Jacobs University Bremen
A. Clemm
Cisco Systems
A. Karmakar
Cisco Systems India Pvt Ltd
October 2009
Definitions of Managed Objects for Mapping SYSLOG Messages to
Simple Network Management Protocol (SNMP) Notifications
Abstract
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This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it defines a mapping of SYSLOG messages to Simple Network Management Protocol (SNMP) notifications.
Status of This Memo
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This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
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Copyright © 2009 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 BSD License.
Table of Contents
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1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2 2. The Internet-Standard Management Framework . . . . . . . . . . 2 3. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 5. Relationship to Other MIB Modules . . . . . . . . . . . . . . 4 6. Relationship to the SNMP Notification to SYSLOG Mapping . . . 6 7. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . 5 8. Usage Example . . . . . . . . . . . . . . . . . . . . . . . . 18 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18 10. Security Considerations . . . . . . . . . . . . . . . . . . . 19 11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 20 12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 20 12.1. Normative References . . . . . . . . . . . . . . . . . . 20 12.2. Informative References . . . . . . . . . . . . . . . . . 21
1. Introduction
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SNMP ([RFC3410], [RFC3411]) and SYSLOG [RFC5424] are two widely used protocols to communicate event notifications. Although co-existence of several management protocols in one operational environment is possible, certain environments require that all event notifications be collected by a single system daemon, such as a SYSLOG collector or an SNMP notification receiver, via a single management protocol. In such environments, it is necessary to translate event notifications between management protocols.
This document defines an SNMP MIB module to represent SYSLOG messages and to send SYSLOG messages as SNMP notifications to SNMP notification receivers.
2. The Internet-Standard Management Framework
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For a detailed overview of the documents that describe the current Internet-Standard Management Framework, please refer to section 7 of RFC 3410 [RFC3410].
Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. MIB objects are generally accessed through the Simple Network Management Protocol (SNMP). Objects in the MIB are defined using the mechanisms defined in the Structure of Management Information (SMI). This memo specifies a MIB module that is compliant to the SMIv2, which is described in STD 58, RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580 [RFC2580].
3. Conventions
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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 [RFC2119].
4. Overview
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SYSLOG messages are translated to SNMP by a SYSLOG-to-SNMP translator. Such a translator acts as a SYSLOG collector [RFC5424] and implements a MIB module according to the SNMP architecture [RFC3411]. The translator might be tightly coupled to an SNMP agent or it might interface with an SNMP agent via a subagent protocol.
After initialization, the SYSLOG-to-SNMP translator will listen for SYSLOG messages. On receiving a message, the message will be parsed to extract information as described in the MIB module. A conceptual table is populated with information extracted from the SYSLOG message, and finally a notification may be generated.
The MIB module is organized into a group of scalars and two tables. The syslogMsgControl group contains two scalars controlling the maximum size of SYSLOG messages recorded in the tables and also controlling whether SNMP notifications are generated for SYSLOG messages.
--syslogMsgObjects(1)
| +--syslogMsgControl(1) | +-- Unsigned32 syslogMsgTableMaxSize(1) +-- TruthValue syslogMsgEnableNotifications(2)The syslogMsgTable contains one entry for each recorded SYSLOG message. The basic fields of SYSLOG messages as well as message properties are represented in different columns of the conceptual table.
--syslogMsgObjects(1)
| +--syslogMsgTable(2) | +--syslogMsgEntry(1) [syslogMsgIndex] | +-- Unsigned32 syslogMsgIndex(1) +-- SyslogFacility syslogMsgFacility(2) +-- SyslogSeverity syslogMsgSeverity(3) +-- Unsigned32 syslogMsgVersion(4) +-- SyslogTimeStamp syslogMsgTimeStamp(5) +-- DisplayString syslogMsgHostName(6) +-- DisplayString syslogMsgAppName(7) +-- DisplayString syslogMsgProcID(8) +-- DisplayString syslogMsgMsgID(9) +-- Unsigned32 syslogMsgSDParams(10) +-- OctetString syslogMsgMsg(11)The syslogMsgSDTable contains one entry for each structured data element parameter contained in a SYSLOG message. Since structured data elements are optional, the relationship between the syslogMsgTable and the syslogMsgSDTable ranges from one-to-zero to one-to-many.
