Network Working Group                                            D. Levi
Request for Comments: 2592                               Nortel Networks
Category: Standards Track                               J. Schoenwaelder
                                                        TU Braunschweig
                                                               May 1999


                Definitions of Managed Objects for the
                   Delegation of Management Scripts

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 (1999).  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 a set of managed objects that allow the
  delegation of management scripts to distributed managers.

Table of Contents

  1. Introduction .................................................   2
  2. The SNMP Management Framework ................................   2
  3. Overview .....................................................   3
  3.1 Terms ......................................................    4
  4. Requirements and Design Issues ..............................    5
  4.1 Script Languages ...........................................    5
  4.2 Script Transfer ............................................    6
  4.3 Script Execution ...........................................    7
  5. The Structure of the MIB .....................................   8
  5.1 The smLanguageGroup ........................................    9
  5.2 The smScriptGroup ..........................................    9
  5.3 The smCodeGroup ............................................   10
  5.4 The smLaunchGroup ..........................................   10
  5.5 The smRunGroup .............................................   11
  6 Definitions ..................................................   11
  7. Usage Examples ...............................................  41
  7.1 Pushing a script via SNMP ..................................   41



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  7.2 Pulling a script from a URL ................................   42
  7.3 Modifying an existing script ...............................   42
  7.4 Removing an existing script ................................   43
  7.5 Creating a launch button ...................................   43
  7.6 Launching a script .........................................   44
  7.7 Terminating a script .......................................   44
  7.8 Removing a launch button ...................................   45
  8. VACM Configuration Examples ..................................  45
  8.1 Sandbox for guests .........................................   45
  8.2 Sharing scripts ............................................   46
  8.3 Emergency scripts ..........................................   47
  9. IANA Considerations ..........................................  48
  10. Security Considerations .....................................  48
  11. Intellectual Property .......................................  49
  12.  Acknowledgments ............................................. 49
  13. References ..................................................  50
  14. Editors' Addresses ..........................................  52
  16. Full Copyright Statement ....................................  53

1.  Introduction

  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 a set of managed objects that allow the
  delegation of management scripts to distributed managers.

  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 RFC 2119 [21].

2.  The SNMP Management Framework

  The SNMP Management Framework presently consists of five major
  components:

     o   An overall architecture, described in RFC 2271 [1].

     o   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], RFC 2579 [6] and RFC 2580 [7].








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     o   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
         2272 [11] and RFC 2274 [12].

     o   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].

     o   A set of fundamental applications described in RFC 2273 [14]
         and the view-based access control mechanism described in RFC
         2275 [15].

  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.

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

3.  Overview

  The Script MIB module defined in this memo can be used to delegate
  management functions to distributed managers. Management functions
  are defined as management scripts written in a management scripting
  language. This MIB makes no assumptions about the language itself and
  even allows distribution of compiled native code, if an
  implementation is able to execute native code under the control of
  this MIB.

  The Script MIB defines a standard interface for the delegation of
  management functions based on the Internet management framework. In
  particular, it provides the following capabilities:

  1.   Capabilities to transfer management scripts to a distributed
       manager.



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  2.   Capabilities for initiating, suspending, resuming and
       terminating management scripts.

  3.   Capabilities to transfer arguments for management scripts.

  4.   Capabilities to monitor and control running management scripts.

  5.   Capabilities to transfer the results produced by running
       management scripts.

  This memo does not address any additional topics like the generation
  of notifications or how to address remote agents from a Script MIB
  implementation.

3.1.  Terms

  This section defines the terms used throughout this memo.

  o    A `distributed manager' is a processing entity which is capable
       of performing network management functions. For the scope of
       this memo, a distributed manager is assumed to implement the
       Script MIB.

  o    A `higher-level manager', or just `manager', is a processing
       entity or human who initiates and controls the operations
       performed by one or more distributed managers.

  o    A `management script' is a set of instructions written in an
       executable language which implements a management function.

  o    A `management scripting language' is a language used to write
       management scripts. Note, the term scripting language does not
       imply that the language must have the characteristics of
       scripting languages (e.g. string orientation, interpretation,
       weak typing). The MIB defined in this memo also allows to
       control management scripts written in arbitrary compiled system
       programming languages.

  o    A `distributed manager' can be decomposed into an `SNMP entity'
       which implements the Script MIB defined in this memo and the
       `runtime system' that executes scripts. The Script MIB sees the
       runtime system as the managed resource which is controlled by
       the MIB.

       The runtime system can act as an SNMP application, according to
       the SNMP architecture defined in RFC 2271 [1]. For example, a
       runtime system which sends SNMP requests to other SNMP entities
       will act as a command generator application. The SNMP



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       applications in the runtime system may use the same SNMP engine
       which also serves the command responder application used to
       implement the Script MIB, but they are not required to do so.

  o    A `launch button' is the conceptual button used to start the
       execution of a management script. It assignes control parameters
       to a management script. In particular, it defines the ownership
       of the scripts started from a launch button. The ownership can
       be used by the language runtime system to enforce security
       profiles on a running management script.

4.  Requirements and Design Issues

  This section discusses some general requirements that have influenced
  the design of the Script MIB.

  o    The Script MIB must not make any assumptions about specific
       languages or runtime systems.

  o    The Script MIB must provide mechanisms that help to avoid new
       management problems (e.g. script version problems).

  o    The Script MIB must provide SNMP interfaces to all functions
       required to delegate management scripts. However, other
       protocols might be used in addition if they provide a
       significant improvement in terms of convenience for
       implementation or performance.

  o    The Script MIB must be organized so that access can be
       controlled effectively by using view-based access control [15].

  The following sections discuss some design issues in more detail.

4.1.  Script Languages

  The Script MIB defined in this memo makes no assumption about the
  script language. This MIB can therefore be used in combination with
  different languages (such as Tcl or Java) and/or different versions
  of the same language. No assumptions are made about the format in
  which management scripts are transferred.

  The Script MIB provides access to information about the language
  versions supported by a Script MIB implementation so that a manager
  can learn about the capabilities provided by an implementation.
  Languages and language versions are identified as follows:






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  1.   The language is identified by an object identifier. Object
       identifier for well-known languages will be registered by the
       Internet Assigned Numbers Authority (IANA). Enterprise specific
       languages can also be registered in the enterprise specific OID
       subtree.

  2.   A particular version of a language is identified by a language
       version number. The combination of a language object identifier
       and a language version is in most cases sufficient to decide
       whether a script can be executed or not.

  3.   Different implementations of the same language version might
       have differences due to ambiguities in the language definition
       or additional language features provided by an implementor. An
       additional object identifier value is provided which identifies
       the organization which provides the implementation of a
       language. This might be used by scripts that require a
       particular implementation of a language.

  4.   Finally, there might be different versions of a language
       implementation. A version number for the language implementation
       is provided so that the manager can also distinguish between
       different implementations from the same organization of a
       particular language version.

  The version numbers can either be used by a manager to select the
  language version required to execute a particular script or to select
  a script that fits the language versions supported by a particular
  Script MIB implementation.

  An additional table lists language extensions that provide features
  not provided by the core language. Language extensions are usually
  required to turn a general purpose language into a management
  language. In many cases, language extensions will come in the form of
  libraries that provide capabilities like sending SNMP requests to
  remote SNMP agents or accessing the local MIB instrumentation. Every
  extension is associated with a language and carries its own version
  numbers.

4.2.  Script Transfer

  There are two different ways to transfer management scripts to a
  distributed manager. The first approach requires that the manager
  pushes the script to the distributed manager. This is therefore
  called the `push model'. The second approach is the `pull model'
  where the manager tells the distributed manager the location of the
  script and the distributed manager retrieves the script itself.




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  The MIB defined in this memo supports both models. The `push model'
  is realized by a table which allows a manager to write scripts by
  sending a sequence of SNMP set requests. The script can be split into
  several fragments in order to deal with SNMP message size
  limitations.

  The `pull model' is realized by the use of Uniform Resource Locators
  (URLs) [17] that point to the script source. The manager writes the
  URL which points to the script source to the distributed manager by
  sending an SNMP set request. The distributed manager is then
  responsible for retrieving the document using the protocol specified
  in the URL. This allows the use of protocols like FTP [18] or HTTP
  [19] to transfer large management scripts efficiently.

  The Script MIB also allows management scripts that are hard-wired
  into the Script MIB implementation. Built-in scripts can either be
  implemented in a language runtime system, or they can be built
  natively into the Script MIB implementation. The implementation of
  the `push model' or the `pull model' is not required.

  Scripts can be stored in non-volatile storage. This allows a
  distributed manager to restart scripts if it is restarted (off-line
  restart). A manager is not required to push scripts back into the
  distributed manager after a restart if the script is backed up in
  non-volatile storage.

  Every script is identified by an administratively assigned name. This
  name may be used to derive the name which is used to access the
  script in non-volatile storage. This mapping is implementation
  specific. However, the mapping must ensure that the Script MIB
  implementation can handle scripts with the same administrative name
  owned by different managers. One way to achieve this is to use the
  script owner in addition to the script name in order to derive the
  internal name used to refer to a particular script in non-volatile
  storage.

4.3.  Script Execution

  The Script MIB permits execution of several instances of the same or
  different management scripts. Script arguments are passed as OCTET
  STRING values. Scripts return a single result value which is also an
  OCTET STRING value. The semantic interpretation of result values is
  left to the invoking manager or other management scripts. A script
  invoker must understand the format and semantics of both the
  arguments and the results of the scripts that it invokes.






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  Scripts can also export complex results through a MIB interface. This
  allows a management application to access and use script results in
  the same manner as it processes any other MIB data. However, the
  Script MIB does not provide any special support for the
  implementation of MIBs through scripts.

  Runtime errors terminate active scripts. An exit code and a human
  readable error message is left in the MIB. A notification containing
  the exit code, the error message and a timestamp is generated when a
  script terminates with an error exit code.

  Script arguments and results do not have any size limitations other
  than the limits imposed by the SMI and the SNMP protocol. However,
  implementations of this MIB might have further restrictions. A script
  designer might therefore choose to return the results via other
  mechanisms if the script results can be very large. One possibility
  is to return a URL as a script result which points to the file
  containing the script output.

