SYSLOG YANG model
draft-ietf-netmod-syslog-model-06
The information below is for an old version of the document.
| Document | Type | Active Internet-Draft (netmod WG) | |
|---|---|---|---|
| Author | Clyde Wildes | ||
| Last updated | 2016-02-22 (Latest revision 2015-12-22) | ||
| Replaces | draft-wildes-netmod-syslog-model | ||
| Stream | Internet Engineering Task Force (IETF) | ||
| Formats | plain text htmlized pdfized bibtex | ||
| Reviews |
SECDIR Last Call review
(of
-21)
Has Issues
YANGDOCTORS Last Call review
(of
-17)
Ready with Issues
|
||
| Stream | WG state | WG Document | |
| Document shepherd | Lou Berger | ||
| IESG | IESG state | I-D Exists | |
| Consensus boilerplate | Unknown | ||
| Telechat date | (None) | ||
| Responsible AD | Benoît Claise | ||
| Send notices to | "Lou Berger" <lberger@labn.net> |
draft-ietf-netmod-syslog-model-06
NETMOD WG Clyde Wildes
Internet-Draft Kiran Koushik
Intended status: Informational Cisco Systems Inc.
Expires: Jun 16, 2016 Dec 23, 2015
SYSLOG YANG model
draft-ietf-netmod-syslog-model-06
Abstract
This document describes a data model for 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 Jun 16, 2016.
Copyright Notice
Copyright (c) 2015 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.
Wildes, et al. Expires Jun 16, 2016 [Page 1]
Internet-Draft SYSLOG YANG model Dec 2015
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Definitions and Acronyms . . . . . . . . . . . . . . . . 3
2. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 3
3. Design of the SYSLOG Model . . . . . . . . . . . . . . . . . 3
3.1. SYSLOG Module . . . . . . . . . . . . . . . . . . . . . . 4
4. SYSLOG YANG Models . . . . . . . . . . . . . . . . . . . . . 6
4.1. SYSLOG TYPES Module . . . . . . . . . . . . . . . . . . . 6
4.2. SYSLOG module . . . . . . . . . . . . . . . . . . . . . . 10
4.3. A SYSLOG Example . . . . . . . . . . . . . . . . . . . . 18
5. Implementation Status . . . . . . . . . . . . . . . . . . . . 19
6. Security Considerations . . . . . . . . . . . . . . . . . . . 19
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 20
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 20
9. Change log [RFC Editor: Please remove] . . . . . . . . . . . 20
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 20
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 21
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
draft.
Wildes, et al. Expires Jun 16, 2016 [Page 2]
Internet-Draft SYSLOG YANG model Dec 2015
1.1. Definitions and Acronyms
IP: Internet Protocol
IPv4: Internet Protocol version 4
IPv6: Internet Protocol version 6
UDP: User Datagram Protocol
VRF: Virtual Routing and Forwarding
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.
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 all vendors 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 producers, a group level suppression filter,
and message distributors. The following digram shows syslog messages
flowing from a message producer, through the group level suppression
filter, and if passed by the group filter to message distributors where
further suppression filtering can take place.
Wildes, et al. Expires Jun 16, 2016 [Page 3]
Internet-Draft SYSLOG YANG model Dec 2015
Message Producers
+-------------+ +-------------+ +-------------+ +-------------+
| 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(s)| | File(s) | |
+----------+ +----------+ +----------+ |
+-------------+-------------+
| | |
v v v
+-------------+ +-----------+ +-----------+
|Remote | | | |User |
|Collectors(s)| |Terminal(s)| |Sessions(s)|
+-------------+ +-----------+ +-----------+
The leaves in the base syslog model correspond to the group level
suppression filter and each message distributor:
- console
- log buffer(s)
- log file(s)
- remote collector(s)
- terminal(s)
- user session(s).
Optional features are used to specified fields that are not present in
all vendor configurations.
Wildes, et al. Expires Jun 16, 2016 [Page 4]
Internet-Draft SYSLOG YANG model Dec 2015
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 "{...}?"
module: ietf-syslog
+--rw syslog
+--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 severity-operator? enumeration {selector-severity-operator-config}?
| +--rw pattern-match? string {selector-match-processing-config}?
+--rw buffer
| +--rw log-buffer* [name]
| +--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 severity-operator? enumeration {selector-severity-operator-config}?
| | +--rw pattern-match? string {selector-match-processing-config}?
| +--rw buffer-size-bytes? uint64 {buffer-limit-bytes}?
| +--rw buffer-size-messages? uint64 {buffer-limit-messages}?