--syslogMsgObjects(1)
| +--syslogMsgSDTable(3) | +--syslogMsgSDEntry(1) [syslogMsgIndex, | syslogMsgSDParamIndex, | syslogMsgSDID, | syslogMsgSDParamName] | +-- Unsigned32 syslogMsgSDParamIndex(1) +-- DisplayString syslogMsgSDID(2) +-- DisplayString syslogMsgSDParamName(3) +-- SyslogParamValueString syslogMsgSDParamValue(4)
5. Relationship to Other MIB Modules
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The NOTIFICATION-LOG-MIB [RFC3014] provides a generic mechanism for logging SNMP notifications in order to deal with lost SNMP notifications, e.g., due to transient communication problems. Applications can poll the notification log to verify that they have not missed important SNMP notifications.
The MIB module defined in this memo provides a mechanism for logging SYSLOG notifications. This additional SYSLOG notification log is provided because (a) SYSLOG messages might not lead to SNMP notification (this is configurable) and (b) SNMP notifications might not carry all information associated with a SYSLOG notification.
The MIB module IMPORTS objects from SNMPv2-SMI [RFC2578], SNMPv2-TC [RFC2579], SNMPv2-CONF [RFC2580], SNMP-FRAMEWORK-MIB [RFC3411], and SYSLOG-TC-MIB [RFC5427].
The textual convention SyslogParamValueString uses the UTF-8 transformation format of the ISO/IEC IS 10646-1 character set defined in [RFC3629].
6. Relationship to the SNMP Notification to SYSLOG Mapping
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A companion document [RFC5675] defines a mapping of SNMP notifications to SYSLOG messages. This section discusses the possibilities of using both specifications in combination.
A SYSLOG collector implementing the SYSLOG-MSG-MIB module and the mapping of SNMP notifications to SYSLOG messages may be configured to translate received SYSLOG messages containing SNMP notifications back into the original SNMP notification. In this case, the relevant tables of the SYSLOG-MSG-MIB will not be populated for SYSLOG messages carrying SNMP notifications. This configuration allows operators to build a forwarding chain where SNMP notifications are "tunneled" through SYSLOG messages. Due to size restrictions of the SYSLOG transports and the more verbose textual encoding used by SYSLOG, there is a possibility that SNMP notification content will get truncated when tunneled through SYSLOG, and thus the resulting SNMP notification may be incomplete.
An SNMP management application supporting the SYSLOG-MSG-MIB and the mapping of SNMP notifications to SYSLOG messages may process information from the SYSLOG-MSG-MIB in order to emit a SYSLOG message representing the SYSLOG message recorded in the SYSLOG-MSG-MIB module. This configuration allows operators to build a forwarding chain where SYSLOG messages are "tunneled" through SNMP messages. A notification receiver can determine whether a syslogMsgNotification contained all structured data element parameters of a SYSLOG message. In case parameters are missing, a forwarding application MUST retrieve the missing parameters from the SYSLOG-MSG-MIB. Regular polling of the SYSLOG-MSG-MIB can be used to take care of any lost SNMP notifications.
7. Definitions
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SYSLOG-MSG-MIB DEFINITIONS ::= BEGIN
IMPORTS
MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE, Unsigned32, mib-2 FROM SNMPv2-SMI TEXTUAL-CONVENTION, DisplayString, TruthValue FROM SNMPv2-TC OBJECT-GROUP, NOTIFICATION-GROUP, MODULE-COMPLIANCE FROM SNMPv2-CONF SyslogFacility, SyslogSeverity FROM SYSLOG-TC-MIB;syslogMsgMib MODULE-IDENTITY
LAST-UPDATED "200908130800Z" ORGANIZATION "IETF OPSAWG Working Group" CONTACT-INFO "Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de> Jacobs University Bremen Campus Ring 1 28757 Bremen Germany-
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Alexander Clemm
<alex@cisco.com>
Cisco Systems
170 West Tasman Drive
San Jose, CA 95134-1706
USAAnirban Karmakar
<akarmaka@cisco.com>
Cisco Systems India Pvt Ltd
SEZ Unit, Cessna Business Park,
Sarjapur Marathahalli ORR,
Bangalore, Karnataka 560103
India"
DESCRIPTION
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"This MIB module represents SYSLOG messages as SNMP objects.
