rfc1565.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

Network Working Group                                 S. Kille, WG Chair
Request for Comments: 1565                              ISODE Consortium
Category: Standards Track                               N. Freed, Editor
                                                                Innosoft
                                                            January 1994


                    Network Services Monitoring MIB

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.

Table of Contents

   1. Introduction ................................................. 2
   2. The SNMPv2 Network Management Framework ...................... 2
   2.1 Object Definitions .......................................... 3
   3. Rationale for having a Network Services Monitoring MIB ....... 3
   3.1 General Relationship to Other MIBs .......................... 4
   3.2 Restriction of Scope ........................................ 4
   3.3 Relationship to Directory Services .......................... 4
   4. Application Objects .......................................... 5
   5. Definitions .................................................. 6
   6. Acknowledgements .............................................16
   7. References ...................................................16
   8. Security Considerations ......................................16
   9. Authors' Addresses ...........................................17



















Kille & Freed                                                   [Page 1]

RFC 1565            Network Services Monitoring MIB         January 1994


1.  Introduction

   There are a wide range of networked applications for which it is
   appropriate to provide SNMP Monitoring.  This includes both TCP/IP
   and OSI applications.  This document defines a MIB which contains the
   elements common to the monitoring of any network service application.
   This information includes a table of all monitorable network service
   applications, a count of the associations (connections) to each
   application, and basic information about the parameters and status of
   each application-related association.

   This MIB may be used on its own for any application, and for most
   simple applications this will suffice.  This MIB is also designed to
   serve as a building block which can be used in conjunction with
   application-specific monitoring and management.  Two examples of this
   are MIBs defining additional variables for monitoring a Message
   Transfer Agent (MTA) service or a Directory Service Agent (DSA)
   service. It is expected that further MIBs of this nature will be
   specified.

   This MIB does not attempt to provide facilities for management of the
   host or hosts the network service application runs on, nor does it
   provide facilities for monitoring applications that provide something
   other than a network service.  Host resource and general application
   monitoring is handled by the Host Resources MIB.

2.  The SNMPv2 Network Management Framework

   The SNMPv2 Network Management Framework consists of four major
   components.  They are:

      o  RFC 1442 [1] which defines the SMI, the mechanisms used for
         describing and naming objects for the purpose of management.

      o  STD 17, RFC 1213 [2] defines MIB-II, the core set of managed
         objects for the Internet suite of protocols.

      o  RFC 1445 [3] which defines the administrative and other
         architectural aspects of the framework.

      o  RFC 1448 [4] which defines the protocol used for network
         access to managed objects.

   The Framework permits new objects to be defined for the purpose of
   experimentation and evaluation.






Kille & Freed                                                   [Page 2]

RFC 1565            Network Services Monitoring MIB         January 1994


2.1  Object Definitions

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  Objects in the MIB are
   defined using the subset of Abstract Syntax Notation One (ASN.1)
   defined in the SMI.  In particular, each object type is named by an
   OBJECT IDENTIFIER, an administratively assigned name.  The object
   type together with an object instance serves to uniquely identify a
   specific instantiation of the object.  For human convenience, we
   often use a textual string, termed the descriptor, to refer to the
   object type.

3.  Rationale for having a Network Services Monitoring MIB

   Much effort has been expended in developing tools to manage lower
   layer network facilities.  However, relatively little work has been
   done on managing application layer entities.  It is neither efficient
   nor reasonable to manage all aspects of application layer entities
   using only lower layer information.  Moreover, the difficulty of
   managing application entities in this way increases dramatically as
   application entities become more complex.

   This leads to a substantial need to monitor applications which
   provide network services, particularly distributed components such as
   MTAs and DSAs, by monitoring specific aspects of the application
   itself.  Reasons to monitor such components include but are not
   limited to measuring load, detecting broken connectivity, isolating
   system failures, and locating congestion.

   In order to manage network service applications effectively two
   requirements must be met:

      (1)  It must be possible to monitor a large number of components
           (typical for a large organization).