+--rw file
| +--rw log-file* [name]
| +--rw name inet:uri
| +--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 severity-operator? enumeration {selector-severity-operator-config}?
| | +--rw pattern-match? string {selector-match-processing-config}?
| +--rw structured-data? boolean {structured-data-config}?
| +--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
| +--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 severity-operator? enumeration {selector-severity-operator-config}?
| | +--rw pattern-match? string {selector-match-processing-config}?
| +--rw destination-facility? identityref
| +--rw source-interface? if:interface-ref
| +--rw syslog-sign! {signed-messages-config}?
| +--rw cert-initial-repeat uint16
| +--rw cert-resend-delay uint16
| +--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 (terminal-scope)
| +--:(all-terminals)
| | +--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 severity-operator? enumeration {selector-severity-operator-config}?
| | +--rw pattern-match? string {selector-match-processing-config}?
| +--:(per-terminal) {terminal-facility-user-logging-config}?
| +--rw device-name* [dname]
| +--rw dname 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 severity-operator? enumeration {selector-severity-operator-config}?
| +--rw pattern-match? string {selector-match-processing-config}?
+--rw session
+--rw (user-scope)
+--:(all-users)
| +--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 severity-operator? enumeration {selector-severity-operator-config}?
| +--rw pattern-match? string {selector-match-processing-config}?
+--:(per-user) {session-facility-user-logging-config}?
+--rw user-name* [uname]
+--rw uname 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 severity-operator? enumeration {selector-severity-operator-config}?
+--rw pattern-match? string {selector-match-processing-config}?
Wildes, et al. Expires Jun 16, 2016 [Page 5]
Internet-Draft SYSLOG YANG model Dec 2015
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: Tom Nadeau
<mailto:tnadeau@lucidvision.com>
WG Chair: Kent Watsen
<mailto:kwatsen@juniper.net>
Editor: Ladislav Lhotka
<mailto:lhotka@nic.cz>";
description
"This module contains a collection of YANG type definitions for
SYSLOG.";
revision 2015-11-09 {
description
"Initial Revision";
reference
"This model references RFC 5424 - The Syslog Protocol,
and RFC 5848 - Signed Syslog Messages.";
}
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";
}
Wildes, et al. Expires Jun 16, 2016 [Page 6]
Internet-Draft SYSLOG YANG model Dec 2015
enum "warning" {
value 4;
description
"Warning Level Msg";
}
enum "notice" {
value 5;
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
"The base identity to represent syslog facilities";
}
identity kern {
base syslog-facility;
description
"The facility for kernel messages as defined in RFC 5424.";
}
identity user {
base syslog-facility;
description
"The facility for user-level messages as defined in RFC 5424.";
}
identity mail {
base syslog-facility;
description
"The facility for the mail system as defined in RFC 5424.";
}
identity daemon {
base syslog-facility;
description
"The facility for the system daemons as defined in RFC 5424.";
}
identity auth {
base syslog-facility;
description
"The facility for security/authorization messages as defined
in RFC 5424.";
}
Wildes, et al. Expires Jun 16, 2016 [Page 7]
Internet-Draft SYSLOG YANG model Dec 2015
identity syslog {
base syslog-facility;
description
"The facility for messages generated internally by syslogd
facility as defined in RFC 5424.";
}
identity lpr {
base syslog-facility;
description
"The facility for the line printer subsystem as defined in
RFC 5424.";
}
identity news {
base syslog-facility;
description
"The facility for the network news subsystem as defined in
RFC 5424.";
}
identity uucp {
base syslog-facility;
description
"The facility for the UUCP subsystem as defined in RFC 5424.";
}
identity cron {
base syslog-facility;
description
"The facility for the clock daemon as defined in RFC 5424.";
}
identity authpriv {
base syslog-facility;
description
"The facility for privileged security/authorization messages
as defined in RFC 5424.";
}
identity ftp {
base syslog-facility;
description
"The facility for the FTP daemon as defined in RFC 5424.";
}
identity ntp {
base syslog-facility;
description
"The facility for the NTP subsystem as defined in RFC 5424.";
}
identity audit {
base syslog-facility;
description
"The facility for log audit messages as defined in RFC 5424.";
}
Wildes, et al. Expires Jun 16, 2016 [Page 8]
Internet-Draft SYSLOG YANG model Dec 2015
identity console {
base syslog-facility;
description
"The facility for log alert messages as defined in RFC 5424.";
}
identity cron2 {
base syslog-facility;
description
"The facility for the second clock daemon as defined in
RFC 5424.";
}
identity local0 {
base syslog-facility;
description
"The facility for local use 0 messages as defined in
RFC 5424.";
}
identity local1 {
base syslog-facility;
description
"The facility for local use 1 messages as defined in
RFC 5424.";
}
identity local2 {
base syslog-facility;
description
"The facility for local use 2 messages as defined in
RFC 5424.";
}
identity local3 {
base syslog-facility;
description
"The facility for local use 3 messages as defined in
RFC 5424.";
}
identity local4 {
base syslog-facility;
description
"The facility for local use 4 messages as defined in
RFC 5424.";
}
identity local5 {
base syslog-facility;
description
"The facility for local use 5 messages as defined in
RFC 5424.";
}
identity local6 {
base syslog-facility;
description
"The facility for local use 6 messages as defined in
RFC 5424.";
}
identity local7 {
base syslog-facility;
description
"The facility for local use 7 messages as defined in
RFC 5424.";
}
}
<CODE ENDS>
Wildes, et al. Expires Jun 16, 2016 [Page 9]
Internet-Draft SYSLOG YANG model Dec 2015
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 {
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: Tom Nadeau
<mailto:tnadeau@lucidvision.com>
WG Chair: Kent Watsen
<mailto:kwatsen@juniper.net>
Editor: Ladislav Lhotka
<mailto:lhotka@nic.cz>";