Copyright © 2009 IETF Trust and the persons identified as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or without modification, is permitted pursuant to, and subject to the license terms contained in, the Simplified BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info).
This version of this MIB module is part of RFC 5676; see the RFC itself for full legal notices."
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REVISION "200908130800Z" DESCRIPTION "Initial version issued as part of RFC 5676." ::= { mib-2 192 }-- textual convention definitions
SyslogTimeStamp ::= TEXTUAL-CONVENTION
DISPLAY-HINT "2d-1d-1d,1d:1d:1d.3d,1a1d:1d" STATUS current DESCRIPTION "A date-time specification. This type is similar to the DateAndTime type defined in the SNMPv2-TC, except the subsecond granulation is microseconds instead of deciseconds and a zero-length string can be used to indicate a missing value. field octets contents range ----- ------ -------- ----- 1 1-2 year* 0..65536 2 3 month 1..12 3 4 day 1..31 4 5 hour 0..23 5 6 minutes 0..59 6 7 seconds 0..60 (use 60 for leap-second) 7 8-10 microseconds* 0..999999 8 11 direction from UTC '+' / '-' 9 12 hours from UTC* 0..13 10 13 minutes from UTC 0..59-
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* Notes:
- the value of year is in network-byte order
- the value of microseconds is in network-byte order - daylight saving time in New Zealand is +13For example, Tuesday May 26, 1992 at 1:30:15 PM EDT would be displayed as:
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1992-5-26,13:30:15.0,-4:0
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Note that if only local time is known, then timezone information (fields 11-13) is not present." SYNTAX OCTET STRING (SIZE (0 | 10 | 13))SyslogParamValueString ::= TEXTUAL-CONVENTION
DISPLAY-HINT "65535t" STATUS current DESCRIPTION "The value of a SYSLOG SD-PARAM is represented using the ISO/IEC IS 10646-1 character set, encoded as an octet string using the UTF-8 transformation format described in RFC 3629.-
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Since additional code points are added by amendments to the 10646 standard from time to time, implementations must be prepared to encounter any code point from 0x00000000 to 0x7fffffff. Byte sequences that do not correspond to the valid UTF-8 encoding of a code point or that are outside this range are prohibited. Similarly, overlong UTF-8 sequences are prohibited.
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UTF-8 may require multiple bytes to represent a single character / code point; thus, the length of this object in octets may be different from the number of characters encoded. Similarly, size constraints refer to the number of encoded octets, not the number of characters represented by an encoding." REFERENCE "RFC 3629: UTF-8, a transformation format of ISO 10646" SYNTAX OCTET STRING -- object definitions syslogMsgNotifications OBJECT IDENTIFIER ::= { syslogMsgMib 0 } syslogMsgObjects OBJECT IDENTIFIER ::= { syslogMsgMib 1 } syslogMsgConformance OBJECT IDENTIFIER ::= { syslogMsgMib 2 } syslogMsgControl OBJECT IDENTIFIER ::= { syslogMsgObjects 1 }syslogMsgTableMaxSize OBJECT-TYPE
SYNTAX Unsigned32 MAX-ACCESS read-write STATUS current DESCRIPTION "The maximum number of SYSLOG messages that may be held in syslogMsgTable. A particular setting does not guarantee that there is sufficient memory available for the maximum number of table entries indicated by this object. A value of 0 means no fixed limit.-
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If an application reduces the limit while there are SYSLOG messages in the syslogMsgTable, the SYSLOG messages that are in the syslogMsgTable for the longest time MUST be discarded to bring the table down to the new limit.
