NETMOD WG C. Wildes, Ed.
Internet-Draft K. Koushik, Ed.
Intended status: Standards Track Cisco Systems Inc.
Expires: November 11, 2016 May 10, 2016
SYSLOG YANG Model
draft-ietf-netmod-syslog-model-08
Abstract
This document describes a data model for the Syslog protocol which is
used to convey event notification messages.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on November 11, 2016.
Copyright Notice
Copyright (c) 2016 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
(http://trustee.ietf.org/license-info) 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 Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 3
3. Design of the SYSLOG Model . . . . . . . . . . . . . . . . . 3
3.1. SYSLOG Module . . . . . . . . . . . . . . . . . . . . . . 5
4. SYSLOG YANG Models . . . . . . . . . . . . . . . . . . . . . 9
4.1. SYSLOG-TYPES Module . . . . . . . . . . . . . . . . . . . 9
4.2. Syslog Module . . . . . . . . . . . . . . . . . . . . . . 14
4.3. A Syslog Example . . . . . . . . . . . . . . . . . . . . 29
5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 30
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 31
7. Security Considerations . . . . . . . . . . . . . . . . . . . 31
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 32
8.1. Normative References . . . . . . . . . . . . . . . . . . 32
8.2. Informative References . . . . . . . . . . . . . . . . . 33
Appendix A. Implementor Guidelines . . . . . . . . . . . . . . . 33
A.1. Extending Facilities . . . . . . . . . . . . . . . . . . 33
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 34
1. Introduction
Operating systems, processes and applications generate messages
indicating their own status or the occurrence of events. These
messages are useful for managing and/or debugging the network and its
services. The BSD Syslog protocol is a widely adopted protocol that
is used for transmission and processing of the messages.
Since each process, application and operating system was written
somewhat independently, there is little uniformity to the content of
Syslog messages. For this reason, no assumption is made upon the
formatting or contents of the messages. The protocol is simply
designed to transport these event messages. No acknowledgement of
the receipt is made.
Essentially, a Syslog process receives messages (from the kernel,
processes, applications or other Syslog processes) and processes
those. The processing involves logging to a local file, displaying
on console, user terminal, and/or relaying to syslog processes on
other machines. The processing is determined by the "facility" that
originated the message and the "severity" assigned to the message by
the facility.
We are using definitions of Syslog protocol from [RFC5424] in this
RFC.
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1.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
2. Problem Statement
This document defines a YANG [RFC6020] configuration data model that
may be used to monitor and control one or more syslog processes
running on a system. YANG models can be used with network management
agents such as NETCONF [RFC6241] to install, manipulate, and delete
the configuration of network devices.
This module makes use of the YANG "feature" construct which allows
implementations to support only those Syslog features that lie within
their capabilities.
This module can be used to configure the SYSLOG application
conceptual layer [RFC5424].
3. Design of the SYSLOG Model
The syslog model was designed by comparing various syslog features
implemented by various vendors' in different implementations.
This draft addresses the common leafs between implementations and
creates a common model, which can be augmented with proprietary
features, if necessary. The base model is designed to be very simple
for maximum flexibility.
Syslog consists of message originators, and message distributors.
The following digram shows syslog messages flowing from a message
originator, to message distributors where suppression filtering can
take place.
Many vendors extend the list of facilities available for logging in
their implementation. An example is included in Extending Facilities
(Appendix A.1).
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Message Originators
+-------------+ +-------------+ +-------------+ +-------------+
| Various | | OS | | | | Remote |
| Components | | Kernel | | Line Cards | | Servers |
+-------------+ +-------------+ +-------------+ +-------------+
+-------------+ +-------------+ +-------------+ +-------------+
| SNMP | | Interface | | Standby | | Syslog |
| Events | | Events | | Supervisor | | Itself |
+-------------+ +-------------+ +-------------+ +-------------+
| |
+----------------------------------------------------------------+
|
|
|
|
+-----------+------------+--------------+
| | | |
v v v |
Message Distributors |
+----------+ +----------+ +----------+ |
| | | Log | | Log | |
| Console | | Buffer | | File(s) | |
+----------+ +----------+ +----------+ |
|
+-------------+-------------+
| | |
v v v
+----------------+ +-----------+ +-----------+
|Remote Relay(s)/| | | |User |
|Collectors(s) | |Terminal(s)| |Sessions(s)|
+----------------+ +-----------+ +-----------+
The leaves in the base syslog model log-input-transports container
correspond to remote message originators or remote message relays.