description
"This module contains a collection of YANG definitions
for Syslog configuration.";
revision 2015-11-09 {
description
"Initial Revision";
reference
"RFC 5424: The Syslog Protocol
RFC 5848: Signed Syslog Messages";
}
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 structured-data-config {
description
"This feature represents the ability to log messages
in structured-data format as per RFC 5424.";
}
Wildes, et al. Expires Jun 16, 2016 [Page 10]
Internet-Draft SYSLOG YANG model Dec 2015
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 terminal-facility-user-logging-config {
description
"This feature represents the ability to adjust
log message settings for individual terminal
devices.";
}
feature session-facility-user-logging-config {
description
"This feature represents the ability to adjust
log message settings for individual user sessions.";
}
feature selector-severity-operator-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-processing-config {
description
"This feature represents the ability to select messages based
on a Posix 1003.2 regular expression pattern match.";
}
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 requested.";
}
enum none {
value -2;
description
"This enum describes the case where no severities
are requested.";
}
}
}
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
logged. 'all' is a special case which means all severities
are requested. 'none' is a special case which means that
no severity selection should occur.";
}
Wildes, et al. Expires Jun 16, 2016 [Page 11]
Internet-Draft SYSLOG YANG model Dec 2015
leaf severity-operator {
if-feature selector-severity-operator-config;
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
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.";
}
}
Wildes, et al. Expires Jun 16, 2016 [Page 12]
Internet-Draft SYSLOG YANG model Dec 2015
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-processing-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.";
}
}
}
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 {
presence "Enables logging console configuration";
description
"This container describes the configuration parameters for
console logging.";
uses syslog-selector;
}
Wildes, et al. Expires Jun 16, 2016 [Page 13]
Internet-Draft SYSLOG YANG model Dec 2015
container buffer {
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.";
list log-buffer {
key name;
description
"This list describes a collection of local logging
memory buffers.";
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.";
}
}
}
container file {
description
"This container describes the configuration parameters for
file logging.";
list log-file {
key "name";
description
"This list describes a collection of local logging
files.";
leaf name {
type inet:uri;
description
"This leaf specifies the name of the log file which
MUST use the uri scheme file:.";
}
Wildes, et al. Expires Jun 16, 2016 [Page 14]
Internet-Draft SYSLOG YANG model Dec 2015
uses syslog-selector;
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 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.";
}
}
}
}
Wildes, et al. Expires Jun 16, 2016 [Page 15]
Internet-Draft SYSLOG YANG model Dec 2015
container remote {
description
"This container describes the configuration parameters for
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.";
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.";
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.";
}
}
}
}
Wildes, et al. Expires Jun 16, 2016 [Page 16]
Internet-Draft SYSLOG YANG model Dec 2015
uses syslog-selector;
leaf destination-facility {
type identityref {
base syslogtypes:syslog-facility;
}
default syslogtypes:local7;
description
"This leaf specifies the facility used in messages
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";
}
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;
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.";
}
Wildes, et al. Expires Jun 16, 2016 [Page 17]
Internet-Draft SYSLOG YANG model Dec 2015
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 {
description
"This container describes the configuration parameters for
the terminal logging configuration.";
choice terminal-scope {
mandatory true;
description
"This choice describes the option to specify all
terminals or a specific terminal. The all terminals
case implies that messages will be sent to all
sessions on that terminal";
case all-terminals {
description
"This case specifies all terminals.";
container all-terminals {
description
"This container describes the configuration
parameters for all terminals.";
uses syslog-selector;
}
}
case per-terminal {
if-feature terminal-facility-user-logging-config;
description
"This case specifies one or more terminals.";
list device-name {
key "dname";
description
"This list describes a collection of device names.";
leaf dname {
type string;
description
"This leaf uniquely describes a device name which
is the device to receive log messages.";
}
uses syslog-selector;
}
}
}
}
container session {
description
"This container describes the configuration parameters for
session logging configuration.";
choice user-scope {
mandatory true;
description
"This choice describes the option to specify all users
or a specific user. The all users case implies that
messages will be sent to all sessions";
case all-users {
description
"This case specifies all users.";
container all-users {
description
"This container describes the configuration
parameters for all users.";
uses syslog-selector;
}
}
case per-user {
if-feature session-facility-user-logging-config;
description
"This case specifies a specific user.";
list user-name {
key "uname";
description
"This list describes a collection of user names.";
leaf uname {
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>
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>
Wildes, et al. Expires Jun 16, 2016 [Page 18]
Internet-Draft SYSLOG YANG model Dec 2015
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>
<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. Implementation Status
[Note to RFC Editor: Please remove this section before publication.]