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The value of this object should be kept in nonvolatile memory." DEFVAL { 0 } ::= { syslogMsgControl 1 } syslogMsgEnableNotifications OBJECT-TYPE SYNTAX TruthValue MAX-ACCESS read-write STATUS current DESCRIPTION "Indicates whether syslogMsgNotification notifications are generated. The value of this object should be kept in nonvolatile memory." DEFVAL { false } ::= { syslogMsgControl 2 }syslogMsgTable OBJECT-TYPE
SYNTAX SEQUENCE OF SyslogMsgEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "A table containing recent SYSLOG messages. The size of the table is controlled by the syslogMsgTableMaxSize object." ::= { syslogMsgObjects 2 }syslogMsgEntry OBJECT-TYPE
SYNTAX SyslogMsgEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry of the syslogMsgTable." INDEX { syslogMsgIndex } ::= { syslogMsgTable 1 } SyslogMsgEntry ::= SEQUENCE { syslogMsgIndex Unsigned32, syslogMsgFacility SyslogFacility, syslogMsgSeverity SyslogSeverity, syslogMsgVersion Unsigned32, syslogMsgTimeStamp SyslogTimeStamp, syslogMsgHostName DisplayString, syslogMsgAppName DisplayString, syslogMsgProcID DisplayString, syslogMsgMsgID DisplayString, syslogMsgSDParams Unsigned32, syslogMsgMsg OCTET STRING }syslogMsgIndex OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295) MAX-ACCESS not-accessible STATUS current-
DESCRIPTION
"A monotonically increasing number used to identify entries in
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the syslogMsgTable. When syslogMsgIndex reaches the maximum value (4294967295), the value wraps back to 1.
Applications periodically polling the syslogMsgTable for new entries should take into account that a complete rollover of syslogMsgIndex will happen if more than 4294967294 messages are received during a poll interval." ::= { syslogMsgEntry 1 }syslogMsgFacility OBJECT-TYPE
SYNTAX SyslogFacility MAX-ACCESS read-only STATUS current DESCRIPTION "The facility of the SYSLOG message." REFERENCE "RFC 5424: The Syslog Protocol (Section 6.2.1) RFC 5427: Textual Conventions for Syslog Management" ::= { syslogMsgEntry 2 }syslogMsgSeverity OBJECT-TYPE
SYNTAX SyslogSeverity MAX-ACCESS read-only STATUS current DESCRIPTION "The severity of the SYSLOG message" REFERENCE "RFC 5424: The Syslog Protocol (Section 6.2.1) RFC 5427: Textual Conventions for Syslog Management" ::= { syslogMsgEntry 3 }syslogMsgVersion OBJECT-TYPE
SYNTAX Unsigned32 (0..999) MAX-ACCESS read-only STATUS current DESCRIPTION "The version of the SYSLOG message. A value of 0 indicates that the version is unknown." REFERENCE "RFC 5424: The Syslog Protocol (Section 6.2.2)" ::= { syslogMsgEntry 4 }syslogMsgTimeStamp OBJECT-TYPE
SYNTAX SyslogTimeStamp MAX-ACCESS read-only STATUS current DESCRIPTION "The timestamp of the SYSLOG message. A zero-length string is returned if the timestamp is unknown." REFERENCE "RFC 5424: The Syslog Protocol (Section 6.2.3)" ::= { syslogMsgEntry 5 }syslogMsgHostName OBJECT-TYPE
SYNTAX DisplayString (SIZE (0..255)) MAX-ACCESS read-only STATUS current DESCRIPTION "The hostname and the (optional) domain name of the SYSLOG message. A zero-length string indicates an unknown hostname. The SYSLOG protocol specification constrains this string to printable US-ASCII code points." REFERENCE "RFC 5424: The Syslog Protocol (Section 6.2.4)" ::= { syslogMsgEntry 6 }syslogMsgAppName OBJECT-TYPE
SYNTAX DisplayString (SIZE (0..48)) MAX-ACCESS read-only STATUS current DESCRIPTION "The app-name of the SYSLOG message. A zero-length string indicates an unknown app-name. The SYSLOG protocol specification constrains this string to printable US-ASCII code points." REFERENCE "RFC 5424: The Syslog Protocol (Section 6.2.5)" ::= { syslogMsgEntry 7 }syslogMsgProcID OBJECT-TYPE
SYNTAX DisplayString (SIZE (0..128)) MAX-ACCESS read-only STATUS current DESCRIPTION "The procid of the SYSLOG message. A zero-length string indicates an unknown procid. The SYSLOG protocol specification constrains this string to printable US-ASCII code points." REFERENCE "RFC 5424: The Syslog Protocol (Section 6.2.6)" ::= { syslogMsgEntry 8 }syslogMsgMsgID OBJECT-TYPE