The leaves in the base syslog model log-actions container correspond
to each message distributor:
console
log buffer
log file(s)
remote relay(s)/collector(s)
terminal(s)
user session(s).
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Optional features are used to specified functionality that is present
in specific vendor configurations.
3.1. SYSLOG Module
A simplified graphical representation of the complete data tree is
presented here.
Each node is printed as:
<status> <flags> <name> <opts> <type> <if-features>
<status> is one of:
+ for current
x for deprecated
o for obsolete
<flags> is one of:
rw for configuration data
ro for non-configuration data
-x for rpcs
-n for notifications
<name> is the name of the node
(<name>) means that the node is a choice node
:(<name>) means that the node is a case node
If the node is augmented into the tree from another module, its name
is printed as <prefix>:<name>.
<opts> is one of:
? for an optional leaf or choice
! for a presence container
* for a leaf-list or list
[<keys>] for a list's keys
<type> is the name of the type for leafs and leaf-lists
If the type is a leafref, the type is printed as "-> TARGET", where
TARGET is either the leafref path, with prefixed removed if possible.
<if-features> is the list of features this node depends on, printed
within curly brackets and a question mark "{...}?"
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module: ietf-syslog
+--rw syslog
+--rw log-input-transports {syslog-relay}?
| +--rw receiver* [name]
| +--rw name string
| +--rw (transport)
| | +--:(tcp)
| | | +--rw tcp
| | | +--rw address? inet:host
| | | +--rw port? inet:port-number
| | +--:(udp)
| | | +--rw udp
| | | +--rw address? inet:host
| | | +--rw port? inet:port-number
| | +--:(tls)
| | +--rw tls
| | +--rw address? inet:host
| | +--rw port? inet:port-number
| +--rw structured-data? boolean {structured-data}?
| +--rw syslog-sign! {signed-messages}?
+--rw log-actions
+--rw console!
| +--rw log-selector
| +--rw (selector-facility)
| | +--:(no-log-facility)
| | | +--rw no-facilities? empty
| | +--:(log-facility)
| | +--rw log-facility* [facility]
| | +--rw facility union
| | +--rw severity union
| | +--rw compare-op? enumeration {select-sev-compare}?
| +--rw pattern-match? string {select-match}?
+--rw buffer
| +--rw log-selector
| | +--rw (selector-facility)
| | | +--:(no-log-facility)
| | | | +--rw no-facilities? empty
| | | +--:(log-facility)
| | | +--rw log-facility* [facility]
| | | +--rw facility union
| | | +--rw severity union
| | | +--rw compare-op? enumeration {select-sev-compare}?
| | +--rw pattern-match? string {select-match}?
| +--rw buffer-size-bytes? uint64 {buffer-limit-bytes}?
| +--rw structured-data? boolean {structured-data}?
+--rw file
| +--rw log-file* [name]
| +--rw name inet:uri
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| +--rw log-selector
| | +--rw (selector-facility)
| | | +--:(no-log-facility)
| | | | +--rw no-facilities? empty
| | | +--:(log-facility)
| | | +--rw log-facility* [facility]
| | | +--rw facility union
| | | +--rw severity union
| | | +--rw compare-op? enumeration {select-sev-compare}?
| | +--rw pattern-match? string {select-match}?
| +--rw structured-data? boolean {structured-data}?
| +--rw file-archive
| +--rw number-of-files? uint32 {file-limit-size}?
| +--rw max-file-size? uint64 {file-limit-size}?
| +--rw rollover? uint32 {file-limit-duration}?
| +--rw retention? uint16 {file-limit-duration}?
