-------------+
| |
+----------------------------------------------------------------+
|
|
|
|
+-------------+--------------+
| | |
v v v
Collectors
+----------+ +----------+ +----------------+
| | | Log | |Remote Relay(s)/|
| Console | | File(s) | |Collector(s) |
+----------+ +----------+ +----------------+Collectors are configured using the leafs in the syslog model
"actions" container that correspond to each message collector:
console
log file(s)
remote relay(s)/collector(s)
Within each action, a selector is used to filter syslog messages. A
selector consists of a list of one or more filters specified by
facility-severity pairs, and, if supported via the select-match
feature, an optional regular expression pattern match that is
performed on the MSG field described in .
A syslog message is processed if there is an element
of facility-list (F, S) where
the message facility matches F,
the message severity matches S,
and/or the message text matches the regex pattern (if it
is present)The facility is one of a specific syslog-facility or all
facilities.
The model offers the ability to select a transport that a user
might want to use for a remote relay or collector. The choice
is between using UDP or TLS-based sessions. The user can
configure multiple relays or collectors, but they have to use
the same transport.
The severity is one of type syslog-severity, all severities, or none.
None is a special case that can be used to disable a filter. When
filtering severity, the default comparison is that messages of the
specified severity and higher are selected to be logged. This is shown
in the model as "default equals-or-higher". This behavior can be altered
if the select-adv-compare feature is enabled to specify a compare
operation and an action. Compare operations are: "equals" to select
messages with this single severity, or "equals-or-higher" to select
messages of the specified severity and higher. Actions are used to log
the message, block the message, or stop the message from being logged.
Many vendors extend the list of facilities available for
logging in their implementation. An example is included in "Extending Facilities"
().
Syslog Module
A simplified tree representation of the data model is shown in . Please see for tree
diagram notation.
Tree Diagram for Syslog Model
module: ietf-syslog
+--rw syslog!
+--rw actions
+--rw console! {console-action}?
| +--rw filter
| | +--rw facility-list* [facility severity]
| | +--rw facility union
| | +--rw severity union
| | +--rw advanced-compare {select-adv-compare}?
| | +--rw compare? enumeration
| | +--rw action? identityref
| +--rw pattern-match? string {select-match}?
+--rw file {file-action}?
| +--rw log-file* [name]
| +--rw name inet:uri
| +--rw filter
| | +--rw facility-list* [facility severity]
| | +--rw facility union
| | +--rw severity union
| | +--rw advanced-compare {select-adv-compare}?
| | +--rw compare? enumeration
| | +--rw action? identityref
| +--rw pattern-match? string {select-match}?
| +--rw structured-data? boolean {structured-data}?
| +--rw file-rotation
| +--rw number-of-files? uint32 {file-limit-size}?
| +--rw max-file-size? uint32 {file-limit-size}?
| +--rw rollover? uint32
| | {file-limit-duration}?
| +--rw retention? uint32
| {file-limit-duration}?
+--rw remote {remote-action}?
+--rw destination* [name]
+--rw name string
+--rw (transport)
| +--:(udp)
| | +--rw udp
| | +--rw udp* [address]
| | +--rw address inet:host
| | +--rw port? inet:port-number
| +--:(tls)
| +--rw tls
| +--rw tls* [address]
| +--rw address inet:host
| +--rw port?
| | inet:port-number
| +--rw client-identity!
| | +--rw (auth-type)
| | ...
| +--rw server-authentication
| | +--rw ca-certs! {server-auth-x509-cert}?
| | | ...
| | +--rw ee-certs! {server-auth-x509-cert}?
| | | ...
| | +--rw raw-public-keys!
| | | {server-auth-raw-public-key}?
| | | ...
| | +--rw tls12-psks? empty
| | | {server-auth-tls12-psk}?
| | +--rw tls13-epsks? empty
| | {server-auth-tls13-epsk}?
| +--rw hello-params {tlscmn:hello-params}?
| | +--rw tls-versions
| | | ...
| | +--rw cipher-suites
| | ...
| +--rw keepalives {tls-client-keepalives}?
| +--rw peer-allowed-to-send? empty
| +--rw test-peer-aliveness!
| ...
+--rw filter
| +--rw facility-list* [facility severity]
| +--rw facility union
| +--rw severity union
| +--rw advanced-compare {select-adv-compare}?
| +--rw compare? enumeration
| +--rw action? identityref
+--rw pattern-match? string {select-match}?
+--rw structured-data? boolean {structured-data}?
+--rw facility-override? identityref
+--rw source-interface? if:interface-ref
| {remote-source-interface}?
+--rw signing! {signed-messages}?
+--rw cert-signers
+--rw cert-signer* [name]
| +--rw name string
| +--rw cert
| | +--rw public-key-format?
| | | identityref
| | +--rw public-key? binary
| | +--rw private-key-format?
| | | identityref
| | +--rw (private-key-type)
| | | +--:(cleartext-private-key)
| | | | {cleartext-private-keys}?
| | | | ...
| | | +--:(hidden-private-key)
| | | | {hidden-private-keys}?
| | | | ...
| | | +--:(encrypted-private-key)
| | | {encrypted-private-keys}?
| | | ...
| | +--rw cert-data?
| | | end-entity-cert-cms
| | +---n certificate-expiration
| | | {certificate-expiration-notificati\
on}?
| | | +-- expiration-date
| | | yang:date-and-time
| | +---x generate-csr {csr-generation}?
| | +---w input
| | | ...
| | +--ro output
| | ...
| +--rw hash-algorithm? enumeration
+--rw cert-initial-repeat? uint32
+--rw cert-resend-delay? uint32
+--rw cert-resend-count? uint32
+--rw sig-max-delay? uint32
+--rw sig-number-resends? uint32
+--rw sig-resend-delay? uint32
+--rw sig-resend-count? uint32
Syslog YANG ModuleThe ietf-syslog Module
This module imports typedefs from , , groupings from , and . It references
, , , , , , and .