SYNTAX DisplayString (SIZE (0..32)) MAX-ACCESS read-only STATUS current DESCRIPTION "The msgid of the SYSLOG message. A zero-length string indicates an unknown msgid. The SYSLOG protocol specification constrains this string to printable US-ASCII code points." REFERENCE "RFC 5424: The Syslog Protocol (Section 6.2.7)" ::= { syslogMsgEntry 9 }syslogMsgSDParams OBJECT-TYPE
SYNTAX Unsigned32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of structured data element parameters carried in the SYSLOG message. This number effectively indicates the number of entries in the syslogMsgSDTable. It can be used, for example, by a notification receiver to determine whether a notification carried all structured data element parameters of a SYSLOG message." ::= { syslogMsgEntry 10 }syslogMsgMsg OBJECT-TYPE
SYNTAX OCTET STRING MAX-ACCESS read-only STATUS current DESCRIPTION "The message part of the SYSLOG message. The syntax does not impose a size restriction. Implementations of this MIB module may truncate the message part of the SYSLOG message such that it fits into the size constraints imposed by the implementation environment. Such truncations can also happen elsewhere in the SYSLOG forwarding chain. If the first octets contain the value 'EFBBBF'h, then the rest of the message is a UTF-8 string. Since SYSLOG messages may be truncated at arbitrary octet boundaries during forwarding, the message may contain invalid UTF-8 encodings at the end." REFERENCE "RFC 5424: The Syslog Protocol (Sections 6.1 and 6.4)" ::= { syslogMsgEntry 11 }syslogMsgSDTable OBJECT-TYPE
SYNTAX SEQUENCE OF SyslogMsgSDEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "A table containing structured data elements of SYSLOG messages." ::= { syslogMsgObjects 3 }syslogMsgSDEntry OBJECT-TYPE
SYNTAX SyslogMsgSDEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry of the syslogMsgSDTable." INDEX { syslogMsgIndex, syslogMsgSDParamIndex, syslogMsgSDID, syslogMsgSDParamName } ::= { syslogMsgSDTable 1 } SyslogMsgSDEntry ::= SEQUENCE { syslogMsgSDParamIndex Unsigned32, syslogMsgSDID DisplayString, syslogMsgSDParamName DisplayString, syslogMsgSDParamValue SyslogParamValueString }syslogMsgSDParamIndex OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295) MAX-ACCESS not-accessible STATUS current DESCRIPTION "This object indexes the structured data element parameters contained in a SYSLOG message. The first structured data element parameter has the index value 1, and subsequent parameters are indexed by incrementing the index of the previous parameter. The index increases across structured data element boundaries so that the value reflects the position of a structured data element parameter in a SYSLOG message." REFERENCE "RFC 5424: The Syslog Protocol (Section 6.3.3)" ::= { syslogMsgSDEntry 1 }syslogMsgSDID OBJECT-TYPE
SYNTAX DisplayString (SIZE (1..32)) MAX-ACCESS not-accessible STATUS current DESCRIPTION "The name (SD-ID) of a structured data element. The SYSLOG protocol specification constrains this string to printable US-ASCII code points." REFERENCE "RFC 5424: The Syslog Protocol (Section 6.3.2)" ::= { syslogMsgSDEntry 2 }syslogMsgSDParamName OBJECT-TYPE
SYNTAX DisplayString (SIZE (1..32)) MAX-ACCESS not-accessible STATUS current DESCRIPTION "The name of a parameter of the structured data element. The SYSLOG protocol specification constrains this string to printable US-ASCII code points." REFERENCE "RFC 5424: The Syslog Protocol (Section 6.3.3)" ::= { syslogMsgSDEntry 3 }syslogMsgSDParamValue OBJECT-TYPE
SYNTAX SyslogParamValueString MAX-ACCESS read-only STATUS current DESCRIPTION "The value of the parameter of a SYSLOG message identified by the index of this table. The value is stored in the unescaped format." REFERENCE "RFC 5424: The Syslog Protocol (Section 6.3.3)" ::= { syslogMsgSDEntry 4 } -- notification definitionssyslogMsgNotification NOTIFICATION-TYPE