      (2)  Application monitoring must be integrated into general
           network management.

   This specification defines simple read-only access; this is
   sufficient to determine up/down status and provide an indication of a
   broad class of operational problems.










Kille & Freed                                                   [Page 3]

RFC 1565            Network Services Monitoring MIB         January 1994


3.1  General Relationship to Other MIBs

   This MIB is intended to only provide facilities common to the
   monitoring of any network service application.  It does not provide
   all the facilities necessary to monitor any specific application.
   Each specific type of network service application is expected to have
   a MIB of its own that makes use of these common facilities.

3.2  Restriction of Scope

   The framework provided here is very minimal; there is a lot more that
   could be done. For example:

   (1)  General network service application configuration monitoring and
        control.

   (2)  Detailed examination and modification of individual entries in
        service-specific request queues.

   (3)  Probing to determine the status of a specific request (e.g. the
        location of a mail message with a specific message-id).

   (4)  Requesting that certain actions be performed (e.g. forcing an
        immediate connection and transfer of pending messages to some
        specific system).

   All these capabilities are both impressive and useful.  However,
   these capabilities would require provisions for strict security
   checking.  These capabilities would also mandate a much more complex
   design, with many characteristics likely to be fairly
   implementation-specific.  As a result such facilities are likely to
   be both contentious and difficult to implement.

   This document religiously keeps things simple and focuses on the
   basic monitoring aspect of managing applications providing network
   services.  The goal here is to provide a framework which is simple,
   useful, and widely implementable.

3.3  Relationship to Directory Services

   Use of and management of directory services already is tied up with
   network service application management.  There are clearly many
   things which could be dealt with by directory services and protocols.
   We take the line here that static configuration information is both
   provided by and dealt with by directory services and protocols.  The
   emphasis here is on transient application status.





Kille & Freed                                                   [Page 4]

RFC 1565            Network Services Monitoring MIB         January 1994


   By placing static information in the directory, the richness and
   linkage of the directory information framework does not need to be
   repeated in the MIB.  Static information is information which has a
   mean time to change of the order of days or longer.

   When information about network service applications is stored in the
   directory (regardless of whether or not the network service
   application makes direct use of the directory), it is recommended
   that a linkage be established, so that:

   (1)  The managed object contains its own directory name.  This allows
        all directory information to be obtained by reference.  This will
        let a SNMP monitor capable of performing directory queries
        present this information to the manager in an appropriate format.
        It is intended that this will be the normal case.

   (2)  The directory will reference the location of the SNMP agent, so
        that an SNMP capable directory query agent could probe dynamic
        characteristics of the object.

   (3)  This approach could be extended further, so that the SNMP
        attributes are modelled as directory attributes.  This would
        dramatically simplify the design of directory service agents that
        use SNMP to obtain the information they need.

4.  Application Objects

   This MIB defines a set of general purpose attributes which would be
   appropriate for a range of applications that provide network
   services.  Both OSI and non-OSI services can be accomodated.
   Additional tables defined in extensions to this MIB provide
   attributes specific to specific network services.

   A table is defined which will have one row for each network service
   application running on the system.  The only static information held
   on the application is its name.  All other static information should
   be obtained from various directory services.  The applDirectoryName
   is an external key, which allows an SNMP MIB entry to be cleanly
   related to the X.500 Directory.  In SNMP terms, the applications are
   grouped in a table called applTable, which is indexed by an integer
   key applIndex.

   The type of the application will be determined by one or both of:

   (1)  Additional MIB variables specific to the applications.

   (2)  An association to the application of a specific protocol.




Kille & Freed                                                   [Page 5]

RFC 1565            Network Services Monitoring MIB         January 1994


5.  Definitions

   APPLICATION-MIB DEFINITIONS ::= BEGIN

   IMPORTS
       OBJECT-TYPE, Counter32, Gauge32
         FROM SNMPv2-SMI
       mib-2
         FROM RFC1213-MIB
       DisplayString, TimeStamp
         FROM SNMPv2-TC;


   -- Textual conventions

   -- DistinguishedName [5] is used to refer to objects in the
   -- directory.