+--rw remote
| +--rw destination* [name]
| +--rw name string
| +--rw (transport)
| | +--:(tcp)
| | | +--rw tcp
| | | +--rw address? inet:host
| | | +--rw port? inet:port-number
| | +--:(udp)
| | | +--rw udp
| | | +--rw address? inet:host
| | | +--rw port? inet:port-number
| | +--:(tls)
| | +--rw tls
| | +--rw address? inet:host
| | +--rw port? inet:port-number
| +--rw log-selector
| | +--rw (selector-facility)
| | | +--:(no-log-facility)
| | | | +--rw no-facilities? empty
| | | +--:(log-facility)
| | | +--rw log-facility* [facility]
| | | +--rw facility union
| | | +--rw severity union
| | | +--rw compare-op? enumeration {select-sev-compare}?
| | +--rw pattern-match? string {select-match}?
| +--rw destination-facility? identityref
| +--rw source-interface? if:interface-ref
| +--rw structured-data? boolean {structured-data}?
| +--rw syslog-sign! {signed-messages}?
| +--rw cert-initial-repeat uint16
| +--rw cert-resend-delay uint16
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| +--rw cert-resend-count uint16
| +--rw sig-max-delay uint16
| +--rw sig-number-resends uint16
| +--rw sig-resend-delay uint16
| +--rw sig-resend-count uint16
+--rw terminal
| +--rw all-terminals!
| | +--rw log-selector
| | +--rw (selector-facility)
| | | +--:(no-log-facility)
| | | | +--rw no-facilities? empty
| | | +--:(log-facility)
| | | +--rw log-facility* [facility]
| | | +--rw facility union
| | | +--rw severity union
| | | +--rw compare-op? enumeration {select-sev-compare}?
| | +--rw pattern-match? string {select-match}?
| +--rw terminal* [name] {terminal-facility-device-logging}?
| +--rw name string
| +--rw log-selector
| +--rw (selector-facility)
| | +--:(no-log-facility)
| | | +--rw no-facilities? empty
| | +--:(log-facility)
| | +--rw log-facility* [facility]
| | +--rw facility union
| | +--rw severity union
| | +--rw compare-op? enumeration {select-sev-compare}?
| +--rw pattern-match? string {select-match}?
+--rw session
+--rw all-users!
| +--rw log-selector
| +--rw (selector-facility)
| | +--:(no-log-facility)
| | | +--rw no-facilities? empty
| | +--:(log-facility)
| | +--rw log-facility* [facility]
| | +--rw facility union
| | +--rw severity union
| | +--rw compare-op? enumeration {select-sev-compare}?
| +--rw pattern-match? string {select-match}?
+--rw user* [name] {session-facility-user-logging}?
+--rw name string
+--rw log-selector
+--rw (selector-facility)
| +--:(no-log-facility)
| | +--rw no-facilities? empty
| +--:(log-facility)
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| +--rw log-facility* [facility]
| +--rw facility union
| +--rw severity union
| +--rw compare-op? enumeration {select-sev-compare}?
+--rw pattern-match? string {select-match}?
4. SYSLOG YANG Models
4.1. SYSLOG-TYPES Module
<CODE BEGINS> file "ietf-syslog-types.yang"
module ietf-syslog-types {
namespace "urn:ietf:params:xml:ns:yang:ietf-syslog-types";
prefix syslogtypes;
organization "IETF NETMOD (NETCONF Data Modeling Language) Working
Group";
contact
"WG Web: <http://tools.ietf.org/wg/netmod/>
WG List: <mailto:netmod@ietf.org>
WG Chair: Lou Berger
<mailto:lberger@labn.net>
WG Chair: Jurgen Schonwalder
<mailto:j.schoenwaelder@jacobs-university.de>
WG Chair: Kent Watsen
<mailto:kwatsen@juniper.net>
Editor: Kiran Agrahara Sreenivasa
<mailto:kkoushik@cisco.com>
Editor: Clyde Wildes
<mailto:cwildes@cisco.com>";
description
"This module contains a collection of YANG type definitions for
SYSLOG.
Copyright (c) 2016 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).
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The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL
NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'MAY', and
'OPTIONAL' in the module text are to be interpreted as described
in RFC 2119 (http://tools.ietf.org/html/rfc2119).