OBJECTS { syslogMsgFacility, syslogMsgSeverity, syslogMsgVersion, syslogMsgTimeStamp, syslogMsgHostName, syslogMsgAppName, syslogMsgProcID, syslogMsgMsgID, syslogMsgSDParams, syslogMsgMsg } STATUS current DESCRIPTION "The syslogMsgNotification is generated when a new SYSLOG message is received and the value of syslogMsgGenerateNotifications is true. Implementations may add syslogMsgSDParamValue objects as long as the resulting notification fits into the size constraints imposed by the implementation environment and the notification message size constraints imposed by maxMessageSize [RFC3412] and SNMP transport mappings." ::= { syslogMsgNotifications 1 } -- conformance statements syslogMsgGroups OBJECT IDENTIFIER ::= { syslogMsgConformance 1 } syslogMsgCompliances OBJECT IDENTIFIER ::= { syslogMsgConformance 2 }syslogMsgFullCompliance MODULE-COMPLIANCE
STATUS current DESCRIPTION "The compliance statement for implementations of the SYSLOG-MSG-MIB." MODULE -- this module MANDATORY-GROUPS { syslogMsgGroup, syslogMsgSDGroup, syslogMsgControlGroup, syslogMsgNotificationGroup } ::= { syslogMsgCompliances 1 }syslogMsgReadOnlyCompliance MODULE-COMPLIANCE
STATUS current DESCRIPTION "The compliance statement for implementations of the SYSLOG-MSG-MIB that do not support read-write access." MODULE -- this module MANDATORY-GROUPS { syslogMsgGroup, syslogMsgSDGroup, syslogMsgControlGroup, syslogMsgNotificationGroup } OBJECT syslogMsgTableMaxSize MIN-ACCESS read-only DESCRIPTION "Write access is not required." OBJECT syslogMsgEnableNotifications MIN-ACCESS read-only DESCRIPTION "Write access is not required." ::= { syslogMsgCompliances 2 }syslogMsgNotificationCompliance MODULE-COMPLIANCE
STATUS current DESCRIPTION "The compliance statement for implementations of the SYSLOG-MSG-MIB that do only generate notifications and do not provide a table to allow read access to SYSLOG message details." MODULE -- this module MANDATORY-GROUPS { syslogMsgGroup, syslogMsgSDGroup, syslogMsgNotificationGroup } OBJECT syslogMsgFacility MIN-ACCESS accessible-for-notify DESCRIPTION "Read access is not required." OBJECT syslogMsgSeverity MIN-ACCESS accessible-for-notify DESCRIPTION "Read access is not required." OBJECT syslogMsgVersion MIN-ACCESS accessible-for-notify DESCRIPTION "Read access is not required." OBJECT syslogMsgTimeStamp MIN-ACCESS accessible-for-notify DESCRIPTION "Read access is not required." OBJECT syslogMsgHostName MIN-ACCESS accessible-for-notify DESCRIPTION "Read access is not required." OBJECT syslogMsgAppName MIN-ACCESS accessible-for-notify DESCRIPTION "Read access is not required." OBJECT syslogMsgProcID MIN-ACCESS accessible-for-notify DESCRIPTION "Read access is not required." OBJECT syslogMsgMsgID MIN-ACCESS accessible-for-notify DESCRIPTION "Read access is not required." OBJECT syslogMsgSDParams MIN-ACCESS accessible-for-notify DESCRIPTION "Read access is not required." OBJECT syslogMsgMsg MIN-ACCESS accessible-for-notify DESCRIPTION "Read access is not required." OBJECT syslogMsgSDParamValue MIN-ACCESS accessible-for-notify DESCRIPTION "Read access is not required." ::= { syslogMsgCompliances 3 }syslogMsgNotificationGroup NOTIFICATION-GROUP
NOTIFICATIONS { syslogMsgNotification } STATUS current DESCRIPTION "The notifications emitted by this MIB module." ::= { syslogMsgGroups 1 }syslogMsgGroup OBJECT-GROUP
OBJECTS { -- syslogMsgIndex, syslogMsgFacility, syslogMsgSeverity, syslogMsgVersion, syslogMsgTimeStamp, syslogMsgHostName, syslogMsgAppName, syslogMsgProcID, syslogMsgMsgID, syslogMsgSDParams, syslogMsgMsg } STATUS current DESCRIPTION "A collection of objects representing a SYSLOG message, excluding structured data elements." ::= { syslogMsgGroups 2 }syslogMsgSDGroup OBJECT-GROUP
OBJECTS { -- syslogMsgSDParamIndex, -- syslogMsgSDID, -- syslogMsgSDParamName, syslogMsgSDParamValue } STATUS current DESCRIPTION "A collection of objects representing the structured data elements of a SYSLOG message." ::= { syslogMsgGroups 3 }syslogMsgControlGroup OBJECT-GROUP
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OBJECTS {
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syslogMsgTableMaxSize,
syslogMsgEnableNotifications
} STATUS current DESCRIPTION "A collection of control objects to control the size of the syslogMsgTable and to enable/disable notifications." ::= { syslogMsgGroups 4 } END
8. Usage Example
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The following example shows a valid SYSLOG message including structured data. The otherwise-unprintable Unicode byte order mark (BOM) is represented as "BOM" in the example.