  Executing scripts have a status object attached which allows script
  execution to be suspended, resumed, or aborted.  The precise
  semantics of the suspend and resume operations are language and
  runtime system dependent. Some runtime systems may choose to not
  implement the suspend/resume operations.

  A history of finished scripts is kept in the MIB. A script invoker
  can collect results at a later point in time (offline operation).
  Control objects can be used to control how entries in the history are
  aged out if the table fills up.

5.  The Structure of the MIB

  This section presents the structure of the MIB. The objects are
  arranged into the following groups:

  o    language group (smLanguageGroup)

  o    script group (smScriptGroup)

  o    script code group (smCodeGroup)

  o    script launch group (smLaunchGroup)

  o    running script group (smRunGroup)







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5.1.  The smLanguageGroup

  The smLanguageGroup is used to provide information about the
  languages and the language extensions supported by a Script MIB
  implementation.  This group includes two tables.  The smLangTable
  lists all languages supported by a Script MIB implementation and the
  smExtsnTable lists the extensions that are available for a given
  language.

5.2.  The smScriptGroup

  The smScriptGroup consists of a single table, called the
  smScriptTable. The smScriptTable lists all scripts known to a Script
  MIB implementation. The smScriptTable contains objects that allow the
  following operations:

  o    download scripts from a URL (pull model)

  o    read scripts from local non-volatile storage

  o    store scripts in local non-volatile storage

  o    delete scripts from local non-volatile storage

  o    list permanent scripts (that can not be changed or removed)

  o    read and modify the script status (enabled, disabled, editing)

  A status object called smScriptOperStatus allows a manager to obtain
  the current status of a script. It is also used to provide an error
  indication if an attempt to invoke one of the operations listed above
  fails. The status change of a script can be requested by modifying
  the associated smScriptAdminStatus object.

  The source of a script is defined by the smScriptSource object. This
  object may contain a URL pointing to a remote location which provides
  access to the management script. The script source is read from the
  smCodeTable (described below) or from non-volatile storage if the
  smScriptSource object contains an empty URL. The smScriptStorageType
  object is used to distinguish between scripts read from non-volatile
  storage and scripts read from the smCodeTable.

  Scripts are automatically loaded once the smScriptAdminStatus object
  is set to `enabled'.  Loading a script includes retrieving the script
  (probably from a remote location), compiling the script for languages
  that require a compilation step, and making the code available to the
  runtime system.  The smScriptOperStatus object is used to indicate
  the status of the loading process. This object will start in the



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  state `retrieving', switch to the state `compiling' and finally reach
  the state `enabled'. Errors during the retrieval or compilation phase
  will result in an error state such as `compilationFailed'.

5.3.  The smCodeGroup

  The smCodeGroup consists of a single table, called the smCodeTable,
  which provides the ability to transfer and modify scripts via SNMP
  set requests.  In particular, the smCodeTable allows the following
  operations:

  o    download scripts via SNMP (push model)

  o    modify scripts via SNMP (editing)

  The smCodeTable lists the code of a script. A script can be
  fragmented over multiple rows of the smCodeTable in order to handle
  SNMP message size limitations. Modifications of the smCodeTable are
  only possible if the associated smScriptOperStatus object has the
  value `editing'.  The Script MIB implementation reloads the modified
  script code once the smScriptOperStatus changes to `enabled' again.

  The implementation of the smCodeGroup is optional.

5.4.  The smLaunchGroup

  The smLaunchGroup contains a single table, the smLaunchTable. An
  entry in the smLaunchTable represents a launch button which can be
  used to start a script. The smLaunchTable allows the following
  operations:

  o    associate a script with an owner used during script execution

  o    provide arguments and parameters for script invocation

  o    invoke scripts with a single set operation

  The smLaunchTable describes scripts and their parameters that are
  ready to be launched. An entry in the smLaunchTable attaches an
  argument to a script and control values which, for example, define
  the maximum number of times that a script invoked from a particular
  row in the smLaunchTable may be running concurrently.

  An entry in the smLaunchTable also defines the owner which will be
  used to associate permissions with the script execution.






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5.5.  The smRunGroup

  The smRunGroup contains a single table, called the smRunTable, which
  lists all scripts that are currently running or have terminated
  recently. The smRunTable contains objects that allow the following
  operations:

  o    retrieve status information from running scripts

  o    control running scripts (suspend, resume, abort)

  o    retrieve results from recently terminated scripts

  o    control the remaining maximum lifetime of a running script

  o    control how long script results are accessible

  Every row in the smRunTable contains the argument passed during
  script invocation, the result produced by the script and the script
  exit code.  The smRunTable also provides information about the
  current run state as well as start and end time-stamps. There are
  three writable objects in the smRunTable. The smRunLifeTime object
  defines the maximum time a running script may run before it is
  terminated by the Script MIB implementation. The smRunExpireTime
  object defines the time that a completed script can stay in the
  smRunTable before it is aged out. The smRunControl object allows
  running scripts to be suspended, resumed, or aborted.

6.  Definitions

  DISMAN-SCRIPT-MIB DEFINITIONS ::= BEGIN

  IMPORTS
      MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE,
      Integer32, Unsigned32, mib-2
          FROM SNMPv2-SMI

      RowStatus, TimeInterval, DateAndTime, StorageType, DisplayString
          FROM SNMPv2-TC

      MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
          FROM SNMPv2-CONF

      SnmpAdminString
          FROM SNMP-FRAMEWORK-MIB;

  scriptMIB MODULE-IDENTITY
      LAST-UPDATED "9902221800Z"



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      ORGANIZATION "IETF Distributed Management Working Group"
      CONTACT-INFO
          "David B. Levi
           Nortel Networks
           4401 Great America Parkway
           Santa Clara, CA 95052-8185
           U.S.A.
           Tel: +1 423 686 0432
           E-mail: [email protected]

           Juergen Schoenwaelder
           TU Braunschweig
           Bueltenweg 74/75
           38106 Braunschweig
           Germany
           Tel: +49 531 391-3283
           E-mail: [email protected]"
      DESCRIPTION
          "This MIB module defines a set of objects that allow to
           delegate management scripts to distributed managers."
      ::= { mib-2 64 }

  --
  -- The groups defined within this MIB module:
  --

  smObjects       OBJECT IDENTIFIER ::= { scriptMIB 1 }
  smNotifications OBJECT IDENTIFIER ::= { scriptMIB 2 }
  smConformance   OBJECT IDENTIFIER ::= { scriptMIB 3 }

  --
  -- Script language and language extensions.
  --
  -- This group defines tables which list the languages and the
  -- language extensions supported by a script MIB implementation.
  -- Languages are uniquely identified by object identifier values.
  --

  smLangTable OBJECT-TYPE
      SYNTAX      SEQUENCE OF SmLangEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "This table lists supported script languages."
      ::= { smObjects 1 }

  smLangEntry OBJECT-TYPE
      SYNTAX      SmLangEntry



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      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "An entry describing a particular language."
      INDEX { smLangIndex }
      ::= { smLangTable 1 }

  SmLangEntry ::= SEQUENCE {
      smLangIndex         Integer32,
      smLangLanguage      OBJECT IDENTIFIER,
      smLangVersion       SnmpAdminString,
      smLangVendor        OBJECT IDENTIFIER,
      smLangRevision      SnmpAdminString,
      smLangDescr         SnmpAdminString
  }

  smLangIndex OBJECT-TYPE
      SYNTAX      Integer32 (1..2147483647)
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "The locally arbitrary, but unique identifier associated
           with this language entry.

           The value is expected to remain constant at least from one
           re-initialization of the entity's network management system
           to the next re-initialization.

           Note, the data type and the range of this object must be
           consistent with the definition of smScriptLanguage."
      ::= { smLangEntry 1 }

  smLangLanguage OBJECT-TYPE
      SYNTAX      OBJECT IDENTIFIER
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "The globally unique identification of the language."
      ::= { smLangEntry 2 }

  smLangVersion OBJECT-TYPE
      SYNTAX      SnmpAdminString (SIZE (0..32))
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "The version number of the language. The zero-length string
           shall be used if the language does not have a version
           number.



Levi & Schoenwaelder        Standards Track                    [Page 13]

RFC 2592                       Script MIB                       May 1999


           It is suggested that the version number consist of one or
           more decimal numbers separated by dots, where the first
           number is called the major version number."
      ::= { smLangEntry 3 }

  smLangVendor OBJECT-TYPE
      SYNTAX      OBJECT IDENTIFIER
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "An object identifer which identifies the vendor who
           provides the implementation of the language. This object
           identifer SHALL point to the object identifier directly
           below the enterprise object identifier {1 3 6 1 4 1}
           allocated for the vendor. The value must be the object
           identifier {0 0} if the vendor is not known."
      ::= { smLangEntry 4 }

  smLangRevision OBJECT-TYPE
      SYNTAX      SnmpAdminString (SIZE (0..32))
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "The version number of the language implementation.
           The value of this object must be an empty string if
           version number of the implementation is unknown.

           It is suggested that the value consist of one or more
           decimal numbers separated by dots, where the first
           number is called the major version number."
      ::= { smLangEntry 5 }

  smLangDescr OBJECT-TYPE
      SYNTAX      SnmpAdminString
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "A textual description of the language."
      ::= { smLangEntry 6 }


  smExtsnTable OBJECT-TYPE
      SYNTAX      SEQUENCE OF SmExtsnEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "This table lists supported language extensions."
      ::= { smObjects 2 }



Levi & Schoenwaelder        Standards Track                    [Page 14]

RFC 2592                       Script MIB                       May 1999


  smExtsnEntry OBJECT-TYPE
      SYNTAX      SmExtsnEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "An entry describing a particular language extension."
      INDEX { smLangIndex, smExtsnIndex }
      ::= { smExtsnTable 1 }

  SmExtsnEntry ::= SEQUENCE {
      smExtsnIndex        Integer32,
      smExtsnExtension    OBJECT IDENTIFIER,
      smExtsnVersion      SnmpAdminString,
      smExtsnVendor       OBJECT IDENTIFIER,
      smExtsnRevision     SnmpAdminString,
      smExtsnDescr        SnmpAdminString
  }

  smExtsnIndex OBJECT-TYPE
      SYNTAX      Integer32 (1..2147483647)
      MAX-ACCESS  not-accessible
      STATUS      current

      DESCRIPTION
          "The locally arbitrary, but unique identifier associated
           with this language extension entry.