   DistinguishedName ::= TEXTUAL-CONVENTION
       STATUS current
       DESCRIPTION
           "A Distinguished Name represented in accordance with
            RFC1485."
       SYNTAX DisplayString

   application MODULE-IDENTITY
       LAST-UPDATED "9311280000Z"
       ORGANIZATION "IETF Mail and Directory Management Working Group"
       CONTACT-INFO
         "        Ned Freed

          Postal: Innosoft International, Inc.
                  250 West First Street, Suite 240
                  Claremont, CA  91711
                  US

             Tel: [phone]
             Fax: [phone]

          E-Mail: [e-mail]"
       DESCRIPTION
         "The MIB module describing network service applications"
       ::= { mib-2 27 }

   -- The basic applTable contains a list of the application
   -- entities.





Kille & Freed                                                   [Page 6]

RFC 1565            Network Services Monitoring MIB         January 1994


   applTable OBJECT-TYPE
       SYNTAX SEQUENCE OF ApplEntry
       MAX-ACCESS not-accessible
       STATUS current
       DESCRIPTION
           "The table holding objects which apply to all different
            kinds of applications providing network services."
       ::= {application 1}

   applEntry OBJECT-TYPE
       SYNTAX ApplEntry
       MAX-ACCESS not-accessible
       STATUS current
       DESCRIPTION
         "An entry associated with a network service application."
       INDEX {applIndex}
       ::= {applTable 1}

   ApplEntry ::= SEQUENCE {
       applIndex
           INTEGER,
       applName
           DisplayString,
       applDirectoryName
           DistinguishedName,
       applVersion
           DisplayString,
       applUptime
           TimeStamp,
       applOperStatus
           INTEGER,
       applLastChange
           TimeStamp,
       applInboundAssociations
           Gauge32,
       applOutboundAssociations
           Gauge32,
       applAccumulatedInboundAssociations
           Counter32,
       applAccumulatedOutboundAssociations
           Counter32,
       applLastInboundActivity
           TimeStamp,
       applLastOutboundActivity
           TimeStamp,
       applRejectedInboundAssociations
           Counter32,
       applFailedOutboundAssociations



Kille & Freed                                                   [Page 7]

RFC 1565            Network Services Monitoring MIB         January 1994


           Counter32
   }

   applIndex OBJECT-TYPE
       SYNTAX INTEGER (1..2147483647)
       MAX-ACCESS not-accessible
       STATUS current
       DESCRIPTION
         "An index to uniquely identify the network service
          application."
       ::= {applEntry 1}

   applName OBJECT-TYPE
       SYNTAX DisplayString
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
         "The name the network service application chooses to be
          known by."
       ::= {applEntry 2}

   applDirectoryName OBJECT-TYPE
       SYNTAX DistinguishedName
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
         "The Distinguished Name of the directory entry where
          static information about this application is stored.
          An empty string indicates that no information about
          the application is available in the directory."
       ::= {applEntry 3}

   applVersion OBJECT-TYPE
       SYNTAX DisplayString
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
         "The version of network service application software."
       ::= {applEntry 4}












Kille & Freed                                                   [Page 8]

RFC 1565            Network Services Monitoring MIB         January 1994


   applUptime OBJECT-TYPE
       SYNTAX TimeStamp
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
         "The value of sysUpTime at the time the network service
          application was last initialized.  If the application was
          last initialized prior to the last initialization of the
          network management subsystem, then this object contains
          a zero value."
       ::= {applEntry 5}

   applOperStatus OBJECT-TYPE
       SYNTAX INTEGER {
         up(1),
         down(2),
         halted(3),
         congested(4),
         restarting(5)
       }
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
         "Indicates the operational status of the network service