NETMOD WG Clyde Wildes
Internet-Draft Cisco Systems
Intended status: Informational Agrahara Kiran Koushik
Expires: Sep 05, 2015 Brocade Communication Systems
Mar 05, 2015
SYSLOG YANG model
draft-ietf-netmod-syslog-model-02
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 Sep 05, 2015.
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
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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. 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 [RFC3164] in this
draft.
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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.
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Message Producers
+-------------+ +-------------+ +-------------+ +-------------+
| Various | | OS | | | | Remote |
| Components | | Kernel | | Line Cards | | Servers |
+-------------+ +-------------+ +-------------+ +-------------+
+-------------+ +-------------+ +-------------+ +-------------+
| SNMP | | Interface | | Standby | | Syslog |
| Events | | Events | | Supervisor | | Itself |
+-------------+ +-------------+ +-------------+ +-------------+
| |
+----------------------------------------------------------------+
|
|
v
Group Level Suppression
+------------------------------+
| Filter by message facility |
| and message severity |
+------------------------------+
|
|
|
+------------+------------+------------+-----------+
| | | | |
v v v v v
Message Distributors
+----------+ +----------+ +----------+ +----------+ +----------+
| | | Log | | Log | | User | | Remote |
| Console | | Buffer | | File(s) | | Terminals| | Servers|
+----------+ +----------+ +----------+ +----------+ +----------+
The leaves in the base syslog model correspond to the group level
suppression filter and each message distributor:
- console
- log buffer
- log file(s)
- user terminals
- remote server(s).
Optional features are used to specified fields that are not present in
all vendor configurations.
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3.1. SYSLOG Module
module: ietf-syslog
+--rw syslog
+--rw global-logging-action {global-logging-action}?
| +--rw (logging-level-scope)?
| | +--:(logging-facility-all)
| | | +--rw severity? syslogtypes:severity
| | +--:(logging-facility-none)
| | | +--rw none? empty
| | +--:(logging-facility)
| | +--rw logging-facilities* [facility]
| | +--rw facility identityref
| | +--rw severity? syslogtypes:severity
| +--rw logging-advanced-level-processing {selector-advanced-level-processing-config}?
| | +--rw select-message-severity? enumeration
| +--rw logging-match-processing {selector-match-processing-config}?
| +--rw pattern-match? string
+--rw console-logging-action
| +--rw (logging-level-scope)?
| | +--:(logging-facility-all)
| | | +--rw severity? syslogtypes:severity
| | +--:(logging-facility-none)
| | | +--rw none? empty
| | +--:(logging-facility)
| | +--rw logging-facilities* [facility]
| | +--rw facility identityref
| | +--rw severity? syslogtypes:severity
| +--rw logging-advanced-level-processing {selector-advanced-level-processing-config}?
| | +--rw select-message-severity? enumeration
| +--rw logging-match-processing {selector-match-processing-config}?
| +--rw pattern-match? string
+--rw buffered-logging-action
| +--rw (logging-level-scope)?
| | +--:(logging-facility-all)
| | | +--rw severity? syslogtypes:severity
| | +--:(logging-facility-none)
| | | +--rw none? empty
| | +--:(logging-facility)
| | +--rw logging-facilities* [facility]
| | +--rw facility identityref
| | +--rw severity? syslogtypes:severity
| +--rw logging-advanced-level-processing {selector-advanced-level-processing-config}?
| | +--rw select-message-severity? enumeration
| +--rw logging-match-processing {selector-match-processing-config}?
| | +--rw pattern-match? string
| +--rw buffer-size? uint64
+--rw file-logging-action
| +--rw logging-files* [file-name]
| +--rw file-name inet:uri
| +--rw (logging-level-scope)?
| | +--:(logging-facility-all)
| | | +--rw severity? syslogtypes:severity
| | +--:(logging-facility-none)
| | | +--rw none? empty
| | +--:(logging-facility)
| | +--rw logging-facilities* [facility]
| | +--rw facility identityref
| | +--rw severity? syslogtypes:severity
| +--rw logging-advanced-level-processing {selector-advanced-level-processing-config}?
| | +--rw select-message-severity? enumeration
| +--rw logging-match-processing {selector-match-processing-config}?
| | +--rw pattern-match? string
| +--rw file-logging-structured-data? boolean {file-logging-structured-data}?
| +--rw file-logging-archive {file-logging-archive-config}?
| +--rw file-number? uint32
| +--rw file-size? uint64
| +--rw file-permission? enumeration
+--rw remote-logging-action
| +--rw remote-logging-destination* [destination]
| +--rw destination inet:host
| +--rw (logging-level-scope)?
| | +--:(logging-facility-all)
| | | +--rw severity? syslogtypes:severity
| | +--:(logging-facility-none)
| | | +--rw none? empty
| | +--:(logging-facility)
| | +--rw logging-facilities* [facility]
| | +--rw facility identityref
| | +--rw severity? syslogtypes:severity
| +--rw logging-advanced-level-processing {selector-advanced-level-processing-config}?
| | +--rw select-message-severity? enumeration
| +--rw logging-match-processing {selector-match-processing-config}?
| | +--rw pattern-match? string
| +--rw remote-logging-structured-data? boolean {remote-logging-structured-data}?
| +--rw destination-port? inet:port-number
| +--rw destination-facility? identityref
| +--rw source-interface? if:interface-ref
| +--rw vrf-name? string {remote-logging-use-vrf}?
| +--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-logging-action
+--rw (user-scope)?