           The value is expected to remain constant at least from one
           re-initialization of the entity's network management system
           to the next re-initialization."
      ::= { smExtsnEntry 1}

  smExtsnExtension OBJECT-TYPE
      SYNTAX      OBJECT IDENTIFIER
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "The globally unique identification of the language
           extension."
      ::= { smExtsnEntry 2 }

  smExtsnVersion OBJECT-TYPE
      SYNTAX      SnmpAdminString (SIZE (0..32))
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "The version number of the language extension.




Levi & Schoenwaelder        Standards Track                    [Page 15]

RFC 2592                       Script MIB                       May 1999


           It is suggested that the version number consist of one or
           more decimal numbers separated by dots, where the first
           number is called the major version number."
      ::= { smExtsnEntry 3 }

  smExtsnVendor OBJECT-TYPE
      SYNTAX      OBJECT IDENTIFIER
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "An object identifer which identifies the vendor who
           provides the implementation of the extension. The
           object identifer value should point to the OID node
           directly below the enterprise OID {1 3 6 1 4 1}
           allocated for the vendor. The value must by the object
           identifier {0 0} if the vendor is not known."
      ::= { smExtsnEntry 4 }

  smExtsnRevision OBJECT-TYPE
      SYNTAX      SnmpAdminString (SIZE (0..32))
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "The version number of the extension implementation.
           The value of this object must be an empty string if
           version number of the implementation is unknown.

           It is suggested that the value consist of one or more
           decimal numbers separated by dots, where the first
           number is called the major version number."
      ::= { smExtsnEntry 5 }

  smExtsnDescr OBJECT-TYPE
      SYNTAX      SnmpAdminString
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "A textual description of the language extension."
      ::= { smExtsnEntry 6 }


  --
  -- Scripts known by the Script MIB implementation.
  --
  -- This group defines a table which lists all known scripts.
  -- Scripts can be added and removed through manipulation of the
  -- smScriptTable.
  --



Levi & Schoenwaelder        Standards Track                    [Page 16]

RFC 2592                       Script MIB                       May 1999


  smScriptObjects OBJECT IDENTIFIER ::= { smObjects 3 }

  smScriptTable OBJECT-TYPE
      SYNTAX      SEQUENCE OF SmScriptEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "This table lists and describes locally known scripts."
      ::= { smScriptObjects 1 }

  smScriptEntry OBJECT-TYPE
      SYNTAX      SmScriptEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "An entry describing a particular script. Every script that
           is stored in non-volatile memory is required to appear in
           this script table."
      INDEX { smScriptOwner, smScriptName }
      ::= { smScriptTable 1 }
  SmScriptEntry ::= SEQUENCE {
      smScriptOwner       SnmpAdminString,
      smScriptName        SnmpAdminString,
      smScriptDescr       SnmpAdminString,
      smScriptLanguage    Integer32,
      smScriptSource      DisplayString,
      smScriptAdminStatus INTEGER,
      smScriptOperStatus  INTEGER,
      smScriptStorageType StorageType,
      smScriptRowStatus   RowStatus
  }

  smScriptOwner OBJECT-TYPE
      SYNTAX      SnmpAdminString (SIZE (0..32))
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "The manager who owns this row in the smScriptTable."
      ::= { smScriptEntry 1 }

  smScriptName OBJECT-TYPE
      SYNTAX      SnmpAdminString
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "The locally-unique, administratively assigned name for this
           script. This object allows an smScriptOwner to have multiple
           entries in the smScriptTable.



Levi & Schoenwaelder        Standards Track                    [Page 17]

RFC 2592                       Script MIB                       May 1999


           This value of this object may be used to derive the name
           (e.g. a file name) which is used by the Script MIB
           implementation to access the script in non-volatile
           storage. The details of this mapping are implementation
           specific. However, the mapping needs to ensure that scripts
           created by different owners with the same script name do not
           map to the same name in non-volatile storage."
      ::= { smScriptEntry 2 }

  smScriptDescr OBJECT-TYPE
      SYNTAX      SnmpAdminString
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "A description of the purpose of the script."
      ::= { smScriptEntry 3 }

  smScriptLanguage OBJECT-TYPE
      SYNTAX      Integer32 (0..2147483647)
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "The value of this object type identifies an entry in the
           smLangTable which is used to execute this script.
           The special value 0 may be used by hard-wired scripts
           that can not be modified and that are executed by
           internal functions.

           Note, the data type and the range of this object must be
           consistent with the definition of smLangIndex."
      ::= { smScriptEntry 4 }

  smScriptSource OBJECT-TYPE
      SYNTAX      DisplayString
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "This object either contains a reference to the script
           source or an empty string. A reference must be given
           in the form of a Uniform Resource Locator (URL) as
           defined in RFC 2396. The allowed character sets and the
           encoding rules defined in RFC 2396 section 2 apply.

           When the smScriptAdminStatus object is set to `enabled',
           the Script MIB implementation will `pull' the script
           source from the URL contained in this object if the URL
           is not empty.




Levi & Schoenwaelder        Standards Track                    [Page 18]

RFC 2592                       Script MIB                       May 1999


           An empty URL indicates that the script source is loaded
           from local storage. The script is read from the smCodeTable
           if the value of smScriptStorageType is volatile. Otherwise,
           the script is read from non-volatile storage.

           Note: This document does not mandate implementation of any
           specific URL scheme. A attempt to load a script from a
           nonsupported URL scheme will cause the smScriptOperStatus
           to report an `unknownProtocol' error.

           Set requests to change this object are invalid if the
           value of smScriptOperStatus is `enabled', `editing',
           `retrieving' or `compiling' and will result in an
           inconsistentValue error."
      DEFVAL { ''H }
      ::= { smScriptEntry 5 }
  smScriptAdminStatus OBJECT-TYPE
      SYNTAX      INTEGER {
                      enabled(1),
                      disabled(2),
                      editing(3)
                  }
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "The value of this object indicates the desired status of
           the script. See the definition of smScriptOperStatus for
           a description of the values.

           When the smScriptAdminStatus object is set to `enabled' and
           the smScriptOperStatus is `disabled' or one of the error
           states, the Script MIB implementation will `pull' the script
           source from the URL contained in the smScriptSource object
           if the URL is not empty."
      DEFVAL { disabled }
      ::= { smScriptEntry 6 }

  smScriptOperStatus OBJECT-TYPE
      SYNTAX      INTEGER {
                      enabled(1),
                      disabled(2),
                      editing(3),
                      retrieving(4),
                      compiling(5),
                      noSuchScript(6),
                      accessDenied(7),
                      wrongLanguage(8),
                      wrongVersion(9),



Levi & Schoenwaelder        Standards Track                    [Page 19]

RFC 2592                       Script MIB                       May 1999


                      compilationFailed(10),
                      noResourcesLeft(11),
                      unknownProtocol(12),
                      protocolFailure(13),
                      genericError(14)
                  }
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "The actual status of the script in the runtime system. The
           value of this object is only meaningful when the value of the
           smScriptRowStatus object is `active'.

           The smScriptOperStatus object may have the following values:
           - `enabled' indicates that the script is available and can
              be started by a launch table entry.

           - `disabled' indicates that the script can not be used.

           - `editing' indicates that the script can be modified in the
             smCodeTable.

           - `retrieving' indicates that the script is currently being
             loaded from non-volatile storage or a remote system.

           - `compiling' indicates that the script is currently being
             compiled by the runtime system.

           - `noSuchScript' indicates that the script does not exist
             at the smScriptSource.

           - `accessDenied' indicates that the script can not be loaded
             from the smScriptSource due to a lack of permissions.

           - `wrongLanguage' indicates that the script can not be loaded
             from the smScriptSource because of a language mismatch.

           - `wrongVersion' indicates that the script can not be loaded
             from the smScriptSource because of a language version
             mismatch.

           - `compilationFailed' indicates that the compilation failed.

           - `noResourcesLeft' indicates that the runtime system does
             not have enough resources to load the script.

           - `unknownProtocol' indicates that the script could not be
             loaded from the smScriptSource because the requested



Levi & Schoenwaelder        Standards Track                    [Page 20]

RFC 2592                       Script MIB                       May 1999


             protocol is not supported.

           - `protocolFailure' indicates that the script could not be
             loaded from the smScriptSource because of a protocol
             failure.

           - `genericError' indicates that the script could not be
             loaded due to an error condition not listed above.

           The `retrieving' and `compiling' states are transient states
           which will either lead to one of the error states or the
           `enabled' state. The `disabled' and `editing' states are
           administrative states which are only reached by explicit
           management operations.

           All launch table entries that refer to this script table
           entry shall have an smLaunchOperStatus value of `disabled'
           when the value of this object is not `enabled'."
      DEFVAL { disabled }
      ::= { smScriptEntry 7 }

  smScriptStorageType OBJECT-TYPE
      SYNTAX      StorageType
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "This object defines whether this row and the script
           controlled by this row are kept in volatile storage and
           lost upon reboot or if this row is backed up by
           non-volatile or permanent storage.

           The script controlled by this row is written into local
           non-volatile storage if the following condition becomes
           true:

           (a) the URL contained in the smScriptSource object is empty
               and
           (b) the smScriptStorageType is `nonVolatile'
               and
           (c) the smScriptOperStatus is `enabled'

           Setting this object to `volatile' removes a script from
           non-volatile storage if the script controlled by this row
           has been in non-volatile storage before. Attempts to set
           this object to permanent will always fail with an
           inconsistentValue error.

           The value of smScriptStorageType is only meaningful if the



Levi & Schoenwaelder        Standards Track                    [Page 21]

RFC 2592                       Script MIB                       May 1999


           value of the corresponding RowStatus object is `active'.