Syslog YANG Module
module ietf-syslog {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-syslog";
prefix syslog;
import ietf-inet-types {
prefix inet;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-interfaces {
prefix if;
reference
"RFC 8343: A YANG Data Model for Interface Management";
}
import ietf-tls-client {
prefix tlsc;
reference
"RFC 9645: YANG Groupings for TLS Clients and TLS Servers";
}
import ietf-crypto-types {
prefix ct;
reference
"RFC 9640: YANG Data Types and Groupings for Cryptography";
}
organization
"IETF NETMOD (Network Modeling) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/netmod/>
WG List: <mailto:netmod@ietf.org>
Editor: Mahesh Jethanandani
<mailto:mjethanandani@gmail.com>
Editor: Joe Clarke
<mailto:jclarke@cisco.com>
Editor: Kiran Agrahara Sreenivasa
<mailto:kirankoushik.agraharasreenivasa@verizonwireless.com>
Editor: Clyde Wildes
<mailto:clyde@clydewildes.com>";
description
"This module contains a collection of YANG definitions
for syslog management.
Copyright (c) 2025 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 9742
(https://www.rfc-editor.org/info/rfc9742);
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 2025-04-30 {
description
"Initial Revision";
reference
"RFC 9742: Syslog YANG Module";
}
feature console-action {
description
"This feature indicates that the local console action is
supported.";
}
feature file-action {
description
"This feature indicates that the local file action is
supported.";
}
feature file-limit-size {
description
"This feature indicates that file logging resources
are managed using size and number limits.";
}
feature file-limit-duration {
description
"This feature indicates that file logging resources
are managed using time based limits.";
}
feature remote-action {
description
"This feature indicates that the remote server action is
supported.";
}
feature remote-source-interface {
description
"This feature indicates that source-interface is supported
for the remote-action.";
}
feature select-adv-compare {
description
"This feature represents the ability to select messages
using the additional comparison operators when comparing
the syslog message severity.";
}
feature select-match {
description
"This feature represents the ability to select messages
based on a Posix 1003.2 regular expression pattern
match.";
}
feature structured-data {
description
"This feature represents the ability to log messages
in structured-data format.";
reference
"RFC 5424: The Syslog Protocol";
}
feature signed-messages {
description
"This feature represents the ability to configure signed
syslog messages.";
reference
"RFC 5848: Signed Syslog Messages";
}
typedef syslog-severity {
type enumeration {
enum emergency {
value 0;
description
"The severity level 'Emergency' indicates that the
system is unusable.";
}
enum alert {
value 1;
description
"The severity level 'Alert' indicates that an
action must be taken immediately.";
}
enum critical {
value 2;
description
"The severity level 'Critical' indicates a
critical condition.";
}
enum error {
value 3;
description
"The severity level 'Error' indicates an error
condition.";
}
enum warning {
value 4;
description
"The severity level 'Warning' indicates a warning
condition.";
}
enum notice {
value 5;
description
"The severity level 'Notice' indicates a normal
but significant condition.";
}
enum info {
value 6;
description
"The severity level 'Info' indicates an
informational message.";
}
enum debug {
value 7;
description
"The severity level 'Debug' indicates a
debug-level message.";
}
}
description
"The definitions for Syslog message severity.
Note that a lower value is a higher severity. Comparisons
of equal-or-higher severity mean equal-or-lower numeric
value";
reference
"RFC 5424: The Syslog Protocol";
}
identity syslog-facility {
description
"This identity is used as a base for all syslog
facilities.";
reference
"RFC 5424: The Syslog Protocol";
}
identity kern {
base syslog-facility;
description
"The facility for kernel messages (numerical code 0).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity user {
base syslog-facility;
description
"The facility for user-level messages (numerical code 1).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity mail {
base syslog-facility;
description
"The facility for the mail system (numerical code 2).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity daemon {
base syslog-facility;
description
"The facility for the system daemons (numerical code 3).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity auth {
base syslog-facility;
description
"The facility for security/authorization messages (numerical
code 4).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity syslog {
base syslog-facility;
description
"The facility for messages generated internally by a syslog
daemon facility (numerical code 5).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity lpr {
base syslog-facility;
description
"The facility for the line printer subsystem (numerical code
6).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity news {
base syslog-facility;
description
"The facility for the network news subsystem (numerical code
7).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity uucp {
base syslog-facility;
description
"The facility for the Unix-to-Unix Copy (UUCP) subsystem
(numerical code 8).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity cron {
base syslog-facility;
description
"The facility for the clock daemon (numerical code 9).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity authpriv {
base syslog-facility;
description
"The facility for privileged security/authorization messages
(numerical code 10).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity ftp {
base syslog-facility;
description
"The facility for the FTP daemon (numerical code 11).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity ntp {
base syslog-facility;
description
"The facility for the NTP subsystem (numerical code 12).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity audit {
base syslog-facility;
description
"The facility for log audit messages (numerical code 13).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity console {
base syslog-facility;
description
"The facility for log alert messages (numerical code 14).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity cron2 {
base syslog-facility;
description
"The facility for the second clock daemon (numerical code
15).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity local0 {
base syslog-facility;
description
"The facility for local use 0 messages (numerical code 16).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity local1 {
base syslog-facility;
description
"The facility for local use 1 messages (numerical code 17).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity local2 {
base syslog-facility;
description
"The facility for local use 2 messages (numerical code 18).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity local3 {
base syslog-facility;
description
"The facility for local use 3 messages (numerical code 19).";
reference
"RFC 5424: The Syslog Protocol";
}
identity local4 {
base syslog-facility;
description
"The facility for local use 4 messages (numerical code 20).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity local5 {
base syslog-facility;
description
"The facility for local use 5 messages (numerical code 21).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity local6 {
base syslog-facility;
description
"The facility for local use 6 messages (numerical code 22).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity local7 {
base syslog-facility;
description
"The facility for local use 7 messages (numerical code 23).";
reference
"RFC 5424: The Syslog Protocol, Section 6.2.1.";
}
identity action {
description
"Base identity for action for how a message will be
handled.";
}
identity log {
base action;
description
"This identity specifies that if the compare operation is
true, the message will be logged.";
}
identity block {
base action;
description
"This identity specifies that if the compare operation is
true, the message will not be logged.";
}
identity stop {
base action;
description
"This identity specifies that if the compare operation is
true, the message will not be logged and no further
processing will occur for it.";
}
grouping severity-filter {
description
"This grouping defines the processing used to select
log messages by comparing syslog message severity using
the following processing rules:
- if 'none', do not match.
