rfc2742.txt

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Network Working Group                                          L. Heintz
Request For Comments: 2742                                 Cisco Systems
Category: Standards Track                                       S. Gudur
                                                  Independent Consultant
                                                         M. Ellison, Ed.
                                       Ellison Software Consulting, Inc.
                                                            January 2000


       Definitions of Managed Objects for Extensible SNMP Agents


Status of this Memo

   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

   Copyright (C) The Internet Society (2000).  All Rights Reserved.

Abstract

   This memo defines a portion of the Management Information Base (MIB)
   for use with network management protocols in the Internet community.
   In particular, it describes objects managing SNMP agents that use the
   Agent Extensibility (AgentX) Protocol.

   This memo specifies a MIB module in a manner that is both compliant
   to the SMIv2, and semantically identical to the peer SMIv1
   definitions.

Table of Contents

   1. The SNMP Management Framework ...............................   2
   2. Introduction ................................................   3
   3. AgentX MIB Overview .........................................   3
   4. Managed Object Definitions for AgentX .......................   4
   5. Intellectual Property .......................................  15
   6. Acknowledgements ............................................  16
   7. Security Considerations .....................................  16
   8. References ..................................................  17
   9. Authors' and Editor's Addresses .............................  19
   10. Full Copyright Statement ...................................  20




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1.  The SNMP Management Framework

   The SNMP Management Framework presently consists of five major
   components:

   -  An overall architecture, described in RFC 2571 [1].

   -  Mechanisms for describing and naming objects and events for the
      purpose of management. The first version of this Structure of
      Management Information (SMI) is called SMIv1 and described in STD
      16, RFC 1155 [2], STD 16, RFC 1212 [3] and RFC 1215 [4]. The
      second version, called SMIv2, is described in STD 58, RFC 2578
      [5], STD 58, RFC 2579 [6] and STD 58, RFC 2580 [7].

   -  Message protocols for transferring management information. The
      first version of the SNMP message protocol is called SNMPv1 and
      described in STD 15, RFC 1157 [8]. A second version of the SNMP
      message protocol, which is not an Internet standards track
      protocol, is called SNMPv2c and described in RFC 1901 [9] and RFC
      1906 [10].  The third version of the message protocol is called
      SNMPv3 and described in RFC 1906 [10], RFC 2572 [11] and RFC 2574
      [12].

   -  Protocol operations for accessing management information. The
      first set of protocol operations and associated PDU formats is
      described in STD 15, RFC 1157 [8]. A second set of protocol
      operations and associated PDU formats is described in RFC 1905
      [13].

   -  A set of fundamental applications described in RFC 2573 [14] and
      the view-based access control mechanism described in RFC 2575
      [15].

   A more detailed introduction to the current SNMP Management Framework
   can be found in RFC 2570 [16].

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  Objects in the MIB are
   defined using the mechanisms defined in the SMI.

   This memo specifies a MIB module that is compliant to the SMIv2. A
   MIB conforming to the SMIv1 can be produced through the appropriate
   translations. The resulting translated MIB must be semantically
   equivalent, except where objects or events are omitted because no
   translation is possible (use of Counter64). Some machine readable
   information in SMIv2 will be converted into textual descriptions in





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   SMIv1 during the translation process. However, this loss of machine
   readable information is not considered to change the semantics of the
   MIB.

2.  Introduction

   The SNMP Agent Extensibility Protocol (AgentX) is a protocol used to
   distribute the implementation of an SNMP agent amongst a single
   "master agent" and multiple "subagents". See [17] for details about
   the AgentX protocol.

   The goals of the AgentX MIB are:

   -  List the set of subagent connections that currently have logical
      sessions open with the master agent.

   -  Identify each subagent connection transport address and type.

   -  Identify each subagent session vendor, AgentX protocol version,
      and other characteristics.

   -  Identify the set of MIB objects each session implements, the
      context in which the objects are registered, and the priority of
      the registration.

   -  Determine protocol operational parameters such as the timeout
      interval for responses from a session and the priority at which a
      session registers a particular MIB region.

   -  Allow (but do not require) managers to explicitly close subagent
      sessions with the master agent.

3.  AgentX MIB Overview

   This MIB is organized into four groups.  The agentxGeneral group
   provides information describing the master agent's AgentX support,
   including the protocol version supported.  The agentxConnection group
   provides information describing the current set of connections
   capable of carrying AgentX sessions.  The agentxSession group
   provides information describing the current set of AgentX sessions.
   The agentxRegistration group provides information describing the
   current set of registrations.

   Three tables form the heart of this mib.  These are the connection,
   session, and registration tables.






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   Entries in the registration table exist in a many-to-one relationship
   with entries in the session table.  This relationship is expressed
   through the two common indices, agentxSessionIndex and
   agentxConnIndex.  Entries in the registration table also exist in a
   many-to-one relationship with entries in the connection table.  This
   relationship is expressed through the common index, agentxConnIndex.

   Entries in the session table exist in a many-to-one relationship with
   entries in the connection table.  This relationship is expressed
   through the common index, agentxConnIndex.