           If smScriptStorageType has the value permanent(4), then all
           objects whose MAX-ACCESS value is read-create must be
           writable, with the exception of the smScriptStorageType and
           smScriptRowStatus objects, which shall be read-only."
      DEFVAL { volatile }
      ::= { smScriptEntry 8 }

  smScriptRowStatus OBJECT-TYPE
      SYNTAX      RowStatus
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "A control that allows entries to be added and removed from
           this table.

           Changing the smScriptRowStatus from `active' to `notInService'
           will remove the associated script from the runtime system.
           The value of smScriptOperStatus will be reset to `disabled'.

           Deleting conceptual rows from this table includes the
           deletion of all resources associated with this row. This
           implies that a script stored in non-volatile storage is
           removed from non-volatile storage.

           An entry may not exist in the `active' state unless all
           required objects in the entry have appropriate values. Rows
           that are not complete or not in service are not known by the
           script runtime system.

           Attempts to `destroy' a row or to set a row `notInService'
           while the script is executing will result in an
           inconsistentValue error.

           Attempts to `destroy' a row or to set a row `notInService'
           where the value of the smScriptStorageType object is
           `permanent' or `readOnly' will result in an
           inconsistentValue error."
      ::= { smScriptEntry 9 }


  --
  -- Access to script code via SNMP
  --
  -- The smCodeTable allows script code to be read and modified
  -- via SNMP.
  --



Levi & Schoenwaelder        Standards Track                    [Page 22]

RFC 2592                       Script MIB                       May 1999


  smCodeTable OBJECT-TYPE
      SYNTAX      SEQUENCE OF SmCodeEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "This table contains the script code for scripts that are
           written via SNMP write operations."
      ::= { smScriptObjects 2 }

  smCodeEntry OBJECT-TYPE
      SYNTAX      SmCodeEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "An entry describing a particular fragment of a script."
      INDEX { smScriptOwner, smScriptName, smCodeIndex }
      ::= { smCodeTable 1 }

  SmCodeEntry ::= SEQUENCE {
      smCodeIndex         Unsigned32,
      smCodeText          OCTET STRING,
      smCodeRowStatus     RowStatus
  }

  smCodeIndex OBJECT-TYPE
      SYNTAX      Unsigned32 (1..4294967295)
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "The index value identifying this code fragment."
      ::= { smCodeEntry 1 }

  smCodeText OBJECT-TYPE
      SYNTAX      OCTET STRING (SIZE (1..1024))
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "The code that makes up a fragment of a script. The format
           of this code fragment depends on the script language which
           is identified by the associated smScriptLanguage object."
      ::= { smCodeEntry 2 }

  smCodeRowStatus OBJECT-TYPE
      SYNTAX      RowStatus
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "A control that allows entries to be added and removed from



Levi & Schoenwaelder        Standards Track                    [Page 23]

RFC 2592                       Script MIB                       May 1999


           this table."
      ::= { smCodeEntry 3 }

  --
  -- Script execution.
  --
  -- This group defines tables which allow script execution to be
  -- initiated, suspended, resumed, and terminated.  It also provides
  -- a mechanism for keeping a history of recent script executions
  -- and their results.
  --

  smRunObjects OBJECT IDENTIFIER ::= { smObjects 4 }

  smLaunchTable OBJECT-TYPE
      SYNTAX      SEQUENCE OF SmLaunchEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "This table lists and describes scripts that are ready
           to be executed together with their parameters."
      ::= { smRunObjects 1 }

  smLaunchEntry OBJECT-TYPE
      SYNTAX      SmLaunchEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "An entry describing a particular executable script."
      INDEX { smLaunchOwner, smLaunchName }
      ::= { smLaunchTable 1 }

  SmLaunchEntry ::= SEQUENCE {
      smLaunchOwner               SnmpAdminString,
      smLaunchName                SnmpAdminString,
      smLaunchScriptOwner         SnmpAdminString,
      smLaunchScriptName          SnmpAdminString,
      smLaunchArgument            OCTET STRING,
      smLaunchMaxRunning          Unsigned32,
      smLaunchMaxCompleted        Unsigned32,
      smLaunchLifeTime            TimeInterval,
      smLaunchExpireTime          TimeInterval,
      smLaunchStart               Integer32,
      smLaunchControl             INTEGER,
      smLaunchAdminStatus         INTEGER,
      smLaunchOperStatus          INTEGER,
      smLaunchRunIndexNext        Integer32,
      smLaunchStorageType         StorageType,



Levi & Schoenwaelder        Standards Track                    [Page 24]

RFC 2592                       Script MIB                       May 1999


      smLaunchRowStatus           RowStatus
  }

  smLaunchOwner OBJECT-TYPE
      SYNTAX      SnmpAdminString (SIZE (0..32))
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION

          "The manager who owns this row in the smLaunchTable. Every
           instance of a running script started from a particular entry
           in the smLaunchTable (i.e. entries in the smRunTable) will be
           owned by the same smLaunchOwner used to index the entry in
           the smLaunchTable. This owner is not necessarily the same as
           the owner of the script itself (smLaunchScriptOwner)."
      ::= { smLaunchEntry 1 }

  smLaunchName OBJECT-TYPE
      SYNTAX      SnmpAdminString (SIZE (1..32))
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "The locally-unique, administratively assigned name for this
           launch table entry. This object allows an smLaunchOwner to
           have multiple entries in the smLaunchTable. The smLaunchName
           is an arbitrary name that must be different from any other
           smLaunchTable entries with the same smLaunchOwner but can be
           the same as other entries in the smLaunchTable with different
           smLaunchOwner values. Note that the value of smLaunchName
           is not related in any way to the name of the script being
           launched."
      ::= { smLaunchEntry 2 }

  smLaunchScriptOwner OBJECT-TYPE
      SYNTAX      SnmpAdminString (SIZE (0..32))
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "The value of this object in combination with the value of
           smLaunchScriptName identifies the script that can be
           launched from this smLaunchTable entry. Attempts to write
           this object will fail with an inconsistentValue error if
           the value of smLaunchOperStatus is `enabled'."
      ::= { smLaunchEntry 3 }

  smLaunchScriptName OBJECT-TYPE
      SYNTAX      SnmpAdminString (SIZE (0..32))
      MAX-ACCESS  read-create



Levi & Schoenwaelder        Standards Track                    [Page 25]

RFC 2592                       Script MIB                       May 1999


      STATUS      current
      DESCRIPTION
          "The value of this object in combination with the value of
           the smLaunchScriptOwner identifies the script that can be
           launched from this smLaunchTable entry. Attempts to write
           this objects will fail with an inconsistentValue error if
           the value of smLaunchOperStatus is `enabled'."
      ::= { smLaunchEntry 4 }

  smLaunchArgument OBJECT-TYPE
      SYNTAX      OCTET STRING
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "The argument supplied to the script. When a script is
           invoked, the value of this object is used to initialize
           the smRunArgument object."
      DEFVAL { ''H }
      ::= { smLaunchEntry 5 }

  smLaunchMaxRunning OBJECT-TYPE
      SYNTAX      Unsigned32 (1..4294967295)
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "The maximum number of concurrently running scripts that may
           be invoked from this entry in the smLaunchTable. Lowering the
           current value of this object does not affect any scripts that
           are already executing."
      DEFVAL { 1 }
      ::= { smLaunchEntry 6 }

  smLaunchMaxCompleted OBJECT-TYPE
      SYNTAX      Unsigned32 (1..4294967295)
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "The maximum number of finished scripts invoked from this
           entry in the smLaunchTable allowed to be retained in the
           smRunTable. Whenever the value of this object is changed
           and whenever a script terminates, entries in the smRunTable
           are deleted if necessary until the number of completed
           scripts is smaller than the value of this object. Scripts
           whose smRunEndTime value indicates the oldest completion
           time are deleted first."
      DEFVAL { 1 }
      ::= { smLaunchEntry 7 }




Levi & Schoenwaelder        Standards Track                    [Page 26]

RFC 2592                       Script MIB                       May 1999


  smLaunchLifeTime OBJECT-TYPE
      SYNTAX      TimeInterval
      UNITS       "centi-seconds"
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "The default maximum amount of time a script launched
           from this entry may run. The value of this object is used
           to initialize the smRunLifeTime object when a script is
           launched. Changing the value of an smLaunchLifeTime
           instance does not affect scripts previously launched from
           this entry."
      DEFVAL { 360000 }
      ::= { smLaunchEntry 8 }

  smLaunchExpireTime OBJECT-TYPE
      SYNTAX      TimeInterval
      UNITS       "centi-seconds"
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "The default maximum amount of time information about a
           script launched from this entry is kept in the smRunTable
           after the script has completed execution.  The value of
           this object is used to initialize the smRunExpireTime
           object when a script is launched. Changing the value of an
           smLaunchExpireTime instance does not affect scripts
           previously launched from this entry."
      DEFVAL { 360000 }
      ::= { smLaunchEntry 9 }

  smLaunchStart OBJECT-TYPE
      SYNTAX      Integer32 (0..2147483647)
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "This object is used to start the execution of scripts.
           When retrieved, the value will be the value of smRunIndex
           for the last script that started execution by manipulating
           this object. The value will be zero if no script started
           execution yet.

           A script is started by setting this object to an unused
           smRunIndex value. A new row in the smRunTable will be
           created which is indexed by the value supplied by the
           set-request in addition to the value of smLaunchOwner and
           smLaunchName. An unused value can be obtained by reading
           the smLaunchRunIndexNext object.



Levi & Schoenwaelder        Standards Track                    [Page 27]

RFC 2592                       Script MIB                       May 1999


           Setting this object to the special value 0 will start
           the script with a self-generated smRunIndex value. The
           consequence is that the script invoker has no reliable
           way to determine the smRunIndex value for this script
           invocation and that the invoker has therefore no way
           to obtain the results from this script invocation. The
           special value 0 is however useful for scheduled script
           invocations.