- if 'all', match.
- else, compare message severity with the specified
severity according to the default compare rule (all
messages of the specified severity and greater match)
or if the select-adv-compare feature is present, use
the advance-compare rule.";
leaf severity {
type union {
type syslog-severity;
type enumeration {
enum none {
value 2147483647;
description
"This enum describes the case where no
severities are selected.";
}
enum all {
value -2147483648;
description
"This enum describes the case where all
severities are selected.";
}
}
}
mandatory true;
description
"This leaf specifies the syslog message severity.";
}
container advanced-compare {
when "../severity != \"all\" and
../severity != \"none\"" {
description
"The advanced compare container is not applicable
for severity 'all' or severity 'none'";
}
if-feature "select-adv-compare";
leaf compare {
type enumeration {
enum equals {
description
"This enum specifies that the severity
comparison operation will be equals.";
}
enum equals-or-higher {
description
"This enum specifies that the severity
comparison operation will be equals or
higher.";
}
}
default "equals-or-higher";
description
"The compare operation can be used to specify the comparison
operator that should be used to compare the syslog
message severity with the specified severity.";
}
leaf action {
type identityref {
base action;
}
default "log";
description
"The action can be used to specify how the message
should be handled. This may include logging the
message, not logging the message (i.e., blocking
it), or stopping further processing.";
}
description
"This container describes additional severity compare
operations that can be used in place of the default
severity comparison. The compare leaf specifies the
type of compare operation that is done and the
action leaf specifies the intended result.
Example: compare->equals and action->block means
messages that have a severity that are equal to the
specified severity will not be logged.";
}
}
grouping selector {
description
"This grouping defines a syslog selector, which is used to
select log messages for the log-actions (console, file,
remote, etc.). Choose one or both of the following:
facility [<facility> <severity>...]
pattern-match regular-expression-match-string
If both facility and pattern-match are specified, both
must match in order for a log message to be selected.";
container filter {
description
"This container describes the syslog filter
parameters.";
list facility-list {
key "facility severity";
ordered-by user;
description
"This list describes a collection of syslog
facilities and severities.";
leaf facility {
type union {
type identityref {
base syslog-facility;
}
type enumeration {
enum all {
description
"This enum describes the case where
all facilities are requested.";
}
}
}
description
"The leaf uniquely identifies a syslog
facility.";
}
uses severity-filter;
}
}
leaf pattern-match {
if-feature "select-match";
type string;
description
"This leaf describes a Posix 1003.2 regular expression
string that can be used to select a syslog message for
logging. The match is performed on the SYSLOG-MSG
field.";
reference
"RFC 5424: The Syslog Protocol
Std-1003.1-2024 Regular Expressions";
}
}
grouping structured-data {
description
"This grouping defines the syslog structured data option,
which is used to select the format used to write log
messages.";
leaf structured-data {
if-feature "structured-data";
type boolean;
default "false";
description
"This leaf describes how log messages are written.
If true, messages will be written with one or more
STRUCTURED-DATA elements; if false, messages will be
written with STRUCTURED-DATA = NILVALUE.";
reference
"RFC 5424: The Syslog Protocol";
}
}
container syslog {
presence "Enables logging.";
description
"This container describes the configuration parameters for
syslog.";
container actions {
description
"This container describes the log-action parameters
for syslog.";
container console {
if-feature "console-action";
presence "Enables logging to the console";
description
"This container describes the configuration
parameters for console logging.";
uses selector;
}
container file {
if-feature "file-action";
description
"This container describes the configuration
parameters for file logging. If file-archive
limits are not supplied, it is assumed that
the local implementation defined limits will
be used.";
list log-file {
key "name";
description
"This list describes a collection of local
logging files.";
leaf name {
type inet:uri {
pattern 'file:.*';
}
description
"This leaf specifies the name of the log
file, which MUST use the uri scheme
file:.";
reference
"RFC 8089: The file URI Scheme";
}
uses selector;
uses structured-data;
container file-rotation {
description
"This container describes the configuration
parameters for log file rotation.";
leaf number-of-files {
if-feature "file-limit-size";
type uint32;
default "1";
description
"This leaf specifies the maximum number
of log files retained. Specify 1 for
implementations that only support one
log file.";
}
leaf max-file-size {
if-feature "file-limit-size";
type uint32;
units "megabytes";
description
"This leaf specifies the maximum log
file size.";
}
leaf rollover {
if-feature "file-limit-duration";
type uint32;
units "minutes";
description
"This leaf specifies the length of time
that log events should be written to a
specific log file. Log events that
arrive after the rollover period cause
the current log file to be closed and
a new log file to be opened.";
}
leaf retention {
if-feature "file-limit-duration";
type uint32;
units "minutes";
description
"This leaf specifies the length of time
that completed/closed log event files
should be stored in the file system
before they are removed.";
}
}
}
}
container remote {
if-feature "remote-action";
description
"This container describes the configuration
parameters for forwarding syslog messages
to remote relays or collectors.";
list destination {
key "name";
description
"This list describes a collection of remote logging
destinations.";
leaf name {
type string;
description
"An arbitrary name for the endpoint to connect to.";
}
choice transport {
mandatory true;
description
"This choice describes the transport option.";
case udp {
container udp {
description
"This container describes the UDP transport
options.";
reference
"RFC 5426: Transmission of Syslog Messages over
UDP";
list udp {
key "address";
description
"List of all UDP sessions.";
leaf address {
type inet:host;
description
"The leaf uniquely specifies the address of the
remote host. One of the following must be
specified:
- an ipv4 address,
- an ipv6 address, or a
- host name.";
}
leaf port {
type inet:port-number;
default "514";
description
"This leaf specifies the port number used to
deliver messages to the remote server.";
}
}
}
}
case tls {
container tls {
description
"This container describes the TLS transport
options.";
reference
"RFC 5425: Transport Layer Security (TLS) Transport
Mapping for Syslog ";
list tls {
key "address";
description
"List of all TLS-based sessions.";