This version of this YANG module is part of RFC XXXX
(http://tools.ietf.org/html/rfcXXXX); see the RFC itself for
full legal notices.";
reference
"RFC 5424: The Syslog Protocol";
revision 2016-05-10 {
description
"Initial Revision";
reference
"RFC XXXX: SYSLOG YANG Model";
}
typedef severity {
type enumeration {
enum "emergency" {
value 0;
description
"Emergency Level Msg";
}
enum "alert" {
value 1;
description
"Alert Level Msg";
}
enum "critical" {
value 2;
description
"Critical Level Msg";
}
enum "error" {
value 3;
description
"Error Level Msg";
}
enum "warning" {
value 4;
description
"Warning Level Msg";
}
enum "notice" {
value 5;
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description
"Notification Level Msg";
}
enum "info" {
value 6;
description
"Informational Level Msg";
}
enum "debug" {
value 7;
description
"Debugging Level Msg";
}
}
description
"The definitions for Syslog message severity as per RFC 5424.";
}
identity syslog-facility {
description
"This identity is used as a base for all syslog facilities as
per RFC 5424.";
}
identity kern {
base syslog-facility;
description
"The facility for kernel messages (0) as defined in RFC 5424.";
}
identity user {
base syslog-facility;
description
"The facility for user-level messages (1) as defined in RFC 5424.";
}
identity mail {
base syslog-facility;
description
"The facility for the mail system (2) as defined in RFC 5424.";
}
identity daemon {
base syslog-facility;
description
"The facility for the system daemons (3) as defined in RFC 5424.";
}
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identity auth {
base syslog-facility;
description
"The facility for security/authorization messages (4) as defined
in RFC 5424.";
}
identity syslog {
base syslog-facility;
description
"The facility for messages generated internally by syslogd
facility (5)as defined in RFC 5424.";
}
identity lpr {
base syslog-facility;
description
"The facility for the line printer subsystem (6) as defined in
RFC 5424.";
}
identity news {
base syslog-facility;
description
"The facility for the network news subsystem (7) as defined in
RFC 5424.";
}
identity uucp {
base syslog-facility;
description
"The facility for the UUCP subsystem (8) as defined in RFC 5424.";
}
identity cron {
base syslog-facility;
description
"The facility for the clock daemon (9) as defined in RFC 5424.";
}
identity authpriv {
base syslog-facility;
description
"The facility for privileged security/authorization messages (10)
as defined in RFC 5424.";
}
identity ftp {
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base syslog-facility;
description
"The facility for the FTP daemon (11) as defined in RFC 5424.";
}
identity ntp {
base syslog-facility;
description
"The facility for the NTP subsystem (12) as defined in RFC 5424.";
}
identity audit {
base syslog-facility;
description
"The facility for log audit messages (13) as defined in RFC 5424.";
}
identity console {
base syslog-facility;
description
"The facility for log alert messages (14) as defined in RFC 5424.";
}
identity cron2 {
base syslog-facility;
description
"The facility for the second clock daemon (15) as defined in
RFC 5424.";
}
identity local0 {
base syslog-facility;
description
"The facility for local use 0 messages (16) as defined in
RFC 5424.";
}
identity local1 {
base syslog-facility;
description
"The facility for local use 1 messages (17) as defined in
RFC 5424.";
}
identity local2 {
base syslog-facility;
description
"The facility for local use 2 messages (18) as defined in
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RFC 5424.";
}
identity local3 {
base syslog-facility;
description
"The facility for local use 3 messages (19) as defined in
RFC 5424.";
}
identity local4 {
base syslog-facility;
description
"The facility for local use 4 messages (20) as defined in
RFC 5424.";
}
identity local5 {
base syslog-facility;
description
"The facility for local use 5 messages (21) as defined in
RFC 5424.";
}
identity local6 {
base syslog-facility;
description
"The facility for local use 6 messages (22) as defined in
RFC 5424.";
}
identity local7 {
base syslog-facility;
description
"The facility for local use 7 messages (23) as defined in
RFC 5424.";
}
}
<CODE ENDS>
4.2. Syslog Module
<CODE BEGINS> file "ietf-syslog.yang"
module ietf-syslog {
namespace "urn:ietf:params:xml:ns:yang:ietf-syslog";
prefix syslog;
import ietf-inet-types {
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prefix inet;
}
import ietf-interfaces {
prefix if;
}
import ietf-syslog-types {
prefix syslogtypes;
}
organization "IETF NETMOD (NETCONF Data Modeling Language)
Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/netmod/>
WG List: <mailto:netmod@ietf.org>
WG Chair: Lou Berger
<mailto:lberger@labn.net>
WG Chair: Jurgen Schonwalder
<mailto:j.schoenwaelder@jacobs-university.de>
WG Chair: Kent Watsen
<mailto:kwatsen@juniper.net>
Editor: Kiran Agrahara Sreenivasa
<mailto:kkoushik@cisco.com>
Editor: Clyde Wildes
<mailto:cwildes@cisco.com>";
description
"This module contains a collection of YANG definitions
for Syslog configuration.