<165>1 2003-10-11T22:14:15.003Z mymachine.example.com evntslog - ID47 [exampleSDID@32473 iut="3" eventSource="Application" eventID="1011"] BOMAn application event log entry...This SYSLOG message leads to the following entries in the syslogMsgTable and the syslogMsgSDTable (note that string indexes are written as strings for readability reasons):
syslogMsgIndex.1 = 1 syslogMsgFacility.1 = 20 syslogMsgSeverity.1 = 5 syslogMsgVersion.1 = 1 syslogMsgTimeStamp.1 = 2003-10-11,22:14:15.003,+0:0 syslogMsgHostName.1 = "mymachine.example.com" syslogMsgAppName.1 = "evntslog" syslogMsgProcID.1 = "-" syslogMsgMsgID.1 = "ID47" syslogMsgMsg.1 = "BOMAn application event log entry..." syslogMsgSDParamValue.1.1."exampleSDID@32473"."iut" = "3" syslogMsgSDParamValue.1.2."exampleSDID@32473"."eventSource" = "Application" syslogMsgSDParamValue.1.3."exampleSDID@32473"."eventID" = "1011"
9. IANA Considerations
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The IANA has assigned value "192" under the 'mib-2' subtree and recorded the assignment in the SMI Numbers registry.
10. Security Considerations
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There are a number of management objects defined in this MIB module with a MAX-ACCESS clause of read-write and/or read-create. Such objects may be considered sensitive or vulnerable in some network environments. The support for SET operations in a non-secure environment without proper protection can have a negative effect on network operations. These are the tables and objects and their sensitivity/vulnerability:
- syslogMsgTableMaxSize: This object controls how many entries are kept in the syslogMsgTable. Unauthorized modifications may either cause increased memory consumption (by setting this object to a large value) or turn off the capability to retrieve notifications using GET class operations (by setting this object to zero). This might be used to hide traces of an attack.
- syslogMsgEnableNotifications: This object enables notifications. Unauthorized modifications to disable notification generation can be used to hide an attack by preventing management applications that use SNMP from receiving real-time notifications about events carried in SYSLOG messages. Unauthorized modifications to enable notification generation may be used as part of a denial-of-service attack against a network management system if, for example, the SYSLOG-to-SNMP translator accepts unauthorized SYSLOG messages.
Some of the readable objects in this MIB module (i.e., objects with a MAX-ACCESS other than not-accessible) may be considered sensitive or vulnerable in some network environments. It is thus important to control even GET and/or NOTIFY access to these objects and possibly to even encrypt the values of these objects when sending them over the network via SNMP. These are the tables and objects and their sensitivity/vulnerability:
o syslogMsgTableMaxSize, syslogMsgEnableNotifications: These objects provide information regarding whether SYSLOG messages are forwarded as SNMP notifications and how many messages will be maintained in the syslogMsgTable. This information might be exploited by an attacker in order to plan actions with the goal of hiding attack activities.- syslogMsgFacility, syslogMsgSeverity, syslogMsgVersion, syslogMsgTimeStamp, syslogMsgHostName, syslogMsgAppName, syslogMsgProcID, syslogMsgMsgID, syslogMsgSDParams, syslogMsgMsg, syslogMsgSDParamValue: These objects carry the content of SYSLOG messages and the SYSLOG-message-oriented security considerations of [RFC5424] apply. In particular, an attacker who gains access to SYSLOG messages via SNMP may use the knowledge gained from
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SYSLOG messages to compromise a machine or do other damage. It is therefore desirable to configure SNMP access control rules, enforcing a consistent security policy for SYSLOG messages.