leaf address {
type inet:host;
description
"The leaf uniquely specifies the address of the
remote host. One of the following must be
specified: an ipv4 address, an ipv6 address,
or a host name.";
}
leaf port {
type inet:port-number;
default "6514";
description
"TCP port 6514 has been allocated as the
default port for syslog over TLS.";
}
uses tlsc:tls-client-grouping;
}
}
}
}
uses selector;
uses structured-data;
leaf facility-override {
type identityref {
base syslog-facility;
}
description
"If specified, this leaf specifies the facility used
to override the facility in messages delivered to the
remote server.";
}
leaf source-interface {
if-feature "remote-source-interface";
type if:interface-ref;
description
"This leaf sets the source interface to be used to
send messages to the remote syslog server. If not set,
messages can be sent on any interface.";
}
container signing {
if-feature "signed-messages";
presence "If present, syslog-signing options is
activated.";
description
"This container describes the configuration
parameters for signed syslog messages.";
reference
"RFC 5848: Signed Syslog Messages";
container cert-signers {
description
"This container describes the signing certificate
configuration for Signature Group 0, which covers
the case for administrators who want all Signature
Blocks to be sent to a single destination.";
list cert-signer {
key "name";
description
"This list describes a collection of syslog message
signers.";
leaf name {
type string;
description
"This leaf specifies the name of the syslog
message signer.";
}
container cert {
uses ct:asymmetric-key-pair-with-cert-grouping;
description
"This is the certificate that is periodically
sent to the remote receiver. The certificate is
inherently associated with its private
and public keys.";
}
leaf hash-algorithm {
type enumeration {
enum SHA1 {
value 1;
description
"This enum describes the SHA1 algorithm.";
}
enum SHA256 {
value 2;
description
"This enum describes the SHA256 algorithm.";
}
}
description
"This leaf describes the syslog signer hash
algorithm used.";
}
}
leaf cert-initial-repeat {
type uint32;
default "3";
description
"This leaf specifies the number of times each
Certificate Block should be sent before the first
message is sent.";
}
leaf cert-resend-delay {
type uint32;
units "seconds";
default "3600";
description
"This leaf specifies the maximum time delay in
seconds until resending the Certificate Block.";
}
leaf cert-resend-count {
type uint32;
default "0";
description
"This leaf specifies the maximum number of other
syslog messages to send until resending the
Certificate Block.";
}
leaf sig-max-delay {
type uint32;
units "seconds";
default "60";
description
"This leaf specifies when to generate a new
Signature Block. If this many seconds have elapsed
since the message with the first message number
of the Signature Block was sent, a new Signature
Block should be generated.";
}
leaf sig-number-resends {
type uint32;
default "0";
description
"This leaf specifies the number of times a
Signature Block is resent. (It is recommended to
select a value of greater than 0 in particular
when the UDP transport as in RFC 5426 is used.)";
}
leaf sig-resend-delay {
type uint32;
units "seconds";
default "5";
description
"This leaf specifies when to send the next
Signature Block transmission based on time. If
this many seconds have elapsed since the previous
sending of this Signature Block, resend it.";
}
leaf sig-resend-count {
type uint32;
default "0";
description
"This leaf specifies when to send the next
Signature Block transmission based on a count.
If this many other syslog messages have been sent
since the previous sending of this Signature
Block, resend it. A value of 0 means that you
don't resend based on the number of messages.";
}
}
}
}
}
}
}
}
Usage ExamplesThe following examples are in XML .Syslog Configuration for Severity CriticalThis example shows how the console logging of syslog of severity critical can be enabled.Syslog Configuration for Severity Critical
<?xml version="1.0" encoding="UTF-8"?>
<syslog xmlns="urn:ietf:params:xml:ns:yang:ietf-syslog">
<actions>
<console>
<filter>
<facility-list>
<facility>all</facility>
<severity>critical</severity>
</facility-list>
</filter>
</console>
</actions>
</syslog>Remote Syslog ConfigurationThis example shows how the remote logging of syslogs to UDP destination
foo.example.com for facility auth and severity error can be enabled.Remote Syslog Configuration
<?xml version="1.0" encoding="UTF-8"?>
<syslog xmlns="urn:ietf:params:xml:ns:yang:ietf-syslog">
<actions>
<remote>
<destination>
<name>remote1</name>
<udp>
<udp>
<address>foo.example.com</address>
</udp>
</udp>
<filter>
<facility-list>
<facility>auth</facility>
<severity>error</severity>
</facility-list>
</filter>
</destination>
</remote>
</actions>
</syslog>IANA ConsiderationsThe IETF XML RegistryThis document registers one URI in the "IETF XML Registry", following the format defined in :
URI:
urn:ietf:params:xml:ns:yang:ietf-syslog
Registrant Contact:
The IESG.
XML:
N/A; the requested URI is an XML namespace.
The YANG Module Names RegistryThis document registers one YANG module in the "YANG Module Names"
registry , following the format in :
Name:
ietf-syslog
Namespace:
urn:ietf:params:xml:ns:yang:ietf-syslog
Prefix:
syslog
Reference:
RFC 9742
Security Considerations
This section is modeled after the template defined in .
The "ietf-syslog" YANG module defines a data model that is designed to be
accessed via YANG-based management protocols, such as NETCONF and RESTCONF . These protocols
have to use a secure transport layer (e.g., SSH ,
TLS , and QUIC ) and have
to use mutual authentication.
The Network Configuration Access Control Model (NACM) provides the means to restrict access for particular
NETCONF or RESTCONF users to a preconfigured subset of all available
NETCONF or RESTCONF protocol operations and content.
This module imports groupings from ietf-crypto-types YANG module
defined in YANG
Groupings for Crypto Types. Security considerations
described in that document apply to this module also.
There are a number of data nodes defined in this YANG module that are
writable/creatable/deletable (i.e., "config true", which is the default).
All writable data nodes are likely to be reasonably sensitive or vulnerable
in some network environments. Write operations (e.g., edit-config) and
delete operations to these data nodes without proper protection or
authentication can have a negative effect on network operations. The
following subtrees and data nodes have particular
sensitivities/vulnerabilities:
facility-filter/pattern-match:
When writing
this node, implementations MUST ensure that the regular
expression pattern match is not constructed to cause a regular
expression denial-of-service attack due to a pattern that
causes the regular expression implementation to work very
slowly (exponentially related to input size).
remote/destination/signing/cert-signer:
When writing this subtree, implementations MUST NOT
specify a private key that is used for any other purpose.