+--:(all-users)
| +--rw all-users
| +--rw (logging-level-scope)?
| | +--:(logging-facility-all)
| | | +--rw severity? syslogtypes:severity
| | +--:(logging-facility-none)
| | | +--rw none? empty
| | +--:(logging-facility)
| | +--rw logging-facilities* [facility]
| | +--rw facility identityref
| | +--rw severity? syslogtypes:severity
| +--rw logging-advanced-level-processing {selector-advanced-level-processing-config}?
| | +--rw select-message-severity? enumeration
| +--rw logging-match-processing {selector-match-processing-config}?
| +--rw pattern-match? string
+--:(per-user) {terminal-facility-user-logging-config}?
+--rw user-name* [uname]
+--rw uname string
+--rw (logging-level-scope)?
| +--:(logging-facility-all)
| | +--rw severity? syslogtypes:severity
| +--:(logging-facility-none)
| | +--rw none? empty
| +--:(logging-facility)
| +--rw logging-facilities* [facility]
| +--rw facility identityref
| +--rw severity? syslogtypes:severity
+--rw logging-advanced-level-processing {selector-advanced-level-processing-config}?
| +--rw select-message-severity? enumeration
+--rw logging-match-processing {selector-match-processing-config}?
+--rw pattern-match? string
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4. SYSLOG YANG Models
4.1. SYSLOG-TYPES module
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:
WG List:
WG Chair: Juergen Schoenwaelder
WG Chair: Tom Nadeau
Editor: Clyde Wildes
Editor: Agrahara Kiran Koushik
";
description
"This module contains a collection of YANG type definitions for
SYSLOG.";
revision 2015-03-05 {
description
"Initial Revision";
reference
"This model references RFC 5424 - The Syslog Protocol.";
}
typedef severity {
type enumeration {
enum "emergency" {
value 0;
description
"Emergency Level Msg";
}
enum "alert" {
value 1;
description
"Alert Level Msg";
}
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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;
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.";
}
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.";
}
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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.";
}
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.";
}
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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.";
}
}
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4.2. SYSLOG module
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:
WG List:
WG Chair: David Kessens
WG Chair: Juergen Schoenwaelder
Editor: Clyde Wildes
Editor: Agrahara Kiran Koushik
";
description
"This module contains a collection of YANG definitions
for Syslog configuration.";
revision 2015-03-05 {
description
"Initial Revision";
reference
"This model references RFC 5424 - The Syslog Protocol,
and RFC 5848 - Signed Syslog Messages.";
}
feature global-logging-action {
description
"This feature represents the ability to suppress log
messages on the global level.";
}
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feature file-logging-structured-data {
description
"This feature represents the ability to log messages
to a file in structured-data format as per RFC 5424.";
}
feature remote-logging-structured-data {
description
"This feature represents the ability to deliver log
messages to a remote server in structured-data format
as per RFC 5424.";
}
feature file-logging-archive-config {
description
"This feature represents the ability to archive log files.";
}
feature remote-logging-use-vrf {
description
"This feature allows remote logging of messages to a
particular VRF.";
}
feature terminal-facility-user-logging-config {
description
"This feature represents the ability to adjust
log message settings for individual terminal users.";
}
feature selector-advanced-level-processing-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
filter log messages.";
leaf severity {
type syslogtypes:severity;
description
"This leaf specifies the Syslog message severity.
No value implies all severities.";
}
}
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grouping syslog-selector {
description
"This grouping defines a Syslog selector which is used to
filter log messages for the given action in which the
selector appears. Choose one of the following:
logging-facility-all
logging-facility-none
logging-facility [ ...]