4.  Managed Object Definitions for AgentX

AGENTX-MIB DEFINITIONS ::= BEGIN

IMPORTS
 MODULE-IDENTITY, OBJECT-TYPE, Unsigned32, mib-2
    FROM SNMPv2-SMI
 SnmpAdminString
    FROM SNMP-FRAMEWORK-MIB
 MODULE-COMPLIANCE, OBJECT-GROUP
    FROM SNMPv2-CONF
 TEXTUAL-CONVENTION, TimeStamp, TruthValue, TDomain
    FROM SNMPv2-TC;
agentxMIB MODULE-IDENTITY
 LAST-UPDATED "200001100000Z" -- Midnight 10 January 2000
 ORGANIZATION "AgentX Working Group"
 CONTACT-INFO "WG-email:   [e-mail]
               Subscribe:  [e-mail]
               WG-email Archive:  ftp://ftp.peer.com/pub/agentx/archives
               FTP repository:  ftp://ftp.peer.com/pub/agentx
               http://www.ietf.org/html.charters/agentx-charter.html

               Chair:      Bob Natale
                           ACE*COMM Corporation
               Email:      [e-mail]

               WG editor:  Mark Ellison
                           Ellison Software Consulting, Inc.
               Email:      [e-mail]

               Co-author:  Lauren Heintz
                           Cisco Systems,
               EMail:      [e-mail]

               Co-author:  Smitha Gudur
                           Independent Consultant
               Email:      [e-mail]



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              "
 DESCRIPTION    "This is the MIB module for the SNMP Agent Extensibility
     Protocol (AgentX).  This MIB module will be implemented by
     the master agent.
    "

  REVISION     "200001100000Z" -- Midnight 10 January 2000
 DESCRIPTION
    "Initial version published as RFC 2742."

  ::= { mib-2  74 }

 -- Textual Conventions

 AgentxTAddress ::= TEXTUAL-CONVENTION
   STATUS       current
   DESCRIPTION
     "Denotes a transport service address.  This is identical to
      the TAddress textual convention (SNMPv2-SMI) except that
      zero-length values are permitted.
     "
   SYNTAX       OCTET STRING (SIZE (0..255))

 -- Administrative assignments

 agentxObjects OBJECT IDENTIFIER      ::= { agentxMIB 1 }
 agentxGeneral OBJECT IDENTIFIER      ::= { agentxObjects 1 }
 agentxConnection OBJECT IDENTIFIER   ::= { agentxObjects 2 }
 agentxSession OBJECT IDENTIFIER      ::= { agentxObjects 3 }
 agentxRegistration OBJECT IDENTIFIER ::= { agentxObjects 4 }

 agentxDefaultTimeout OBJECT-TYPE
  SYNTAX      INTEGER (0..255)
  UNITS       "seconds"
  MAX-ACCESS  read-only
  STATUS      current
  DESCRIPTION
     "The default length of time, in seconds, that the master
      agent should allow to elapse after dispatching a message
      to a session before it regards the subagent as not
      responding.  This is a system-wide value that may
      override the timeout value associated with a particular
      session (agentxSessionTimeout) or a particular registered
      MIB region (agentxRegTimeout).  If the associated value of
      agentxSessionTimeout and agentxRegTimeout are zero, or
      impractical in accordance with implementation-specific
      procedure of the master agent, the value represented by
      this object will be the effective timeout value for the



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      master agent to await a response to a dispatch from a
      given subagent.
     "
  DEFVAL      { 5 }
  ::= { agentxGeneral 1 }

 agentxMasterAgentXVer OBJECT-TYPE
  SYNTAX      INTEGER (1..255)
  MAX-ACCESS  read-only
  STATUS      current
  DESCRIPTION
     "The AgentX protocol version supported by this master agent.
      The current protocol version is 1.  Note that the master agent
      must also allow interaction with earlier version subagents.
     "
  ::= { agentxGeneral 2 }

 --      The AgentX Subagent Connection Group

 agentxConnTableLastChange OBJECT-TYPE
  SYNTAX      TimeStamp
  MAX-ACCESS  read-only
  STATUS      current
  DESCRIPTION
     "The value of sysUpTime when the last row creation or deletion
      occurred in the agentxConnectionTable.
     "
  ::= { agentxConnection 1 }

 agentxConnectionTable OBJECT-TYPE
   SYNTAX      SEQUENCE OF AgentxConnectionEntry
   MAX-ACCESS  not-accessible
   STATUS      current
   DESCRIPTION
     "The agentxConnectionTable tracks all current AgentX transport
      connections.  There may be zero, one, or more AgentX sessions
      carried on a given AgentX connection.
     "
   ::= { agentxConnection 2 }

 agentxConnectionEntry OBJECT-TYPE
   SYNTAX      AgentxConnectionEntry
   MAX-ACCESS  not-accessible
   STATUS      current

   DESCRIPTION
     "An agentxConnectionEntry contains information describing a
      single AgentX transport connection.  A connection may be



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      used to support zero or more AgentX sessions.  An entry is
      created when a new transport connection is established,
      and is destroyed when the transport connection is terminated.
     "
   INDEX { agentxConnIndex }
   ::= { agentxConnectionTable 1 }

 AgentxConnectionEntry ::= SEQUENCE {
          agentxConnIndex            Unsigned32,
          agentxConnOpenTime         TimeStamp,
          agentxConnTransportDomain  TDomain,
          agentxConnTransportAddress AgentxTAddress }

 agentxConnIndex OBJECT-TYPE
   SYNTAX       Unsigned32 (1..4294967295)
   MAX-ACCESS   not-accessible
   STATUS       current
   DESCRIPTION
     "agentxConnIndex contains the value that uniquely identifies
      an open transport connection used by this master agent
      to provide AgentX service.  Values of this index should
      not be re-used.  The value assigned to a given transport
      connection is constant for the lifetime of that connection.
     "
   ::= { agentxConnectionEntry 1 }

 agentxConnOpenTime OBJECT-TYPE
   SYNTAX       TimeStamp
   MAX-ACCESS   read-only
   STATUS       current
   DESCRIPTION
     "The value of sysUpTime when this connection was established
      and, therefore, its value when this entry was added to the table.