Some of the readable data nodes in this YANG module may be considered
sensitive or vulnerable in some network environments. It is thus important
to control read access (e.g., via get, get-config, or notification) to
these data nodes. Specifically, the following subtrees and data nodes have
particular sensitivities/ vulnerabilities:
remote/destination/transport:
This subtree
contains information about other hosts in the network, the
services available on those hosts, and the TLS transport
certificate properties if TLS is selected as the transport
protocol. Knowing that a service like syslog (udp/514) is
enabled on the host will allow a malicious user to spam the
host on that port.
remote/destination/signing:
This subtree contains
information about the syslog message signing properties,
including signing certificate information.
There are no particularly sensitive RPC or action operations.
ReferencesNormative ReferencesKey words for use in RFCs to Indicate Requirement LevelsIn many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.The IETF XML RegistryThis document describes an IANA maintained registry for IETF standards which use Extensible Markup Language (XML) related items such as Namespaces, Document Type Declarations (DTDs), Schemas, and Resource Description Framework (RDF) Schemas.The Syslog ProtocolThis document describes the syslog protocol, which is used to convey event notification messages. This protocol utilizes a layered architecture, which allows the use of any number of transport protocols for transmission of syslog messages. It also provides a message format that allows vendor-specific extensions to be provided in a structured way.This document has been written with the original design goals for traditional syslog in mind. The need for a new layered specification has arisen because standardization efforts for reliable and secure syslog extensions suffer from the lack of a Standards-Track and transport-independent RFC. Without this document, each other standard needs to define its own syslog packet format and transport mechanism, which over time will introduce subtle compatibility issues. This document tries to provide a foundation that syslog extensions can build on. This layered architecture approach also provides a solid basis that allows code to be written once for each syslog feature rather than once for each transport. [STANDARDS-TRACK]Transport Layer Security (TLS) Transport Mapping for SyslogThis document describes the use of Transport Layer Security (TLS) to provide a secure connection for the transport of syslog messages. This document describes the security threats to syslog and how TLS can be used to counter such threats.Transmission of Syslog Messages over UDPThis document describes the transport for syslog messages over UDP/ IPv4 or UDP/IPv6. The syslog protocol layered architecture provides for support of any number of transport mappings. However, for interoperability purposes, syslog protocol implementers are required to support this transport mapping. [STANDARDS-TRACK]Signed Syslog MessagesThis document describes a mechanism to add origin authentication, message integrity, replay resistance, message sequencing, and detection of missing messages to the transmitted syslog messages. This specification is intended to be used in conjunction with the work defined in RFC 5424, "The Syslog Protocol". [STANDARDS-TRACK]Common YANG Data TypesThis document introduces a collection of common data types to be used with the YANG data modeling language. This document obsoletes RFC 6021.The YANG 1.1 Data Modeling LanguageYANG is a data modeling language used to model configuration data, state data, Remote Procedure Calls, and notifications for network management protocols. This document describes the syntax and semantics of version 1.1 of the YANG language. YANG version 1.1 is a maintenance release of the YANG language, addressing ambiguities and defects in the original specification. There are a small number of backward incompatibilities from YANG version 1. This document also specifies the YANG mappings to the Network Configuration Protocol (NETCONF).The "file" URI SchemeThis document provides a more complete specification of the "file" Uniform Resource Identifier (URI) scheme and replaces the very brief definition in Section 3.10 of RFC 1738.It defines a common syntax that is intended to interoperate across the broad spectrum of existing usages. At the same time, it notes some other current practices around the use of file URIs.Ambiguity of Uppercase vs Lowercase in RFC 2119 Key WordsRFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings.Network Configuration Access Control ModelThe standardization of network configuration interfaces for use with the Network Configuration Protocol (NETCONF) or the RESTCONF protocol requires a structured and secure operating environment that promotes human usability and multi-vendor interoperability. There is a need for standard mechanisms to restrict NETCONF or RESTCONF protocol access for particular users to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and content. This document defines such an access control model.This document obsoletes RFC 6536.A YANG Data Model for Interface ManagementThis document defines a YANG data model for the management of network interfaces. It is expected that interface-type-specific data models augment the generic interfaces data model defined in this document. The data model includes definitions for configuration and system state (status information and counters for the collection of statistics).The YANG data model in this document conforms to the Network Management Datastore Architecture (NMDA) defined in RFC 8342.This document obsoletes RFC 7223.YANG LibraryThis document describes a YANG library that provides information about the YANG modules, datastores, and datastore schemas used by a network management server. Simple caching mechanisms are provided to allow clients to minimize retrieval of this information. This version of the YANG library supports the Network Management Datastore Architecture (NMDA) by listing all datastores supported by a network management server and the schema that is used by each of these datastores.YANG Data Types and Groupings for CryptographyThis document presents a YANG 1.1 (RFC 7950) module defining identities, typedefs, and groupings useful to cryptographic applications.YANG Groupings for TLS Clients and TLS ServersThis document presents four YANG 1.1 modules -- three IETF modules and one supporting IANA module.The three IETF modules are "ietf-tls-common", "ietf-tls-client", and "ietf-tls-server". The "ietf-tls-client" and "ietf-tls-server" modules are the primary productions of this work, supporting the configuration and monitoring of TLS clients and servers.The IANA module is "iana-tls-cipher-suite-algs". This module defines YANG enumerations that provide support for an IANA-maintained