           If this object is set, the following checks must be
           performed:

           1) The value of the smLaunchOperStatus object in this
              entry of the smLaunchTable must be `enabled'.
           2) The values of smLaunchScriptOwner and
              smLaunchScriptName of this row must identify an
              existing entry in the smScriptTable.
           3) The value of smScriptOperStatus of this entry must
              be `enabled'.
           4) The principal performing the set operation must have
              read access to the script. This must be checked by
              calling the isAccessAllowed abstract service interface
              defined in RFC 2271 on the row in the smScriptTable
              identified by smLaunchScriptOwner and smLaunchScriptName.
              The isAccessAllowed abstract service interface must be
              called on all columnar objects in the smScriptTable with
              a MAX-ACCESS value different than `not-accessible'. The
              test fails as soon as a call indicates that access is
              not allowed.
           5) If the value provided by the set operation is not 0,
              a check must be made that the value is currently not
              in use. Otherwise, if the value provided by the set
              operation is 0, a suitable unused value must be
              generated.
           6) The number of currently executing scripts invoked
              from this smLaunchTable entry must be less than
              smLaunchMaxRunning.

           Attempts to start a script will fail with an
           inconsistentValue error if one of the checks described
           above fails.

           Otherwise, if all checks have been passed, a new entry
           in the smRunTable will be created indexed by smLaunchOwner,
           smLaunchName and the new value for smRunIndex. The value
           of smLaunchArgument will be copied into smRunArgument,
           the value of smLaunchLifeTime will be copied to
           smRunLifeTime, and the value of smLaunchExpireTime



Levi & Schoenwaelder        Standards Track                    [Page 28]

RFC 2592                       Script MIB                       May 1999


           will be copied to smRunExpireTime.

           The smRunStartTime will be set to the current time and
           the smRunState will be set to `initializing' before the
           script execution is initiated in the appropriate runtime
           system.

           Note, the data type and the range of this object must
           be consistent with the smRunIndex object. Since this
           object might be written from the scheduling MIB, the
           data type Integer32 rather than Unsigned32 is used."
      DEFVAL { 0 }
      ::= { smLaunchEntry 10 }

  smLaunchControl OBJECT-TYPE
      SYNTAX      INTEGER {
                      abort(1),
                      suspend(2),
                      resume(3),
                      nop(4)
                  }
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "This object is used to request a state change for all
           running scripts in the smRunTable that were started from
           this row in the smLaunchTable.

           Setting this object to abort(1), suspend(2) or resume(3)
           will set the smRunControl object of all applicable rows
           in the smRunTable to abort(1), suspend(2) or resume(3)
           respectively. The phrase `applicable rows' means the set of
           rows which were created from this entry in the smLaunchTable
           and whose value of smRunState allows the corresponding
           state change as described in the definition of the
           smRunControl object. Setting this object to nop(4) has no
           effect."
      DEFVAL { nop }
      ::= { smLaunchEntry 11 }

  smLaunchAdminStatus OBJECT-TYPE
      SYNTAX      INTEGER {
                      enabled(1),
                      disabled(2)
                  }
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION



Levi & Schoenwaelder        Standards Track                    [Page 29]

RFC 2592                       Script MIB                       May 1999


          "The value of this object indicates the desired status of
           this launch table entry."
      DEFVAL { disabled }
      ::= { smLaunchEntry 12 }

  smLaunchOperStatus OBJECT-TYPE
      SYNTAX      INTEGER {
                      enabled(1),
                      disabled(2)
                  }
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "The value of this object indicates the actual status of
           this launch table entry. An `enabled' launch table
           entry can be used to start scripts while a `disabled'
           launch table entry will refuse any attempts to start
           scripts. The value `enabled' requires that the
           smLaunchRowStatus object is active. The value
           `disabled' requires that there are no entries in the
           smRunTable associated with this smLaunchTable entry."
      DEFVAL { disabled }
      ::= { smLaunchEntry 13 }

  smLaunchRunIndexNext OBJECT-TYPE
      SYNTAX      Integer32 (1..2147483647)
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "This variable is used for creating rows in the smRunTable.
           The value of this variable is a currently unused value
           for smRunIndex, which can be written into the smLaunchStart
           object associated with this row to launch a script.

           The value returned when reading this variable must be unique
           for the smLaunchOwner and smLauchName associated with this
           row. Subsequent attempts to read this variable must return
           different values.

           This variable will return the special value 0 if no new rows
           can be created.

           Note, the data type and the range of this object must be
           consistent with the definition of smRunIndex."
      ::= { smLaunchEntry 14 }

  smLaunchStorageType OBJECT-TYPE
      SYNTAX      StorageType



Levi & Schoenwaelder        Standards Track                    [Page 30]

RFC 2592                       Script MIB                       May 1999


      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "This object defines if this row is kept in volatile storage
           and lost upon reboot or if this row is backed up by stable
           storage.

           The value of smLaunchStorageType is only meaningful if the
           value of the corresponding RowStatus object is active.

           If smLaunchStorageType has the value permanent(4), then all
           objects whose MAX-ACCESS value is read-create must be
           writable, with the exception of the smLaunchStorageType and
           smLaunchRowStatus objects, which shall be read-only."
      DEFVAL { volatile }
      ::= { smLaunchEntry 15 }

  smLaunchRowStatus OBJECT-TYPE
      SYNTAX      RowStatus
      MAX-ACCESS  read-create
      STATUS      current
      DESCRIPTION
          "A control that allows entries to be added and removed from
           this table.

           Attempts to `destroy' a row or to set a row `notInService'
           while scripts started from this launch table entry are
           running will result in an inconsistentValue error.

           Attempts to `destroy' a row or to set a row `notInService'
           where the value of the smLaunchStorageType object is
           `permanent' or `readOnly' will result in an
           inconsistentValue error."
      ::= { smLaunchEntry 16 }


  smRunTable OBJECT-TYPE
      SYNTAX      SEQUENCE OF SmRunEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "This table lists and describes scripts that are currently
           running or have been running in the past."
      ::= { smRunObjects 2 }

  smRunEntry OBJECT-TYPE
      SYNTAX      SmRunEntry
      MAX-ACCESS  not-accessible



Levi & Schoenwaelder        Standards Track                    [Page 31]

RFC 2592                       Script MIB                       May 1999


      STATUS      current
      DESCRIPTION
          "An entry describing a particular running or finished
           script."
      INDEX { smLaunchOwner, smLaunchName, smRunIndex }
      ::= { smRunTable 1 }

  SmRunEntry ::= SEQUENCE {
      smRunIndex          Integer32,
      smRunArgument       OCTET STRING,
      smRunStartTime      DateAndTime,
      smRunEndTime        DateAndTime,
      smRunLifeTime       TimeInterval,
      smRunExpireTime     TimeInterval,
      smRunExitCode       INTEGER,
      smRunResult         OCTET STRING,
      smRunControl        INTEGER,
      smRunState          INTEGER,
      smRunError          SnmpAdminString
  }

  smRunIndex OBJECT-TYPE
      SYNTAX      Integer32 (1..2147483647)
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "The locally arbitrary, but unique identifier associated
           with this running or finished script. This value must be
           unique for all rows in the smRunTable with the same
           smLaunchOwner and smLaunchName.

           Note, the data type and the range of this object must be
           consistent with the definition of smLaunchRunIndexNext
           and smLaunchStart."
      ::= { smRunEntry 1 }

  smRunArgument OBJECT-TYPE
      SYNTAX      OCTET STRING
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "The argument supplied to the script when it started."
      DEFVAL { ''H }
      ::= { smRunEntry 2 }

  smRunStartTime OBJECT-TYPE
      SYNTAX      DateAndTime
      MAX-ACCESS  read-only



Levi & Schoenwaelder        Standards Track                    [Page 32]

RFC 2592                       Script MIB                       May 1999


      STATUS      current
      DESCRIPTION
          "The date and time when the execution started. The value
           '0000000000000000'H is returned if the script has not
           started yet."
      DEFVAL { '0000000000000000'H }
      ::= { smRunEntry 3 }

  smRunEndTime OBJECT-TYPE
      SYNTAX      DateAndTime
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "The date and time when the execution terminated. The value
           '0000000000000000'H is returned if the script has not
           terminated yet."
      DEFVAL { '0000000000000000'H }
      ::= { smRunEntry 4 }

  smRunLifeTime OBJECT-TYPE
      SYNTAX      TimeInterval
      UNITS       "centi-seconds"
      MAX-ACCESS  read-write
      STATUS      current
      DESCRIPTION
          "This object specifies how long the script can execute.
           This object returns the remaining time that the script
           may run. The object is initialized with the value of the
           associated smLaunchLifeTime object and ticks backwards.
           The script is aborted immediately when the value reaches 0.

           The value of this object may be set in order to increase or
           reduce the remaining time that the script may run. Setting
           this value to 0 will abort script execution immediately,
           and, if the value of smRunExpireTime is also 0, will remove
           this entry from the smRunTable once it has terminated.

           The value of smRunLifeTime reflects the real-time execution
           time as seen by the outside world. The value of this object
           will always be 0 for a script that finished execution, that
           is smRunState has the value `terminated'.

           The value of smRunLifeTime does not change while a script
           is suspended, that is smRunState has the value `suspended'.
           Note, this does not affect set operations. It is legal to
           modify smRunLifeTime via set operations while a script is
           suspended."
      ::= { smRunEntry 5 }



Levi & Schoenwaelder        Standards Track                    [Page 33]

RFC 2592                       Script MIB                       May 1999


  smRunExpireTime OBJECT-TYPE
      SYNTAX      TimeInterval
      UNITS       "centi-seconds"
      MAX-ACCESS  read-write
      STATUS      current
      DESCRIPTION
          "This value specifies how long this row can exist in the
           smRunTable after the script has terminated.  This object
           returns the remaining time that the row may exist before it
           is aged out. The object is initialized with the value of the
           associated smLaunchExpireTime object and ticks backwards. The
           entry in the smRunTable is destroyed when the value reaches 0
           and the smRunState has the value `terminated'.