Copyright (c) 2015 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).
The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL
NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'MAY', and
'OPTIONAL' in the module text are to be interpreted as described
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in RFC 2119 (http://tools.ietf.org/html/rfc2119).
This version of this YANG module is part of RFC XXXX
(http://tools.ietf.org/html/rfcXXXX); see the RFC itself for
full legal notices.";
reference
"RFC 5424: The Syslog Protocol
RFC 5848: Signed Syslog Messages";
revision 2016-03-20{
description
"Initial Revision";
reference
"RFC XXXX: SYSLOG YANG Model";
}
feature console-action {
description
"This feature indicates that logging to the console is
supported.";
}
feature buffer-action {
description
"This feature indicates that logging to an in-memory
buffer is supported.";
}
feature buffer-limit-bytes {
description
"This feature indicates that local memory logging buffers
are limited in size using a limit expressed in bytes.";
}
feature buffer-limit-messages {
description
"This feature indicates that local memory logging buffers
are limited in size using a limit expressed in number
of messages.";
}
feature file-limit-size {
description
"This feature indicates that file logging resources
are managed using size and number limits.";
}
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feature file-limit-duration {
description
"This feature indicates that file logging resources
are managed using time based limits.";
}
feature terminal-action {
description
"This feature indicates that logging to a terminal
is supported.";
}
feature terminal-facility-user-logging-config {
description
"This feature represents the ability to adjust
log message settings for individual terminal
devices.";
}
feature session-action {
description
"This feature indicates that logging to user
CLI session is supported.";
}
feature session-facility-user-logging-config {
description
"This feature represents the ability to adjust
log message settings for individual user CLI
sessions.";
}
feature selector-sevop-config {
description
"This feature represents the ability to select messages
using the additional operators equal to, or not equal to
when comparing the Syslog message severity.";
}
feature selector-match-config {
description
"This feature represents the ability to select messages based
on a Posix 1003.2 regular expression pattern match.";
}
feature structured-data-config {
description
"This feature represents the ability to log messages
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in structured-data format as per RFC 5424.";
}
feature signed-messages-config {
description
"This feature represents the ability to configure signed
syslog messages according to RFC 5848.";
}
grouping syslog-severity {
description
"This grouping defines the Syslog severity which is used to
select log messages.";
leaf severity {
type union {
type syslogtypes:severity;
type enumeration {
enum all {
value -1;
description
"This enum describes the case where all severities
are selected.";
}
enum none {
value -2;
description
"This enum describes the case where no severities
are selected.";
}
}
}
mandatory true;
description
"This leaf specifies the Syslog message severity. When
severity is specified, the default severity comparison
is all messages of the specified severity and greater are
selected. 'all' is a special case which means all severities
are selected. 'none' is a special case which means that
no selection should occur or disable this filter.";
}
leaf severity-operator {
when '../severity != "all" and
../severity != "none"' {
description
"The severity-operator is not applicable for severity 'all' or
severity 'none'";
}
if-feature selector-sevop-config;
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type enumeration {
enum equals-or-higher {
description
"This enum specifies all messages of the specified
severity and higher are logged according to the
given log-action";
}
enum equals {
description
"This enum specifies all messages that are for
the specified severity are logged according to the
given log-action";
}
enum not-equals {
description
"This enum specifies all messages that are not for
the specified severity are logged according to the
given log-action";
}
}
default equals-or-higher;
description
"This leaf describes the option to specify how the
severity comparison is performed.";
}
}
grouping syslog-selector {
description
"This grouping defines a Syslog selector which is used to
select log messages for the log-action (buffer, file,
etc). Choose one of the following:
no-log-facility
log-facility [<facility> <severity>...]";
container log-selector {
description
"This container describes the log selector parameters
for Syslog.";
choice selector-facility {
mandatory true;
description
"This choice describes the option to specify no
facilities, or a specific facility which can be
all for all facilities.";
case no-log-facility {
description
"This case specifies no facilities will match when