algorithm registry."Chapter 9: Regular Expressions" The Open Group Base Specifications Issue 8, IEEE Std 1003.1-2024The Open GroupExtensible Markup Language (XML) 1.0 (Fifth Edition)Informative ReferencesThe Secure Shell (SSH) Authentication ProtocolThe Secure Shell Protocol (SSH) is a protocol for secure remote login and other secure network services over an insecure network. This document describes the SSH authentication protocol framework and public key, password, and host-based client authentication methods. Additional authentication methods are described in separate documents. The SSH authentication protocol runs on top of the SSH transport layer protocol and provides a single authenticated tunnel for the SSH connection protocol. [STANDARDS-TRACK]Network Configuration Protocol (NETCONF)The Network Configuration Protocol (NETCONF) defined in this document provides mechanisms to install, manipulate, and delete the configuration of network devices. It uses an Extensible Markup Language (XML)-based data encoding for the configuration data as well as the protocol messages. The NETCONF protocol operations are realized as remote procedure calls (RPCs). This document obsoletes RFC 4741. [STANDARDS-TRACK]RESTCONF ProtocolThis document describes an HTTP-based protocol that provides a programmatic interface for accessing data defined in YANG, using the datastore concepts defined in the Network Configuration Protocol (NETCONF).YANG Tree DiagramsThis document captures the current syntax used in YANG module tree diagrams. The purpose of this document is to provide a single location for this definition. This syntax may be updated from time to time based on the evolution of the YANG language.Network Management Datastore Architecture (NMDA)Datastores are a fundamental concept binding the data models written in the YANG data modeling language to network management protocols such as the Network Configuration Protocol (NETCONF) and RESTCONF. This document defines an architectural framework for datastores based on the experience gained with the initial simpler model, addressing requirements that were not well supported in the initial model. This document updates RFC 7950.The Transport Layer Security (TLS) Protocol Version 1.3This document specifies version 1.3 of the Transport Layer Security (TLS) protocol. TLS allows client/server applications to communicate over the Internet in a way that is designed to prevent eavesdropping, tampering, and message forgery.This document updates RFCs 5705 and 6066, and obsoletes RFCs 5077, 5246, and 6961. This document also specifies new requirements for TLS 1.2 implementations.QUIC: A UDP-Based Multiplexed and Secure TransportThis document defines the core of the QUIC transport protocol. QUIC provides applications with flow-controlled streams for structured communication, low-latency connection establishment, and network path migration. QUIC includes security measures that ensure confidentiality, integrity, and availability in a range of deployment circumstances. Accompanying documents describe the integration of TLS for key negotiation, loss detection, and an exemplary congestion control algorithm.Guidelines for Authors and Reviewers of Documents Containing YANG Data ModelsYumaWorksOrangeHuaweiThis memo provides guidelines for authors and reviewers of specifications containing YANG modules, including IANA-maintained modules. Recommendations and procedures are defined, which are intended to increase interoperability and usability of Network Configuration Protocol (NETCONF) and RESTCONF Protocol implementations that utilize YANG modules. This document obsoletes RFC 8407. Also, this document updates RFC 8126 by providing additional guidelines for writing the IANA considerations for RFCs that specify IANA-maintained modules.Work in ProgressTree DiagramsComplete Tree Diagram
[note: '\' line wrapping for formatting only]
module: ietf-syslog
+--rw syslog!
+--rw actions
+--rw console! {console-action}?
| +--rw filter
| | +--rw facility-list* [facility severity]
| | +--rw facility union
| | +--rw severity union
| | +--rw advanced-compare {select-adv-compare}?
| | +--rw compare? enumeration
| | +--rw action? identityref
| +--rw pattern-match? string {select-match}?
+--rw file {file-action}?
| +--rw log-file* [name]
| +--rw name inet:uri
| +--rw filter
| | +--rw facility-list* [facility severity]
| | +--rw facility union
| | +--rw severity union
| | +--rw advanced-compare {select-adv-compare}?
| | +--rw compare? enumeration
| | +--rw action? identityref
| +--rw pattern-match? string {select-match}?
| +--rw structured-data? boolean {structured-data}?
| +--rw file-rotation
| +--rw number-of-files? uint32 {file-limit-size}?
| +--rw max-file-size? uint32 {file-limit-size}?
| +--rw rollover? uint32
| | {file-limit-duration}?
| +--rw retention? uint32
| {file-limit-duration}?
+--rw remote {remote-action}?
+--rw destination* [name]
+--rw name string
+--rw (transport)
| +--:(udp)
| | +--rw udp
| | +--rw udp* [address]
| | +--rw address inet:host
| | +--rw port? inet:port-number
| +--:(tls)
| +--rw tls
| +--rw tls* [address]
| +--rw address inet:host
| +--rw port?
| | inet:port-number
| +--rw client-identity!
| | +--rw (auth-type)
| | +--:(certificate)
| | | {client-ident-x509-cert}?
| | | +--rw certificate
| | | +--rw (inline-or-keystore)
| | | +--:(inline)
| | | | {inline-definition\
s-supported}?
| | | | +--rw inline-definition
| | | | +--rw public-key-form\
at?
| | | | | identityref
| | | | +--rw public-key?
| | | | | binary
| | | | +--rw private-key-for\
mat?
| | | | | identityref
| | | | +--rw (private-key-ty\
pe)
| | | | | +--:(cleartext-pri\
vate-key)
| | | | | | {cleartex\
t-private-keys}?
| | | | | | +--rw cleartext\
-private-key?
| | | | | | binary
| | | | | +--:(hidden-privat\
e-key)
| | | | | | {hidden-p\
rivate-keys}?
| | | | | | +--rw hidden-pr\
ivate-key?
| | | | | | empty
| | | | | +--:(encrypted-pri\
vate-key)
| | | | | {encrypte\
d-private-keys}?
| | | | | +--rw encrypted\
-private-key
| | | | | +--rw encryp\
ted-by
| | | | | +--rw encryp\
ted-value-format
| | | | | | iden\
tityref
| | | | | +--rw encryp\
ted-value
| | | | | bina\
ry
| | | | +--rw cert-data?
| | | | | end-entity-ce\
rt-cms
| | | | +---n certificate-exp\
iration
| | | | | {certificate-\
expiration-notification}?
| | | | | +-- expiration-dat\
e
| | | | | yang:date-\
and-time
| | | | +---x generate-csr
| | | | {csr-generati\
on}?
| | | | +---w input
| | | | | +---w csr-forma\
t
| | | | | | identit\
yref
| | | | | +---w csr-info
| | | | | csr-inf\
o
| | | | +--ro output
| | | | +--ro (csr-type\
)
| | | | +--:(p10-csr\
)
| | | | +--ro p10\
-csr?
| | | | p\
10-csr
| | | +--:(central-keystore)
| | | {central-keystore-\
supported,asymmetric-keys}?
| | | +--rw central-keystore-r\
eference
| | | +--rw asymmetric-key?\
| | | | ks:central-as\
ymmetric-key-ref
| | | | {central-keys\
tore-supported,asymmetric-keys}?
| | | +--rw certificate?