           The value of this object may be set in order to increase or
           reduce the remaining time that the row may exist.  Setting
           the value to 0 will destroy this entry as soon as the
           smRunState has the value `terminated'."
      ::= { smRunEntry 6 }

  smRunExitCode OBJECT-TYPE
      SYNTAX      INTEGER {
                      noError(1),
                      halted(2),
                      lifeTimeExceeded(3),
                      noResourcesLeft(4),
                      languageError(5),
                      runtimeError(6),
                      invalidArgument(7),
                      securityViolation(8),
                      genericError(9)
                  }
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "The value of this object indicates the reason why a
           script finished execution. The smRunExitCode code may have
           one of the following values:

           - `noError', which indicates that the script completed
              successfully without errors;

           - `halted', which indicates that the script was halted
              by a request from an authorized manager;

           - `lifeTimeExceeded', which indicates that the script
              exited because a time limit was exceeded;




Levi & Schoenwaelder        Standards Track                    [Page 34]

RFC 2592                       Script MIB                       May 1999


           - `noResourcesLeft', which indicates that the script
              exited because it ran out of resources (e.g. memory);

           - `languageError', which indicates that the script exited
              because of a language error (e.g. a syntax error in an
              interpreted language);

           - `runtimeError', which indicates that the script exited
              due to a runtime error (e.g. a division by zero);

           - `invalidArgument', which indicates that the script could
              not be run because of invalid script arguments;

           - `securityViolation', which indicates that the script
              exited due to a security violation;

           - `genericError', which indicates that the script exited
              for an unspecified reason.

           If the script has not yet begun running, or is currently
           running, the value will be `noError'."
      DEFVAL { noError }
      ::= { smRunEntry 7 }

  smRunResult OBJECT-TYPE
      SYNTAX      OCTET STRING
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "The result value produced by the running script. Note that
           the result may change while the script is executing."
      DEFVAL { ''H }
      ::= { smRunEntry 8 }

  smRunControl OBJECT-TYPE
      SYNTAX      INTEGER {
                      abort(1),
                      suspend(2),
                      resume(3),
                      nop(4)
                  }
      MAX-ACCESS  read-write
      STATUS      current
      DESCRIPTION
          "The value of this object indicates the desired status of the
           script execution defined by this row.

           Setting this object to `abort' will abort execution if the



Levi & Schoenwaelder        Standards Track                    [Page 35]

RFC 2592                       Script MIB                       May 1999


           value of smRunState is `initializing', `executing',
           `suspending', `suspended' or `resuming'. Setting this object
           to `abort' when the value of smRunState is `aborting' or
           `terminated' will result in an inconsistentValue error.

           Setting this object to `suspend' will suspend execution
           if the value of smRunState is `executing'. Setting this
           object to `suspend' will cause an inconsistentValue error
           if the value of smRunState is not `executing'.

           Setting this object to `resume' will resume execution
           if the value of smRunState is `suspending' or
           `suspended'. Setting this object to `resume' will cause an
           inconsistentValue error if the value of smRunState is
           not `suspending' or `suspended'.

           Setting this object to nop(4) has no effect."
      DEFVAL { nop }
      ::= { smRunEntry 9 }

  smRunState OBJECT-TYPE
      SYNTAX      INTEGER {
                      initializing(1),
                      executing(2),
                      suspending(3),
                      suspended(4),
                      resuming(5),
                      aborting(6),
                      terminated(7)
                  }
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "The value of this object indicates the script's execution
           status.  If the script has been invoked but has not yet
           begun execution, the value will be `initializing'. If the
           script is running, the value will be `executing'. A script
           which received a request to suspend execution but which
           did not actually suspend execution will be `suspending'.
           A script which has suspended execution will be `suspended'.
           A script which received a request to resume execution but
           which is not yet running is `resuming'. The resuming state
           will finally lead to the `executing' state. A script which
           received a request to abort execution but which is still
           running is `aborting'. A script which stopped execution
           is `terminated'."
      ::= { smRunEntry 10 }




Levi & Schoenwaelder        Standards Track                    [Page 36]

RFC 2592                       Script MIB                       May 1999


  smRunError OBJECT-TYPE
      SYNTAX      SnmpAdminString
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "This  contains a descriptive error message if the script
           terminates in an abnormally. An implementation must store a
           descriptive error message in this object if the script exits
           with the smRunExitCode `genericError'.

           The value of this object is the zero-length string as long
           as the smRunExitCode has the value `noError'"
      DEFVAL { ''H }
      ::= { smRunEntry 11 }

  --
  -- Notifications. The definition of smTraps makes notification
  -- registrations reversible (see STD 58, RFC 2578).
  --

  smTraps OBJECT IDENTIFIER ::= { smNotifications 0 }

  smScriptAbort NOTIFICATION-TYPE
      OBJECTS     { smRunExitCode, smRunEndTime, smRunError }
      STATUS      current
      DESCRIPTION
          "This notification is generated whenever a running script
           terminates with an smRunExitCode unequal to `noError'."
      ::= { smTraps 1 }

  smScriptResult NOTIFICATION-TYPE
      OBJECTS     { smRunResult }
      STATUS      current
      DESCRIPTION
          "This notification can be used by scripts to notify other
           management applications about script results. It can be
           used to notify managers about a script result.

           This notification is not automatically generated by the
           script MIB implementation. It is the responsibility of
           the executing script to emit this notification where it
           is appropriate to do so."
      ::= { smTraps 2 }

  -- conformance information
  smCompliances OBJECT IDENTIFIER ::= { smConformance 1 }
  smGroups      OBJECT IDENTIFIER ::= { smConformance 2 }




Levi & Schoenwaelder        Standards Track                    [Page 37]

RFC 2592                       Script MIB                       May 1999


  -- compliance statements

  smCompliance MODULE-COMPLIANCE
      STATUS      current
      DESCRIPTION
          "The compliance statement for SNMP entities which implement
           the script MIB."
      MODULE      -- this module
      MANDATORY-GROUPS {
              smLanguageGroup, smScriptGroup, smLaunchGroup, smRunGroup
      }
      GROUP   smCodeGroup
      DESCRIPTION
          "The smCodeGroup is mandatory only for those implementations
           that support the downloading of scripts via SNMP."
      OBJECT  smScriptSource
      MIN-ACCESS  read-only
      DESCRIPTION
          "The smScriptSource object is read-only for implementations
           that are not able to download script code from a URL."
      OBJECT smLaunchArgument
      DESCRIPTION
          "A compliant implementation has to support a minimum size
           for smLaunchArgument of 255 octets."
      OBJECT smRunArgument
      DESCRIPTION
          "A compliant implementation has to support a minimum size
           for smRunArgument of 255 octets."
      OBJECT smRunResult
      DESCRIPTION
          "A compliant implementation has to support a minimum size
           for smRunResult of 255 octets."
      OBJECT smRunState
      DESCRIPTION
          "A compliant implementation does not have to support script
           suspension and the smRunState `suspended'. Such an
           implementation will change into the `suspending' state
           when the smRunControl is set to `suspend' and remain in this
           state until smRunControl is set to `resume' or the script
           terminates."
      ::= { smCompliances 1 }

  smLanguageGroup OBJECT-GROUP
      OBJECTS {
          smLangLanguage,
          smLangVersion,
          smLangVendor,
          smLangRevision,



Levi & Schoenwaelder        Standards Track                    [Page 38]

RFC 2592                       Script MIB                       May 1999


          smLangDescr,
          smExtsnExtension,
          smExtsnVersion,
          smExtsnVendor,
          smExtsnRevision,
          smExtsnDescr
      }
      STATUS      current
      DESCRIPTION
          "A collection of objects providing information about the
           capabilities of the scripting engine."
      ::= { smGroups 1 }

  smScriptGroup OBJECT-GROUP
      OBJECTS {
          smScriptDescr,
          smScriptLanguage,
          smScriptSource,
          smScriptAdminStatus,
          smScriptOperStatus,
          smScriptStorageType,
          smScriptRowStatus
      }
      STATUS      current
      DESCRIPTION
          "A collection of objects providing information about
           installed scripts."
      ::= { smGroups 2 }

  smCodeGroup OBJECT-GROUP
      OBJECTS {
          smCodeText,
          smCodeRowStatus
      }
      STATUS      current
      DESCRIPTION
          "A collection of objects used to download or modify scripts
           by using SNMP set requests."
      ::= { smGroups 3 }

  smLaunchGroup OBJECT-GROUP
      OBJECTS {
          smLaunchScriptOwner,
          smLaunchScriptName,
          smLaunchArgument,
          smLaunchMaxRunning,
          smLaunchMaxCompleted,
          smLaunchLifeTime,



Levi & Schoenwaelder        Standards Track                    [Page 39]

RFC 2592                       Script MIB                       May 1999


          smLaunchExpireTime,
          smLaunchStart,
          smLaunchControl,
          smLaunchAdminStatus,
          smLaunchOperStatus,
          smLaunchRunIndexNext,
          smLaunchStorageType,
          smLaunchRowStatus
      }
      STATUS      current
      DESCRIPTION
          "A collection of objects providing information about scripts
           that can be launched."
      ::= { smGroups 4 }

  smRunGroup OBJECT-GROUP
      OBJECTS {
          smRunArgument,
          smRunStartTime,
          smRunEndTime,
          smRunLifeTime,
          smRunExpireTime,
          smRunExitCode,
          smRunResult,
          smRunState,
          smRunControl,
          smRunError
      }
      STATUS      current
      DESCRIPTION
          "A collection of objects providing information about running
           scripts."
      ::= { smGroups 5 }

  smNotificationsGroup NOTIFICATION-GROUP
      NOTIFICATIONS {
          smScriptAbort,
          smScriptResult
      }
      STATUS      current
      DESCRIPTION
          "The notifications emitted by the script MIB."
      ::= { smGroups 6 }

  END






Levi & Schoenwaelder        Standards Track                    [Page 40]

RFC 2592                       Script MIB                       May 1999


7.  Usage Examples

  This section presents some examples that explain how a manager can
  use the Script MIB defined in this memo. The purpose of these
  examples is to explain the steps that are normally used to delegate
  management scripts.

7.1.  Pushing a script via SNMP

  This example explains the steps performed by a manager to push a
  script into a distributed manager.

  1.   The manager first checks the smLanguageTable and the
       smExtensionTable in order to select the appropriate script or
       language.