comparing the Syslog message facility. This is a
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method that can be used to effectively disable a
particular log-action (buffer, file, etc).";
leaf no-facilities {
type empty;
description
"This leaf specifies that no facilities are selected
for this log-action.";
}
}
case log-facility {
description
"This case specifies one or more specified facilities
will match when comparing the Syslog message facility.";
list log-facility {
key facility;
description
"This list describes a collection of Syslog
facilities and severities.";
leaf facility {
type union {
type identityref {
base syslogtypes: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 syslog-severity;
}
}
}
leaf pattern-match {
if-feature selector-match-config;
type string;
description
"This leaf desribes a Posix 1003.2 regular expression
string that can be used to select a Syslog message for
logging. The match is performed on the RFC 5424
SYSLOG-MSG field.";
}
}
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}
grouping syslog-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-config;
type boolean;
default false;
description
"This leaf describes how log messages are written to
the log file. If true, messages will be written
with one or more STRUCTURED-DATA elements as per
RFC5424; if false, messages will be written with
STRUCTURED-DATA = NILVALUE.";
}
}
container syslog {
description
"This container describes the configuration parameters for
Syslog.";
container log-actions {
description
"This container describes the log-action parameters
for Syslog.";
container console {
if-feature console-action;
presence "Enables logging console configuration";
description
"This container describes the configuration parameters for
console logging.";
uses syslog-selector;
}
container buffer {
if-feature buffer-action;
description
"This container describes the configuration parameters for
local memory buffer logging. The buffer is circular in
nature, so newer messages overwrite older messages after
the buffer is filled. The method used to read syslog messages
from the buffer is supplied by the local implementation.";
list log-buffer {
key name;
description
"This list describes a collection of local logging
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memory buffers. If buffer size limits are not supplied, it
is assumed that the local implementation defined
limits will be used.";
leaf name {
type string;
description
"This leaf specifies the name of the log buffer.";
}
uses syslog-selector;
leaf buffer-size-bytes {
if-feature buffer-limit-bytes;
type uint64;
units "bytes";
description
"This leaf configures the amount of memory (in bytes) that
will be dedicated to the local memory logging buffer.
The default value varies by implementation.";
}
leaf buffer-size-messages {
if-feature buffer-limit-messages;
type uint64;
units "log messages";
description
"This leaf configures the amount number of log messages that
can be stored in the local memory logging buffer. The
default value varies by implementation.";
}
uses syslog-structured-data;
}
}
container file {
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:.";
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}
uses syslog-selector;
uses syslog-structured-data;
container file-archive {
description
"This container describes the configuration
parameters for log file archiving.";
leaf number-of-files {
if-feature file-limit-size;
type uint32;
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 uint64;
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 uint16;
units "hours";
description
"This leaf specifies the length of time that
completed/closed log event files should be stored
in the file system before they are deleted.";
}
}
}
}
container remote {
description
"This container describes the configuration parameters for
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remote logging.";
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 tcp {
container tcp {
description
"This container describes the TCP transport
options.";
reference
"RFC 6587: Transmission of Syslog Messages over TCP";
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 udp {
container udp {
description
"This container describes the UDP transport
options.";
reference
"RFC 5426: Transmission of Syslog Messages over UDP";
leaf address {
type inet:host;
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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 ";
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
"This leaf specifies the port number used to
deliver messages to the remote server.";
}
}
}
}
uses syslog-selector;
leaf destination-facility {
type identityref {
base syslogtypes:syslog-facility;
}
default syslogtypes:local7;
description
"This leaf specifies the facility used in messages
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delivered to the remote server.";
}
leaf source-interface {
type if:interface-ref;
description
"This leaf sets the source interface for the remote