| | | leafref
| | +--:(raw-public-key)
| | | {client-ident-raw-public-ke\
y}?
| | | +--rw raw-private-key
| | | +--rw (inline-or-keystore)
| | | +--:(inline)
| | | | {inline-definition\
s-supported}?
| | | | +--rw inline-definition
| | | | +--rw public-key-form\
at?
| | | | | identityref
| | | | +--rw public-key?
| | | | | binary
| | | | +--rw private-key-for\
mat?
| | | | | identityref
| | | | +--rw (private-key-ty\
pe)
| | | | +--:(cleartext-pri\
vate-key)
| | | | | {cleartex\
t-private-keys}?
| | | | | +--rw cleartext\
-private-key?
| | | | | binary
| | | | +--:(hidden-privat\
e-key)
| | | | | {hidden-p\
rivate-keys}?
| | | | | +--rw hidden-pr\
ivate-key?
| | | | | empty
| | | | +--:(encrypted-pri\
vate-key)
| | | | {encrypte\
d-private-keys}?
| | | | +--rw encrypted\
-private-key
| | | | +--rw encryp\
ted-by
| | | | +--rw encryp\
ted-value-format
| | | | | iden\
tityref
| | | | +--rw encryp\
ted-value
| | | | bina\
ry
| | | +--:(central-keystore)
| | | {central-keystore-\
supported,asymmetric-keys}?
| | | +--rw central-keystore-r\
eference?
| | | ks:central-asymm\
etric-key-ref
| | +--:(tls12-psk)
| | | {client-ident-tls12-psk}?
| | | +--rw tls12-psk
| | | +--rw (inline-or-keystore)
| | | | +--:(inline)
| | | | | {inline-definition\
s-supported}?
| | | | | +--rw inline-definition
| | | | | +--rw key-format?
| | | | | | identityref
| | | | | +--rw (key-type)
| | | | | +--:(cleartext-sym\
metric-key)
| | | | | | +--rw cleartext\
-symmetric-key?
| | | | | | binary
| | | | | | {cleart\
ext-symmetric-keys}?
| | | | | +--:(hidden-symmet\
ric-key)
| | | | | | {hidden-s\
ymmetric-keys}?
| | | | | | +--rw hidden-sy\
mmetric-key?
| | | | | | empty
| | | | | +--:(encrypted-sym\
metric-key)
| | | | | {encrypte\
d-symmetric-keys}?
| | | | | +--rw encrypted\
-symmetric-key
| | | | | +--rw encryp\
ted-by
| | | | | +--rw encryp\
ted-value-format
| | | | | | iden\
tityref
| | | | | +--rw encryp\
ted-value
| | | | | bina\
ry
| | | | +--:(central-keystore)
| | | | {central-keystore-\
supported,symmetric-keys}?
| | | | +--rw central-keystore-r\
eference?
| | | | ks:central-symme\
tric-key-ref
| | | +--rw id?
| | | string
| | +--:(tls13-epsk)
| | {client-ident-tls13-epsk}?
| | +--rw tls13-epsk
| | +--rw (inline-or-keystore)
| | | +--:(inline)
| | | | {inline-definition\
s-supported}?
| | | | +--rw inline-definition
| | | | +--rw key-format?
| | | | | identityref
| | | | +--rw (key-type)
| | | | +--:(cleartext-sym\
metric-key)
| | | | | +--rw cleartext\
-symmetric-key?
| | | | | binary
| | | | | {cleart\
ext-symmetric-keys}?
| | | | +--:(hidden-symmet\
ric-key)
| | | | | {hidden-s\
ymmetric-keys}?
| | | | | +--rw hidden-sy\
mmetric-key?
| | | | | empty
| | | | +--:(encrypted-sym\
metric-key)
| | | | {encrypte\
d-symmetric-keys}?
| | | | +--rw encrypted\
-symmetric-key
| | | | +--rw encryp\
ted-by
| | | | +--rw encryp\
ted-value-format
| | | | | iden\
tityref
| | | | +--rw encryp\
ted-value
| | | | bina\
ry
| | | +--:(central-keystore)
| | | {central-keystore-\
supported,symmetric-keys}?
| | | +--rw central-keystore-r\
eference?
| | | ks:central-symme\
tric-key-ref
| | +--rw external-identity
| | | string
| | +--rw hash?
| | | tlscmn:epsk-supported-\
hash
| | +--rw context?
| | | string
| | +--rw target-protocol?
| | | uint16
| | +--rw target-kdf?
| | uint16
| +--rw server-authentication
| | +--rw ca-certs! {server-auth-x509-cert}\
?
| | | +--rw (inline-or-truststore)
| | | +--:(inline)
| | | | {inline-definitions-supp\
orted}?
| | | | +--rw inline-definition
| | | | +--rw certificate* [name]
| | | | +--rw name
| | | | | string
| | | | +--rw cert-data
| | | | | trust-anchor-cer\
t-cms
| | | | +---n certificate-expira\
tion
| | | | {certificate-exp\
iration-notification}?
| | | | +-- expiration-date
| | | | yang:date-and\
-time
| | | +--:(central-truststore)
| | | {central-truststore-supp\
orted,certificates}?
| | | +--rw central-truststore-refer\
ence?
| | | ts:central-certificate\
-bag-ref
| | +--rw ee-certs! {server-auth-x509-cert}\
?
| | | +--rw (inline-or-truststore)
| | | +--:(inline)
| | | | {inline-definitions-supp\
orted}?
| | | | +--rw inline-definition
| | | | +--rw certificate* [name]
| | | | +--rw name
| | | | | string
| | | | +--rw cert-data
| | | | | trust-anchor-cer\
t-cms
| | | | +---n certificate-expira\
tion
| | | | {certificate-exp\
iration-notification}?
| | | | +-- expiration-date
| | | | yang:date-and\
-time
| | | +--:(central-truststore)
| | | {central-truststore-supp\
orted,certificates}?
| | | +--rw central-truststore-refer\
ence?
| | | ts:central-certificate\
-bag-ref
| | +--rw raw-public-keys!
| | | {server-auth-raw-public-key}?
| | | +--rw (inline-or-truststore)
| | | +--:(inline)
| | | | {inline-definitions-supp\
orted}?
