Internet Draft Policy-Based Management MIB Mar 1, 2001
Policy Based Management MIB
draft-ietf-snmpconf-pm-05.txt
March 1, 2001
Steve Waldbusser
Jon Saperia
Thippanna Hongal
Status of this Memo
This document is an Internet-Draft and is in full conformance
with all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet
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Copyright Notice
Copyright (C) The Internet Society (2001). All Rights Reserved.
1. Abstract
This memo defines a portion of the Management Information Base
(MIB) for use with network management protocols in TCP/IP-
based internets. In particular, this MIB defines objects that
enable policy-based configuration management of SNMP
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infrastructures.
2. The SNMP Management Framework
The SNMP Management Framework presently consists of five
major components:
o An overall architecture, described in RFC 2571 [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 2572 [11] and RFC 2574 [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
2573 [14] and the view-based access control mechanism
described in RFC 2575 [15].
A more detailed introduction to the current SNMP Management
Framework can be found in RFC 2570 [18].
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.
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This memo specifies a MIB module that is compliant to the
SMIv2. A MIB conforming to the SMIv1 can be produced
through the appropriate translations. The resulting
translated MIB must be semantically equivalent, except
where objects or events are omitted because no translation
is possible (use of Counter64). Some machine readable
information in SMIv2 will be converted into textual
descriptions in SMIv1 during the translation process.
However, this loss of machine readable information is not
considered to change the semantics of the MIB.
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3. Overview
Large IT organizations have developed management strategies to cope
with the extraordinarily large scale and complexity inherent in
today's networks. In particular, they try to configure the network as
a whole by describing and implementing high-level business policies,
rather than managing device by device, where orders of magnitude more
decisions (and mistakes) may be made.
Following this management practice results in the following benefits:
- Reduced training needs (fewer details to learn)
- Reduced documentation costs (fewer details to document)
- Reduced impact of turnover (less ad-hoc knowledge goes out the door)
- Greater testability (a greater percentage of fielded
configurations may be tested in the lab)
- Higher reliability (combination of factors above)
- Lower cost of changes (changes can be simpler and operate over a
wider extent)
- Lower cost of corporate mergers (less knowledge to transfer; fewer
policies to integrate)
- Lower cost of ownership (combination of factors above)
To illustrate the concept of "business policies", some examples are:
- All routers will run code version 6.2
- On-site contracters will all have special security restrictions on
their ports
- All voice over cable ports in California must provide free local
calling
- Apply special forwarding to all ports whose customers have paid
for premium service.
Each of these policies could represent an action applied to hundreds
of thousands of configuration variables.
In order to automate this practice, customers need software tools that
will implement business policies across their network, as well as
a standard protocol that will ensure that it can be applied to all of
their devices, regardless of the vendor.
This practice is called Policy-Based Network Management. This document
defines standard managed objects for the Simple Network Management
Protocol that are used to distribute policies in a standard form
throughout the network.
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4. Policy-Based Management Architecture
Policy-based network management is the practice of applying management
operations globally on all managed elements that share certain
attributes.
Policies are intended to express a notion of:
if (an element has certain characteristics) then (apply operation to
that element)
Policies take the following normal form:
if (policyFilter) then (policyAction)
A policyFilter is program code which results in a boolean
to determine whether or not an element is a member of a set of
elements upon which an action is to be performed.
A policyAction is an operation performed on an element or a set of
elements.
These policies are most often executed on or near managed devices,
where the elements live (and thus their characteristics may be easily
inspected), and where operations on those elements will be performed.
A management station is responsible for distributing an organization's
policies to all of the managed devices in the infrastructure. The
pmPolicyTable provides managed objects for sending a policy to a
managed device.
In this architecture, an element is a group of related MIB variables
such as all the variables for interface #7. This enables policies to
be expressed more efficiently and concisely. Elements can also model
circuits, CPUs, queues, processes, systems, etc.
The execution model for policies on a managed device is:
foreach element for which policyFilter returns true
execute policyAction on that element
For example:
If (interface is fast ethernet) then (apply full-duplex mode)
If (interface is access) then (apply security filters)
If (gold service paid for on circuit) then (apply special queueing)
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Each unique combination of policy and element is called an execution
context. Within a particular execution context, the phrase "this
element" is often used to refer to the associated element, as most
policy operations will be applied to "this element". The address of
"this element" contains the index of the element, the context the
element was discovered in, and the address of the system on which the
element was discovered. In most circumstances the context and address
will be implicit.
PolicyFilters have the capability of performing comparison operations
on SNMP variables, logical expressions, and other functions. Many
device characteristics are already defined in MIBs and are
easy to include in policyFilter expressions (ifType == ethernet,
frCircuitCommittedBurst < 128K, etc). However, there are
important characteristics that aren't currently in MIB objects, and
worse, it is not current practice to store this information on managed
devices. Therefore, this document defines MIB objects for this
information. To meet today's needs there are three missing areas:
roles, capabilities and time.
Roles
A role is an administratively specified characteristic of a managed
element (for example, an interface). It is a selector for
policies, to determine the applicability of the policy to
a particular managed element.
Some examples of roles are political, financial, legal,
geographical, or architectural characteristics, typically not directly
derivable from information stored on the managed system. For example,
"paid for premium service" or "is plugged into a UPS" are examples of
roles, whereas the "percent utilization of a link" would not be.
Some types of information one would put into a role include:
political - describes the role of a person or group of people, or of
a service that a group of people use. Examples:
executive, sales, outside-contracter, customer.