Additional severity comparison operations are available
using the logging-advanced-level-processing container. If
the logging-advanced-level-processing container is not
present all messages of the specified severity and higher
are logged according to the given action.";
choice logging-level-scope {
default logging-facility-all;
description
"This choice describes the option to specify all
facilities, no facilities, or a specific facility.";
case logging-facility-all {
description
"This case specifies all facilities will match when
comparing the Syslog message facility.";
uses syslog-severity;
}
case logging-facility-none {
description
"This case specifies no facilities will match when
comparing the Syslog message facility. This is a method
that can be used to turn an action off.";
leaf none {
type empty;
description
"This leaf specifies that no facilities participate in the
filtering of Syslog messages for this action.";
}
}
case logging-facility {
description
"This case specifies one or more specified facilities
will match when comparing the Syslog message facility.";
list logging-facilities {
key "facility";
description
"This list describes a collection of Syslog facilities
and severities.";
leaf facility {
type identityref {
base syslogtypes:syslog-facility;
}
description
"The leaf uniquely identifies a Syslog facility.";
}
uses syslog-severity;
}
}
}
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container logging-advanced-level-processing {
if-feature selector-advanced-level-processing-config;
description
"This container describes the configuration parameters for
advanced Syslog selector severity comparison.";
leaf select-message-severity {
type enumeration {
enum equals-or-higher {
description
"All messages of the specified severity and higher are
logged according to the given action";
}
enum equals {
description
"This leaf specifies all messages for the specified
severity.";
}
enum not-equals {
description
"This leaf specifies all messages that are not for the
specified severity.";
}
}
default equals-or-higher;
description
"This leaf describes the option to specify how the
severity comparison is performed.";
}
}
container logging-match-processing {
if-feature selector-match-processing-config;
description
"This container describes the configuration parameters for
matching Syslog messages using a regular expression pattern
match.";
leaf pattern-match {
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 global-logging-action {
if-feature global-logging-action;
description
"This container describes the configuration parameters for
global logging. Global logging represents the ability to
perform global log message suppression.";
uses syslog-selector;
}
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container console-logging-action {
description
"This container describes the configuration parameters for
console logging.";
uses syslog-selector;
}
container buffered-logging-action {
description
"This container describes the configuration parameters for
local memory buffer logging.";
uses syslog-selector;
leaf buffer-size {
type uint64;
description
"This leaf describes the amount of memory that will be
dedicated to local memory buffer logging. The default
value varies by implementation.";
}
}
container file-logging-action {
description
"This container describes the configuration parameters for
file logging.";
list logging-files {
key "file-name";
description
"This list describes a collection of local logging
files.";
leaf file-name {
type inet:uri;
description
"This leaf specifies the name of the log file.";
}
uses syslog-selector;
leaf file-logging-structured-data {
if-feature file-logging-structured-data;
type boolean;
default false;
description
"This leaf describes how log messages are written to the
log file. If true, messages will be written in
structured-data format; if false, messages will be
written in standard message format.";
}
container file-logging-archive {
if-feature file-logging-archive-config;
description
"This container describes the configuration parameters
for log file archiving.";
leaf file-number {
type uint32;
default 1;
description
"This leaf specifies the maximum number of log files
retained.";
}
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leaf file-size {
type uint64;
default 262144;
description
"This leaf specifies the maximum log file size.";
}
leaf file-permission {
type enumeration {
enum world-readable {
value 1;
description
"This enum specifies that the log files
are readable by world.";
}
enum no-world-readable {
value 2;
description
"This enum specifies that the log files
are not readable by world.";
}
}
default no-world-readable;
description
"This leaf describes who can read log files";
}
}
}
}
container remote-logging-action {
description
"This container describes the configuration parameters for
remote logging.";
list remote-logging-destination {
key "destination";
description
"This list describes a collection of remote logging
destinations.";
leaf destination {
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.";
}
uses syslog-selector;
leaf remote-logging-structured-data {
if-feature remote-logging-structured-data;
type boolean;
default false;
description
"This leaf describes how log messages are sent to the
remote server. If true, messages will be sent in
structured-data format; if false, messages will be
sent in standard message format.";
}
leaf destination-port {
type inet:port-number;
default 514;
description
"This leaf specifies the port number used to deliver
messages to the remote server.";
}
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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";
}
leaf vrf-name {
if-feature remote-logging-use-vrf;
type string;
description
"This leaf specifies the name of the virtual routing
facility (VRF) that connects to the syslog server
host. If not set, the default VRF will be used.";
}
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.";
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.";
}
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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-logging-action {
description
"This container describes the configuration parameters for
the terminal logging configuration.";
choice user-scope {
default all-users;
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 terminals";
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 terminal-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.";
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leaf uname {
type string;
description
"This leaf uniquely describes a user name which is
the login name of the user whose terminal session
is to receive log messages.";
}
uses syslog-selector;
}
}
}
}
}
}
4.3. A SYSLOG Example
Requirement:
Enable global logging of two facilities:
kern - severity critical(1)
auth - severity error(3)
Enable console logging of syslogs of severity
critical(1)
Here is the example syslog configuration xml:
syslogtypes:kernsyslogtypes:critical
syslogtypes:authsyslogtypes:error
syslogtypes:critical
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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:global-logging-action logging level cron 2
syslog:console-logging-action logging console 1
syslog:file-logging-action logging logfile mylog.log 2 4096
syslog:terminal-logging-action logging monitor 2
syslog:remote-logging-action *logging server server.cisco.com 2
facility user
use-vrf management
*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., )
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.
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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 version 00 of this proposal:
Jim Gibson
Jeffrey Haas
John Heasley
Giles Heron
Lisa Huang
Jeffrey K Lange
Chris Lonvick
Juergen Schoenwaelder
Peter Van Horne
Bert Wijnen
Aleksandr Zhdankin
9. Change log [RFC Editor: Please remove]
10. References
[RFC3164] Lonvick, C., "The BSD syslog Protocol", BCP 81, RFC 3164,
August 2001.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
March 2204.
[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.
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[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
Brocade Communications Systems
Email: kkoushik@brocade.com
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