| | | | +--rw inline-definition
| | | | +--rw public-key* [name]
| | | | +--rw name
| | | | | string
| | | | +--rw public-key-format
| | | | | identityref
| | | | +--rw public-key
| | | | binary
| | | +--:(central-truststore)
| | | {central-truststore-supp\
orted,public-keys}?
| | | +--rw central-truststore-refer\
ence?
| | | ts:central-public-key-\
bag-ref
| | +--rw tls12-psks? empty
| | | {server-auth-tls12-psk}?
| | +--rw tls13-epsks? empty
| | {server-auth-tls13-epsk}?
| +--rw hello-params {tlscmn:hello-params}?
| | +--rw tls-versions
| | | +--rw min? identityref
| | | +--rw max? identityref
| | +--rw cipher-suites
| | +--rw cipher-suite*
| | tlscsa:tls-cipher-suite-algo\
rithm
| +--rw keepalives {tls-client-keepalives}?
| +--rw peer-allowed-to-send? empty
| +--rw test-peer-aliveness!
| +--rw max-wait? uint16
| +--rw max-attempts? uint8
+--rw filter
| +--rw facility-list* [facility severity]
| +--rw facility union
| +--rw severity union
| +--rw advanced-compare {select-adv-compare}?
| +--rw compare? enumeration
| +--rw action? identityref
+--rw pattern-match? string {select-match}?
+--rw structured-data? boolean {structured-data}?
+--rw facility-override? identityref
+--rw source-interface? if:interface-ref
| {remote-source-interface}?
+--rw signing! {signed-messages}?
+--rw cert-signers
+--rw cert-signer* [name]
| +--rw name string
| +--rw cert
| | +--rw public-key-format?
| | | identityref
| | +--rw public-key? binar\
y
| | +--rw private-key-format?
| | | identityref
| | +--rw (private-key-type)
| | | +--:(cleartext-private-key)
| | | | {cleartext-private-keys}?
| | | | +--rw cleartext-private-key? binar\
y
| | | +--:(hidden-private-key)
| | | | {hidden-private-keys}?
| | | | +--rw hidden-private-key? empty\
| | | +--:(encrypted-private-key)
| | | {encrypted-private-keys}?
| | | +--rw encrypted-private-key
| | | +--rw encrypted-by
| | | +--rw encrypted-value-format
| | | | identityref
| | | +--rw encrypted-value
| | | binary
| | +--rw cert-data?
| | | end-entity-cert-cms
| | +---n certificate-expiration
| | | {certificate-expiration-notificati\
on}?
| | | +-- expiration-date
| | | yang:date-and-time
| | +---x generate-csr {csr-generation}?
| | +---w input
| | | +---w csr-format identityref
| | | +---w csr-info csr-info
| | +--ro output
| | +--ro (csr-type)
| | +--:(p10-csr)
| | +--ro p10-csr? p10-csr
| +--rw hash-algorithm? enumeration
+--rw cert-initial-repeat? uint32
+--rw cert-resend-delay? uint32
+--rw cert-resend-count? uint32
+--rw sig-max-delay? uint32
+--rw sig-number-resends? uint32
+--rw sig-resend-delay? uint32
+--rw sig-resend-count? uint32
Implementer GuidelinesExtending FacilitiesMany vendors extend the list of facilities available for logging in
their implementation. Additional facilities may not work with the
syslog protocol as defined in . Thus, such facilities
apply for local syslog-like logging functionality.The following is an example that shows how additional facilities
could be added to the list of available facilities (two facilities are added in this example):
module example-vendor-syslog-types {
namespace "http://example.com/ns/vendor-syslog-types";
prefix vendor-syslogtypes;
import ietf-syslog {
prefix syslog;
}
organization
"Example, Inc.";
contact
"Example, Inc.
Customer Service
Email: syslog-yang@example.com";
description
"This module contains a collection of vendor-specific YANG type
definitions for Syslog.";
revision 2025-04-30 {
description
"Version 1.0";
reference
"Vendor Syslog Types: Syslog YANG Module";
}
identity vendor_specific_type_1 {
base syslog:syslog-facility;
description
"Adding vendor-specific type 1 to syslog-facility";
}
identity vendor_specific_type_2 {
base syslog:syslog-facility;
description
"Adding vendor-specific type 2 to syslog-facility";
}
}Syslog Terminal OutputTerminal output with requirements more complex than the console
subtree currently provides are expected to be supported via vendor
extensions rather than handled via the file subtree.Syslog File Naming ConventionThe syslog/file/log-file/file-rotation container contains
configuration parameters for syslog file rotation. This section
describes how these fields might be used by an implementer to name
syslog files in a rotation process. This information is offered as
an informative guide only.When an active syslog file with a name specified by log-file/name
reaches log-file/max-file-size and/or syslog events arrive after the
period specified by log-file/rollover, the logging system can close
the file, compress it, and name the archive file <log-file/
name>.0.gz. The logging system can then open a new active syslog
file <log-file/name>.When the new syslog file reaches either of the size limits referenced
above, <log-file/name>.0.gz can be renamed <log-file/name>.1.gz and
the new syslog file can be closed, compressed, and renamed <log-file/
name>.0.gz. Each time that a new syslog file is closed, each of the
prior syslog archive files named <log-file/name>.<n>.gz can be
renamed to <log-file/name>.<n + 1>.gz.Removal of archive log files could occur when either or both:
log-file/number-of-files is specified. The logging system can create
up to log-file/number-of-files syslog archive files, after which the
contents of the oldest archived file could be overwritten.
log-file/retention is specified. The logging system can remove those
syslog archive files whose file expiration time (file creation time
plus the specified log-file/retention time) is prior to the current
time.
AcknowledgementsThe authors wish to thank the following who commented on this
proposal:, , , , , , , , , , , , ,
, , , , ,
, ,
, , , , , , , , and .Authors' AddressesCiscoUnited States of Americajclarke@cisco.comKloud ServicesUnited States of Americamjethanandani@gmail.comCisco Systems Inc.170 West Tasman DriveSan JoseCA95134United States of America+1 415 819-6111clyde@clydewildes.comVerizon Wireless500 W Dove Rd.SouthlakeTX76092United States of America+1 512 650-0210kirankoushik.agraharasreenivasa@verizonwireless.com