SNMP versions prior to SNMPv3 did not include adequate security. Even if the network itself is secure (for example by using IPsec), even then, there is no control as to who on the secure network is allowed to access and GET/SET (read/change/create/delete) the objects in this MIB module.
It is RECOMMENDED that implementers consider the security features as provided by the SNMPv3 framework (see [RFC3410], section 8), including full support for the SNMPv3 cryptographic mechanisms (for authentication and privacy).
Further, deployment of SNMP versions prior to SNMPv3 is NOT RECOMMENDED. Instead, it is RECOMMENDED to deploy SNMPv3 and to enable cryptographic security. It is then a customer/operator responsibility to ensure that the SNMP entity giving access to an instance of this MIB module is properly configured to give access to the objects only to those principals (users) that have legitimate rights to indeed GET or SET (change/create/delete) them.
Using the security features of the SNMPv3 framework secures the transport of SYSLOG data via SNMP only. It is therefore RECOMMENDED that deployments use SYSLOG security mechanisms in order to prevent attackers from adding malicious SYSLOG data to the MIB tables.
11. Acknowledgments
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The editors wish to thank the following individuals for providing helpful comments on various versions of this document: Martin Bjorklund, Washam Fan, Rainer Gerhards, Wes Hardacker, David Harrington, Tom Petch, Juergen Quittek, Dan Romascanu, and Bert Wijnen.
12. References
12.1. Normative References
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[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2578] McCloghrie, K., Perkins, D., and J. Schoenwaelder, "Structure of Management Information Version 2 (SMIv2)", RFC 2578, STD 58, April 1999. [RFC2579] McCloghrie, K., Perkins, D., and J. Schoenwaelder, "Textual Conventions for SMIv2", RFC 2579, STD 58, April 1999. [RFC2580] McCloghrie, K., Perkins, D., and J. Schoenwaelder, "Conformance Statements for SMIv2", RFC 2580, STD 58, April 1999. [RFC3411] Harrington, D., Presuhn, R., and B. Wijnen, "An Architecture for Describing Simple Network Management Protocol (SNMP) Management Frameworks", STD 62, RFC 3411, December 2002. [RFC3412] Case, J., Harrington, D., Presuhn, R., and B. Wijnen, "Message Processing and Dispatching for the Simple Network Management Protocol (SNMP)", STD 62, RFC 3412, December 2002. [RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO 10646", STD 63, RFC 3629, November 2003. [RFC5424] Gerhards, R., "The Syslog Protocol", RFC 5424, March 2009. [RFC5427] Keeni, G., "Textual Conventions for Syslog Management", RFC 5427, March 2009. [RFC5675] Marinov, V. and J. Schoenwaelder, "Mapping Simple Network Management Protocol (SNMP) Notifications to SYSLOG Messages", RFC 5675, October 2009.
12.2. Informative References
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[RFC3014] Kavasseri, R., Ed., "Notification Log MIB", RFC 3014, November 2002. [RFC3410] Case, J., Mundy, R., Partain, D., and B. Stewart, "Introduction and Applicability Statements for Internet- Standard Management Framework", RFC 3410, December 2002.
Authors' Addresses
-
Juergen Schoenwaelder
Jacobs University Bremen
Campus Ring 1
28725 Bremen
GermanyEMail: j.schoenwaelder@jacobs-university.de
Alexander Clemm
Cisco Systems
170 West Tasman Drive
San Jose, CA 95134-1706
USAEMail:
alex@cisco.com
Anirban Karmakar
Cisco Systems India Pvt Ltd
SEZ Unit, Cessna Business Park,
Sarjapur Marathahalli ORR,
Bangalore, Karnataka 560103
IndiaEMail:
akarmaka@cisco.com