  2.   The manager creates a row in the smScriptTable by issuing an
       SNMP set-request. The smScriptRowStatus object is set to
       `createAndWait' and the smScriptSource object is set to an empty
       string. The smScriptLanguage object is set to the language in
       which the script was written. The smScriptStorageType object is
       set to `volatile' to indicate that the script will be loaded via
       the smCodeTable.  The smScriptOwner is set to a string which
       identifies the principal who owns the new row. The smScriptName
       defines the administratively assigned unique name for the
       script.

  3.   The manager sets the smScriptRowStatus object to `active' and
       the smScriptAdminStatus object to `editing'.

  4.   The manager pushes the script to the distributed manager by
       issuing a couple of SNMP set-requests to fill the smCodeTable.

  5.   Once the whole script has been transferred, the manager sends a
       set-request to set the smScriptAdminStatus object to `enabled'.
       The Script MIB implementation now makes the script accessible to
       the runtime system. This might include the compilation of the
       script if the language requires a compilation step.

  6.   The manager polls the smScriptOperStatus object until the value
       is either `enabled' or one of the error status codes.  The
       script can only be used if the value of smScriptOperStatus is
       `enabled'.

  7.   If the manager wants to store the script in local non-volatile
       storage, it should send a set-request which changes the
       smScriptStorageType object to `nonVolatile'.




Levi & Schoenwaelder        Standards Track                    [Page 41]

RFC 2592                       Script MIB                       May 1999


7.2.  Pulling a script from a URL

  This example explains the steps performed by a manager to cause a
  distributed manager to pull a script from a URL.

  1.   The manager first checks the smLanguageTable and the
       smExtensionTable in order to select the appropriate script or
       language.

  2.   The manager creates a row in the smScriptTable by issuing an
       SNMP set-request. The smScriptRowStatus object is set to
       `createAndWait' and the smScriptSource object is set to the URL
       which points to the script source. The smScriptLanguage object
       is set to the language in which the script was written. The
       smScriptOwner is set to a string which identifies the principal
       who owns the new row. The smScriptName defines the
       administratively assigned unique name for the script.

  3.   The manager sets the smScriptRowStatus object to `active'.

  4.   The manager sends a set-request to set the smScriptAdminStatus
       object to `enabled'. The Script MIB implementation now makes the
       script accessible to the runtime system. This causes a retrieval
       operation to pull the script from the URL stored in
       smScriptSource. This retrieval operation might be followed by a
       compile operation if the language requires a compilation step.

  5.   The manager polls the smScriptOperStatus object until the value
       is either `enabled' or one of the error status codes.  The
       script can only be used if the value of smScriptOperStatus is
       `enabled'.

  6.   If the manager wants to store the script in local non-volatile
       storage, it should send a set-request which changes the
       smScriptStorageType object to `nonVolatile'.

7.3.  Modifying an existing script

  This section explains how a manager can modify a script by sending
  SNMP set-requests.

  1.   First, the script is de-activated by setting the
       smScriptAdminStatus to `disabled'.

  2.   The manager polls the smScriptOperStatus object until the value
       is `disabled'.





Levi & Schoenwaelder        Standards Track                    [Page 42]

RFC 2592                       Script MIB                       May 1999


  3.   The manager sets smScriptSource to an empty string and
       smScriptAdminStatus to `editing'. This makes the script source
       available in the smCodeTable.

  4.   The manager polls the smScriptOperStatus object until the value
       is `editing'.

  5.   The manager sends SNMP set-requests to modify the script in the
       smCodeTable.

  6.   The manager sends a set-request to set the smScriptAdminStatus
       object to `enabled'. The Script MIB implementation now makes the
       script accessible to the runtime system. This might include the
       compilation of the script if the language requires a compilation
       step.

  7.   The manager polls the smScriptOperStatus object until the value
       is either `enabled' or one of the error status codes.  The
       script can only be used if the value of smScriptOperStatus is
       `enabled'.

7.4.  Removing an existing script

  This section explains how a manager can remove a script from a
  distributed manager.

  1.   First, the manager sets the smScriptAdminStatus to `disabled'.
       This will ensure that no new scripts can be started while
       running scripts finish their execution.

  2.   The manager polls the smScriptOperStatus object until the value
       is `disabled'.

  3.   The manager sends an SNMP set-request to change the
       smScriptRowStatus object to `destroy'. This will remove the row
       and all associated resources from the Script MIB implementation.

7.5.  Creating a launch button

  This section explains how a manager can create a launch button for
  starting a script.

  1.   The manager, who is identified by an smLaunchOwner value, first
       chooses a name for the new row in the smLaunchTable. The manager
       sends an SNMP set-request to set the smLaunchRowStatus object
       for this smLaunchOwner and smLaunchName to `createAndWait'.





Levi & Schoenwaelder        Standards Track                    [Page 43]

RFC 2592                       Script MIB                       May 1999


  2.   The manager fills the new smLaunchTable row with all required
       parameters. The smLaunchScriptOwner and smLaunchScriptName
       values point to the script that should be started from this
       launch button.

  3.   The manager sends a set-request to change smLaunchAdminStatus to
       `enabled' once the new smLaunchTable row is complete.

  4.   The manager polls the smLaunchOperStatus object until the value
       is `enabled'.

7.6.  Launching a script

  This section explains the suggested way to launch a script from a
  given launch button.

  1.   The manager first retrieves the value of smLaunchRunIndexNext
       from the launch button selected to start the script.

  2.   The manager sends an SNMP set-request to set the smLaunchStart
       object to the value obtained in step 1. This will launch the
       script if all necessary pre-conditions are satisfied (see the
       definition of smLaunchStart for more details). The manager can
       also provide the smLaunchArgument in the same set-request that
       is used to start the script. Upon successful start, a new row
       will be created in the smRunTable indexed by smLaunchOwner,
       smLaunchName and the value written to smLaunchStart.

  Note, the first step is not required. A manager can also try to guess
  an unused value for smRunIndex if he wants to start script in a
  single transaction. A manager can also use the special value 0 if he
  does not care about the results produced by the script.

7.7.  Terminating a script

  This section explains two ways to terminate a running script. The
  first approach is as follows:

  1.   The manager sets the smRunControl object of the running script
       or the smLaunchControl object of the launch button used to start
       the running script to `abort'. Setting smLaunchControl will
       abort all running scripts started from the launch button while
       smRunControl will only abort the running script associated with
       the smRunControl instance.







Levi & Schoenwaelder        Standards Track                    [Page 44]

RFC 2592                       Script MIB                       May 1999


  The second way to terminate a script is to set the smRunLifeTime to
  zero which causes the runtime system to terminate the script with a
  `lifeTimeExceeded' exit code:

  1.   The manager changes the value of smRunLifeTime to 0. This causes
       the Script MIB implementation to abort the script because the
       remaining life time has expired.

  Note, changing the smRunLifeTime value can also be used to increase
  the permitted lifetime of a running script. For example, a manager
  can choose to set smRunLifeTime to a small fixed time interval and
  increase the value periodically. This strategy has the nice effect
  that scripts terminate automatically if the manager loses contact
  with the Script MIB engine.

7.8.  Removing a launch button

  This section explains how a manager can remove a launch button from a
  distributed manager.

  1.   First, the manager sets the smLaunchAdminStatus to
       `disabled'. This will ensure that no new scripts can be started
       from this launch button while running script will finish their
       execution.

  2.   The manager polls the smLaunchOperStatus object until the value
       is `disabled'.

  3.   The manager sends an SNMP set-request to change the
       smLaunchRowStatus object to `destroy'. This will remove the row
       and all associated resources from the Script MIB implementation.

8.  VACM Configuration Examples

  This section shows how the view-based access control model defined in
  RFC 2275 [15] can be configured to control access to the script MIB.

8.1.  Sandbox for guests

  The first example demonstrates how to configure VACM to give the
  members of the VACM group "guest" limited access to the script MIB.
  The MIB views defined below give the members of the "guest" group a
  sandbox where they can install and start their own scripts, but not
  access any other scripts maintained by the Script MIB implementation.

     vacmAccessReadView."guest"."".usm.authNoPriv = "guestReadView"
     vacmAccessWriteView."guest"."".usm.authNoPriv = "guestWriteView"




Levi & Schoenwaelder        Standards Track                    [Page 45]

RFC 2592                       Script MIB                       May 1999


  The guestReadView grants read access to the smLangTable, the
  smExtsnTable and to all the table entries owned by "guest":

     guestReadView:
         smLangTable                       (included)
         smExtsnTable                      (included)
         smScriptObjects.*.*.*."guest"     (included)
         smRunObjects.*.*.*."guest"        (included)

  The guestWriteView grants write access to all the table entries owned
  by "guest":

     guestWriteView:
         smScriptObjects.*.*.*."guest"     (included)
         smRunObjects.*.*.*."guest"        (included)

8.2.  Sharing scripts

  This example demonstrates how VACM can be used to share a repository
  of scripts between the members of the "senior" and the members of the
  "junior" VACM group:

     vacmAccessReadView."junior"."".usm.authNoPriv = "juniorReadView"
     vacmAccessWriteView."junior"."".usm.authNoPriv = "juniorWriteView"

     juniorReadView:
         smLangTable                       (included)
         smExtsnTable                      (included)
         smScriptObjects.*.*.*."junior"    (included)
         smRunObjects.*.*.*."junior"       (included)
         smScriptObjects.*.*.*."utils"     (included)

     juniorWriteView:
         smScriptObjects.*.*.*."junior"    (included)
         smRunObjects.*.*.*."junior"       (included)

  The definitions above allow the members of the "junior" VACM group to
  start the scripts owned by "utils" in addition to the script the
  members of the "junior" VACM group installed themself.  This is
  accomplished by giving the members of "junior" read access to scripts
  in "utils".  This allows members of "junior" to create entries in the
  smLauchTable which refer to scripts in "utils", and to launch those
  scripts using these entries in the smLaunchTable.