Syslog server. Either the interface name or the
interface IP address can be specified. If not set,
messages sent to a remote syslog server will
contain the IP address of the interface the syslog
message uses to exit the network element";
}
uses syslog-structured-data;
container syslog-sign {
if-feature signed-messages-config;
presence
"If present, syslog-sign is activated.";
description
"This container describes the configuration
parameters for signed syslog messages as described
by RFC 5848.";
reference
"RFC 5848: Signed Syslog Messages";
leaf cert-initial-repeat {
type uint16;
mandatory true;
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 uint16;
mandatory true;
description
"This leaf specifies the maximum time delay in
seconds until resending the Certificate Block.";
}
leaf cert-resend-count {
type uint16;
mandatory true;
description
"This leaf specifies the maximum number of other
syslog messages to send until resending the
Certificate Block.";
}
leaf sig-max-delay {
type uint16;
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mandatory true;
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 uint16;
mandatory true;
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 [RFC5426] is used.).";
}
leaf sig-resend-delay {
type uint16;
mandatory true;
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 uint16;
mandatory true;
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.";
}
}
}
}
container terminal {
if-feature terminal-action;
description
"This container describes the configuration parameters for
the terminal logging configuration.";
container all-terminals {
presence "Enables logging to all terminals.";
description
"This container describes the configuration
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parameters for all terminals.";
uses syslog-selector;
}
list terminal {
if-feature terminal-facility-user-logging-config;
key "name";
description
"This list describes a collection of ";
leaf name {
type string;
description
"This leaf uniquely describes a terminal which
will receive log messages.";
}
uses syslog-selector;
}
}
container session {
if-feature session-action;
description
"This container describes the configuration parameters for
user CLI session logging configuration.";
container all-users {
presence "Enables logging to all user sessions.";
description
"This container describes the configuration
parameters for all users.";
uses syslog-selector;
}
list user {
if-feature session-facility-user-logging-config;
key "name";
description
"This list describes a collection of user names.";
leaf name {
type string;
description
"This leaf uniquely describes a user name which
is the login name of the user whose session
is to receive log messages.";
}
uses syslog-selector;
}
}
}
}
}
<CODE ENDS>
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4.3. A Syslog Example
Requirement:
Enable console logging of syslogs of severity critical
Here is the example syslog configuration xml:
<rpc message-id="101" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<edit-config>
<target>
<candidate/>
</target>
<config xmlns:xc="urn:ietf:params:xml:ns:netconf:base:1.0">
<syslog xmlns="urn:ietf:params:xml:ns:yang:ietf-syslog"
xmlns:syslog="urn:ietf:params:xml:ns:yang:ietf-syslog">
<log-actions>
<console>
<log-selector>
<log-facility>
<facility>all</facility>
<severity>critical</severity>
</log-facility>
</log-selector>
</console>
</log-actions>
</syslog>
</config>
</edit-config>
</rpc>
<?xml version="1.0" encoding="UTF-8"?>
<rpc-reply message-id="101" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ok/>
</rpc-reply>
Enable remote logging of syslogs to udp destination 1.1.1.1
for facility auth, severity error
<rpc message-id="101" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<edit-config>
<target>
<candidate/>
</target>
<config xmlns:xc="urn:ietf:params:xml:ns:netconf:base:1.0">
<syslog xmlns="urn:ietf:params:xml:ns:yang:ietf-syslog"
xmlns:syslog="urn:ietf:params:xml:ns:yang:ietf-syslog">
<log-actions>
<remote>
<destination>
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<name>remote1</name>
<udp>
<address>1.1.1.1</address>
</udp>
<log-selector>
<log-facility>
<facility xmlns:syslogtypes=
"urn:ietf:params:xml:ns:yang:ietf-syslog-types">
syslogtypes:auth</facility>
<severity>error</severity>
</log-facility>
</log-selector>
</destination>
</remote>
</log-actions>
</syslog>
</config>
</edit-config>
</rpc>
<?xml version="1.0" encoding="UTF-8"?>
<rpc-reply message-id="101" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ok/>
</rpc-reply>
5. Acknowledgements
The authors wish to thank the following who commented on versions 01
through 06 of this proposal:
Martin Bjorklund
Jim Gibson
Jeffrey Haas
John Heasley
Giles Heron
Lisa Huang
Mahesh Jethanandani
Jeffrey K Lange
Jan Lindblad
Chris Lonvick
Tom Petch
Juergen Schoenwaelder
Jason Sterne
Peter Van Horne
Bert Wijnen
Aleksandr Zhdankin
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6. IANA Considerations
This document registers two URIs in the IETF XML registry [RFC3688].
