RFC2592
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.
Contents
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].
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].
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.
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.
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.
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
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.
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.
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:
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.
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.
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.
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.
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.
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)
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.
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
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'.
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.
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.
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.
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"
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
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.
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 }
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.
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. --
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.
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.
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),
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
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
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. --
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
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,
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
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 }
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.
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
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
"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
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
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
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 }
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;
- `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
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 }
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 }
-- 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,
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,
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
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.
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'.
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'.
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'.
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'.
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.
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'.
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'.
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.
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.
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.
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.
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.
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"
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)
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.
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.
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".
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.
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.
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.
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.
[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.
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]
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.
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Acknowledgement
Funding for the RFC Editor function is currently provided by the Internet Society.