Levi & Schoenwaelder        Standards Track                    [Page 46]

RFC 2592                       Script MIB                       May 1999


     vacmAccessReadView."senior"."".usm.authNoPriv = "seniorReadView"
     vacmAccessWriteView."senior"."".usm.authNoPriv = "seniorWriteView"

     seniorReadView:
         smLangTable                       (included)
         smExtsnTable                      (included)
         smScriptObjects.*.*.*."senior"    (included)
         smRunObjects.*.*.*."senior"       (included)
         smScriptObjects.*.*.*."utils"     (included)

     seniorWriteView:
         smScriptObjects.*.*.*."senior"    (included)
         smRunObjects.*.*.*."senior"       (included)
         smScriptObjects.*.*.*."utils"     (included)

  The definitions for the members of the "senior" VACM group allow to
  start the scripts owned by "utils" in addition to the script the
  members of the "senior" VACM group installed themself. The third
  write access rule in the seniorWriteView also grants the permission
  to install scripts owned by "utils". The members of the "senior" VACM
  group therefore have the permissions to install and modify scripts
  that can be called by the members of the "junior" VACM group.

8.3.  Emergency scripts


  This example demonstrates how VACM can be used to allow the members
  of the "junior" VACM group to launch scripts that are executed with
  the permissions associated with the "emergency" owner. This works by
  adding the following rules to the juniorReadView and the
  juniorWriteView:

     juniorReadView:
         smScriptObjects.*.*.*."emergency" (included)
         smRunObjects.*.*.*."emergency"    (included)

     juniorWriteView
         smLaunchStart."emergency"         (included)
         smLaunchArgument."emergency"      (included)

  The rules added to the juniorReadView grant read access to the
  scripts, the launch buttons and the results owned by "emergency". The
  rules added to the juniorWriteView grant write permissions to the
  smLaunchStart and smLaunchArgument variables ownded by "emergency".
  Members of the "junior" VACM group can therefore start scripts that
  will execute under the owner "emergency".





Levi & Schoenwaelder        Standards Track                    [Page 47]

RFC 2592                       Script MIB                       May 1999


     seniorReadView:
         smScriptObjects.*.*.*."emergency" (included)
         smRunObjects.*.*.*."emergency"    (included)

     seniorWriteView:
         smScriptObjects.*.*.*."emergency" (included)
         smRunObjects.*.*.*."emergency"    (included)

  The rules added to the seniorReadView and the seniorWriteView will
  give the members of the "senior" VACM group the rights to install
  emergency scripts and to configure appropriate launch buttons.

9.  IANA Considerations

  The Internet Assigned Numbers Authority (IANA) is responsible for
  maintaining a MIB module which provides OID registrations for well-
  known languages. The IANA language registry is intented to reduce
  interoperability problems by providing a single list of well-known
  languages. However, it is of course still possible to register
  languages in private OID spaces. Registering languages in private
  spaces is especially attractive if a language is used for
  experimentation or if a language is only used in environments where
  the distribution of MIB modules with the language registration does
  not cause any maintenance problems.

  Any additions or changes to the list of languages registered via IANA
  require Designated Expert Review as defined in the IANA guidelines
  [20]. The Designated Expert will be selected by the IESG Area
  Director for the IETF Operations and Management Area.

10.  Security Considerations

  This MIB provides the ability to distribute applications written in
  an arbitrary language to remote systems in a network.  The security
  features of the languages available in a particular implementation
  should be taken into consideration when deploying an implementation
  of this MIB.

  To facilitate the provisioning of access control by a security
  administrator using the View-Based Access Control Model (VACM)
  defined in RFC 2275 [15] for tables in which multiple users may need
  to independently create or modify entries, the initial index is used
  as an "owner index". Such an initial index has a syntax of
  SnmpAdminString, and can thus be trivially mapped to a securityName
  or groupName as defined in VACM, in accordance with a security
  policy.





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  All entries in related tables belonging to a particular user will
  have the same value for this initial index.  For a given user's
  entries in a particular table, the object identifiers for the
  information in these entries will have the same subidentifiers
  (except for the "column" subidentifier) up to the end of the encoded
  owner index. To configure VACM to permit access to this portion of
  the table, one would create vacmViewTreeFamilyTable entries with the
  value of vacmViewTreeFamilySubtree including the owner index portion,
  and vacmViewTreeFamilyMask "wildcarding" the column subidentifier.
  More elaborate configurations are possible.

  The VACM access control mechanism described above provides control
  over SNMP access to Script MIB objects. There are a number of other
  access control issues that are outside of the scope of this MIB. For
  example, access control on URLs, especially those that use the file
  scheme, must be realized by the underlying operating system. A
  mapping of the owner index value to a local operating system security
  user identity should be used by an implementation of this MIB to
  control access to operating system resources when resolving URLs or
  executing scripts.

11.  Intellectual Property

  The IETF takes no position regarding the validity or scope of any
  intellectual property or other rights that might be claimed to
  pertain to the implementation or use of the technology described in
  this document or the extent to which any license under such rights
  might or might not be available; neither does it represent that it
  has made any effort to identify any such rights.  Information on the
  IETF's procedures with respect to rights in standards-track and
  standards-related documentation can be found in BCP-11.  Copies of
  claims of rights made available for publication and any assurances of
  licenses to be made available, or the result of an attempt made to
  obtain a general license or permission for the use of such
  proprietary rights by implementors or users of this specification can
  be obtained from the IETF Secretariat.

  The IETF invites any interested party to bring to its attention any
  copyrights, patents or patent applications, or other proprietary
  rights which may cover technology that may be required to practice
  this standard.  Please address the information to the IETF Executive
  Director.

12.  Acknowledgments

  This document was produced by the IETF Distributed Management
  (DISMAN) working group.




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13.  References

  [1]  Harrington, D., Presuhn, R. and B. Wijnen, "An Architecture for
       Describing SNMP Management Frameworks", RFC 2271, January 1998.

  [2]  Rose, M. and K. McCloghrie, "Structure and Identification of
       Management Information for TCP/IP-based Internets", STD 16, RFC
       1155, May 1990.

  [3]  Rose, M. and K. McCloghrie, "Concise MIB Definitions", STD 16,
       RFC 1212, March 1991.

  [4]  Rose, M., "A Convention for Defining Traps for use with the
       SNMP", RFC 1215, March 1991.

  [5]  McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose,
       M. and S. Waldbusser, "Structure of Management Information
       Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.

  [6]  McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose,
       M. and S. Waldbusser, "Textual Conventions for SMIv2", STD 58,
       RFC 2579, April 1999.

  [7]  McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose,
       M. and S. Waldbusser, "Conformance Statements for SMIv2", STD
       58, RFC 2580, April 1999.

  [8]  Case, J., Fedor, M., Schoffstall, M. and J. Davin, "Simple
       Network Management Protocol", STD 15, RFC 1157, May 1990.

  [9]  Case, J., McCloghrie, K., Rose, M. and S. Waldbusser,
       "Introduction to Community-based SNMPv2", RFC 1901, January
       1996.

  [10] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser, "Transport
       Mappings for Version 2 of the Simple Network Management Protocol
       (SNMPv2)", RFC 1906, January 1996.

  [11] Case, J., Harrington D., Presuhn R. and B. Wijnen, "Message
       Processing and Dispatching for the Simple Network Management
       Protocol (SNMP)", RFC 2272, January 1998.

  [12] Blumenthal, U. and B. Wijnen, "User-based Security Model (USM)
       for version 3 of the Simple Network Management Protocol
       (SNMPv3)", RFC 2274, January 1998.






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  [13] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser, "Protocol
       Operations for Version 2 of the Simple Network Management
       Protocol (SNMPv2)", RFC 1905, January 1996.

  [14] Levi, D., Meyer, P. and B. Stewart, "SNMPv3 Applications", RFC
       2273, January 1998.

  [15] Wijnen, B., Presuhn, R. and K. McCloghrie, "View-based Access
       Control Model (VACM) for the Simple Network Management Protocol
       (SNMP)", RFC 2275, January 1998.

  [16] Hovey, R. and S. Bradner, "The Organizations Involved in the
       IETF Standards Process", BCP 11, RFC 2028, October 1996.

  [17] Berners-Lee, T., Fielding, R. and L. Masinter, " Uniform
       Resource Identifiers (URI): Generic Syntax", RFC 2396, August
       1998.

  [18] Postel, J. and J. Reynolds, "File Transfer Protocol", STD 9, RFC
       959, October 1985.

  [19] Fielding, R., Gettys, J., Mogul, J., Frystyk, H. and T.
       Berners-Lee, "Hypertext Transfer Protocol -- HTTP/1.1", RFC
       2068, January 1997.

  [20] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA
       Considerations Section in RFCs", BCP 26, RFC 2434, October 1998.

  [21] Bradner, S., "Key words for use in RFCs to Indicate Requirement
       Levels", BCP 14, RFC 2119, March 1997.





















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14.  Editors' Addresses

  David B. Levi
  Nortel Networks
  4401 Great America Parkway
  Santa Clara, CA 95052-8185
  U.S.A.

  Phone: +1 423 686 0432
  EMail: [email protected]


  Juergen Schoenwaelder
  TU Braunschweig
  Bueltenweg 74/75
  38106 Braunschweig
  Germany

  Phone: +49 531 391-3683
  EMail: [email protected]































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16.  Full Copyright Statement

  Copyright (C) The Internet Society (1999).  All Rights Reserved.

  This document and translations of it may be copied and furnished to
  others, and derivative works that comment on or otherwise explain it
  or assist in its implementation may be prepared, copied, published
  and distributed, in whole or in part, without restriction of any
  kind, provided that the above copyright notice and this paragraph are
  included on all such copies and derivative works.  However, this
  document itself may not be modified in any way, such as by removing
  the copyright notice or references to the Internet Society or other
  Internet organizations, except as needed for the purpose of
  developing Internet standards in which case the procedures for
  copyrights defined in the Internet Standards process must be
  followed, or as required to translate it into languages other than
  English.

  The limited permissions granted above are perpetual and will not be
  revoked by the Internet Society or its successors or assigns.

  This document and the information contained herein is provided on an
  "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
  TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
  BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
  HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
  MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Acknowledgement

  Funding for the RFC Editor function is currently provided by the
  Internet Society.



















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