This section records the status of known implementations of the Syslog
YANG model at the time of posting of this Internet-Draft.
Cisco Systems, Inc. has implemented the proposed IETF Syslog model
for the Nexus 7000 NXOS OS as a prototype, together with an
augmentation model for operating system specific Syslog configuration
features.
Five leaves were implemented in the base IETF model and three leaves
were implemented in the Cisco specific augmentation model as follows:
Leaf XPATH Sample NXOS CLI Command(s)
syslog:log-actions/console logging console 1
syslog:log-actions/file logging logfile mylog.log 2 4096
syslog:log-actions/terminal logging monitor 2
syslog:log-actions/remote *logging server server.cisco.com 2
facility user
*logging source-interface loopback 0
cisco-syslog:logging-timestamp-config logging timestamp milli-seconds
cisco-syslog:origin-id-cfg logging origin-id string abcdef
cisco-syslog:module-logging logging module 1
*The "logging server" and "logging source-interface" commands were
combined into one base model leaf.
The description of implementations in this section is intended to assist
the IETF in its decision processes in progressing drafts to RFCs.
6. Security Considerations
The YANG module defined in this memo is designed to be accessed via
the NETCONF protocol [RFC6241] [RFC6241]. The lowest NETCONF layer
is the secure transport layer and the mandatory-to-implement secure
transport is SSH [RFC6242] [RFC6242]. The NETCONF access control
model [RFC6536] [RFC6536] provides the means to restrict access for
particular NETCONF users to a pre-configured subset of all available
NETCONF protocol operations and content.
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.
TBD: List specific Subtrees and data nodes and their sensitivity/
vulnerability.
Wildes, et al. Expires Jun 16, 2016 [Page 19]
Internet-Draft SYSLOG YANG model Dec 2015
7. IANA Considerations
This document registers a URI in the IETF XML registry [RFC3688]
[RFC3688]. Following the format in RFC 3688, the following
registration is requested to be made:
URI: urn:ietf:params:xml:ns:yang: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: syslog namespace: urn:ietf:params:xml:ns:yang:syslog
prefix: syslog reference: RFC XXXX
8. Acknowledgements
The authors wish to thank the following who commented on versions 01 through 05
of this proposal:
Martin Bjorklund <mbjorklu@cisco.com>
Jim Gibson <gibson@cisco.com>
Jeffrey Haas <jhaas@pfrc.org>
John Heasley <heas@shrubbery.net>
Giles Heron <giheron@cisco.com>
Lisa Huang <yihuan@cisco.com>
Jeffrey K Lange <jeffrey.K.lange@ge.com>
Jan Lindblad <jlindbla@cisco.com>
Chris Lonvick <lonvick@gmail.com>
Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>
Jason Sterne <jason.sterne@alcatel-lucent.com>
Peter Van Horne <petervh@cisco.com>
Bert Wijnen <bertietf@bwijnen.net>
Aleksandr Zhdankin <azhdanki@cisco.com>
9. Change log [RFC Editor: Please remove]
10. References
[RFC5424] Gerhards, R., "The Syslog Protocol", BCP 78, RFC 5424,
March 2009.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
March 2004.
[RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the
Network Configuration Protocol (NETCONF)", RFC 6020,
October 2010.
[RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J., and A.
Bierman, "Network Configuration Protocol (NETCONF)", RFC
6241, June 2011.
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, June 2011.
Wildes, et al. Expires Jun 16, 2016 [Page 20]
Internet-Draft SYSLOG YANG model Dec 2015
[RFC6536] Bierman, A. and M. Bjorklund, "Network Configuration
Protocol (NETCONF) Access Control Model", RFC 6536, March
2012.
Authors' Addresses
Clyde Wildes
Cisco Systems Inc.
Email: cwildes@cisco.com
Kiran Agrahara Sreenivasa
Cisco Systems, Inc.
Email: kkoushik@cisco.com
Wildes, et al. Expires Jun 16, 2016 [Page 21]