Following the format in RFC 3688, the following registration is
requested to be made:
URI: urn:ietf:params:xml:ns:yang:ietf-syslog-types
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
This document registers a YANG module in the YANG Module Names
registry [RFC6020].
name: ietf-syslog-types namespace: urn:ietf:params:xml:ns:yang:ietf-
syslog-types
prefix: ietf-syslog-types reference: RFC XXXX
Following the format in RFC 3688, the following registration is
requested to be made:
URI: urn:ietf:params:xml:ns:yang:ietf-syslog
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
This document registers a YANG module in the YANG Module Names
registry [RFC6020].
name: ietf-syslog namespace: urn:ietf:params:xml:ns:yang:ietf-syslog
prefix: ietf-syslog
reference: RFC XXXX
7. Security Considerations
The YANG module defined in this memo is designed to be accessed via
the NETCONF protocol [RFC6241]. The lowest NETCONF layer is the
secure transport layer and the mandatory-to-implement secure
transport is SSH [RFC6242]. The NETCONF access control model
[RFC6536] provides the means to restrict access for particular
NETCONF users to a pre-configured subset of all available NETCONF
protocol operations and content.
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There are a number of data nodes defined in the YANG module which are
writable/creatable/deletable (i.e., config true, which is the
default). These data nodes may be considered sensitive or vulnerable
in some network environments. Write operations (e.g., <edit-config>)
to these data nodes without proper protection can have a negative
effect on network operations.
8. References
8.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC5424] Gerhards, R., "The Syslog Protocol", RFC 5424,
DOI 10.17487/RFC5424, March 2009,
<http://www.rfc-editor.org/info/rfc5424>.
[RFC5425] Miao, F., Ed., Ma, Y., Ed., and J. Salowey, Ed.,
"Transport Layer Security (TLS) Transport Mapping for
Syslog", RFC 5425, DOI 10.17487/RFC5425, March 2009,
<http://www.rfc-editor.org/info/rfc5425>.
[RFC5426] Okmianski, A., "Transmission of Syslog Messages over UDP",
RFC 5426, DOI 10.17487/RFC5426, March 2009,
<http://www.rfc-editor.org/info/rfc5426>.
[RFC5848] Kelsey, J., Callas, J., and A. Clemm, "Signed Syslog
Messages", RFC 5848, DOI 10.17487/RFC5848, May 2010,
<http://www.rfc-editor.org/info/rfc5848>.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<http://www.rfc-editor.org/info/rfc6241>.
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
<http://www.rfc-editor.org/info/rfc6242>.
[RFC6587] Gerhards, R. and C. Lonvick, "Transmission of Syslog
Messages over TCP", RFC 6587, DOI 10.17487/RFC6587, April
2012, <http://www.rfc-editor.org/info/rfc6587>.
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8.2. Informative References
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<http://www.rfc-editor.org/info/rfc3688>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<http://www.rfc-editor.org/info/rfc6020>.
Appendix A. Implementor Guidelines
A.1. Extending Facilities
Many vendors extend the list of facilities available for logging in
their implementation. Here is an example that shows how additional
facilities could be added to the list of available facilities (in
this case two facilities are added):
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module vendor-syslog-types-example {
namespace "urn:vendor:params:xml:ns:yang:vendor-syslog-types";
prefix vendor-syslogtypes;
import ietf-syslog-types {
prefix syslogtypes;
}
organization "Vendor, Inc.";
contact
"Vendor, Inc.
Customer Service
E-mail: syslog-yang@vendor.com";
description
"This module contains a collection of vendor-sprecific YANG type
definitions for SYSLOG.";
revision 2016-03-20 {
description
"Version 1.0";
reference
"Vendor SYSLOG Types: SYSLOG YANG Model";
}
identity vendor_specific_type_1 {
base syslogtypes:syslog-facility;
}
identity vendor_specific_type_2 {
base syslogtypes:syslog-facility;
}
}
Authors' Addresses
Clyde Wildes (editor)
Cisco Systems Inc.
170 West Tasman Drive
San Jose, CA 95134
US
Phone: +1 408 527-2672
Email: cwildes@cisco.com
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Kiran Koushik (editor)
Cisco Systems Inc.
12515Research Blvd., Building 4
Austin, TX 78759
US
Phone: +1 512 378-1482
Email: kkoushik@cisco.com
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