If (attached user is executive) then (apply higher bandwidth)
If (attached user is outside-contracter) then (restrict access)
financial/legal - describes what financial consideration was
received. Could also include contractual or legal
considerations. Examples:
paid, gold, free, trial, demo, lifeline
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If (gold service paid for) then (apply special queueing)
geographical - describes the location of an element. Examples:
California, Headquarters, insecure conduit.
If (interface leaves the building) then (apply special security)
architectural - describes the network architects "intent" for an
element. For example: backup, trunk.
If (interface is backup) then (set ifAdminStatus = down)
Roles in this model are human defined strings that can be referenced
by policy code. Roles may be assigned to elements by the role group
in this MIB as well as through implementation-dependent
means. Multiple roles may be assigned to each element. Because
policy code can make policy decisions based on the value of any MIB
object, role strings will typically contain information not
accessible in MIB objects.
The roleMatch accessor function allows policy code to make
decisions based on whether or not an element has a particular role
assigned to it.
The role group allows a management station to learn what roles exist
on a managed system. The management station may choose not to
install policies that depend on a role that does not exist on any
elements in the system. The management station can then register for
notifications of new roles. Upon receipt of a pmNewRoleNotification,
it may choose to install new policies that make use of that new
role.
Capabilities
Some actions are inappropriate for certain elements or are simply
unsupported because a capability doesn't exist or because it is
restricted. Policy filters must be able to be defined so that a
policy can be applied only to elements that have the proper
capability. The capabilities table provides MIB objects that
describe the capabilities of the system.
The capMatch accessor function allows policy code to make
decisions based on whether or not an element has certain
capabilities.
The capabilities group allows a management station to learn what
capabilities exist on a managed system. The management station may
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choose not to install policies that depend on a capability that
does not exist on any elements in the system. The management station
can then register for notifications of new capabilities. Upon
receipt of a pmNewCapabilityNotification, it may choose to install
new policies that make use of that new capability.
Time
Managers may wish to define policies that are true for certain
periods of time. This might mean that a policy is installed and is
dormant for a period of time, becomes active, and then later becomes
inactive. Sometimes these time periods will be regular (M-F 9-5) and
sometimes ad-hoc. This MIB provides MIB objects that allow
policies to be dependent on time.
5. Policy Based Management Execution Environment
5.1. Terminology
Run-Time Exception (RTE) - A run-time exception is a fatal
error caused in PolicyScript language processing or in the
processing of accessor functions. If, during the invocation of
a script, a run-time exception occurs, execution of that
script is immediately terminated. If a filter experiences a
run-time exception while processing an element, the element is
not matched by the filter and the associated action will not
be run on that element. A run-time exception can cause an
entry to be added to the pmDebuggingTable and will be
reflected in the pmTrackingPolicyToElementInfo object. The
phrase run-time exception will be commonly abbreviated to RTE.
There are several steps performed in order to execute policies
in this environment:
- Element Discovery
- Element Filtering
- Policy Enforcement
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5.2. Element Discovery
An element is a uniquely addressable entity on a managed
device. Examples of elements include interfaces, circuits,
queues, CPUs, and processes. Sometimes various attributes of
an entity will be described through tables in several standard
and proprietary MIBs - as long as the indexing is consistent
between these tables, the entity can be modeled as 1 element.
For example, the ifTable and the dot3Stats table both contain
attributes of interfaces and share the same index (ifIndex),
therefore they can be modeled in this model as one element
type.
The Element Type Registration table is used for the manager to
learn what element types are being managed by the system and
to register new types if necessary. An element type is
registered by providing the OID of an SNMP object (i.e.,
without the instance). Each SNMP instance that exists under
that object is a distinct element. The address of the element
is the index part of the discovered OID. This address will be
supplied to policy filters and actions so that this code can
inspect and configure the element.
For each element that is discovered, the policy filter is
called with the element address as an argument to see if the
element is a member of the set that the policy acts upon.
Note that agents may automatically configure elements in this
table for frequently used element types (interfaces, circuits,
etc.). In particular, it may configure elements for whom
discovery is optimized in one or both of the following ways:
1. The agent may discover elements by scanning internal data
structures as opposed to issuing local SNMP requests. It is
possible to recreate the exact semantics described in this
table even if local SNMP requests are not issued.
2. The agent may receive asynchronous notification of new
elements (for example, "card inserted") and use that
information to instantly create elements rather than
through polling. A similar feature might be available for
the deletion of elements.
A special element type "0.0" exists. "0.0" represents the
single instance of the system itself and provides an execution
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context for policies to operate on "the system" as well as on
MIB objects modelled as scalars. For example, "0.0" gives an
execution context for policy-based selection of the operating
system code version (likely modeled as a scalar MIB object).
If the agent is discovering elements by polling, it should
check for new elements no less frequently than
pmElementTypeRegMaxLatency would dictate. When an element is
first discovered all policyFilters are run immediately and
policyFilters that match will have the associated policyAction
run immediately. Subsequently, the policyFilter will be run
regularly for the element with no more than
pmPolicyFilterMaxLatency milliseconds elapsing between each
invocation. Note that if an implementation has the ability to
be alerted immediately when a particular type of element is
created, it is urged to discover that type of element in this
fashion rather than through polling, resulting in immediate
configuration of the discovered element.
5.2.1. Implementation Notes
Note that while the external behavior of this registration
process is defined in terms of the walking of MIB tables,
implementation strategies may differ. For example, commonly-
used element types (like interface) may have purpose-built
element discovery capability built-in and advertised to
managers through an entry in the pmElementTypeRegTable.
Before registering an element type, it is the responsibility
of a manager to inspect the table and see if it is already
registered (by the agent or another manager). Note that
entries that differ only in the last OID (which specifies
which object in an entry) are effectively duplicates and
should be treated as such by the manager.
The system which implements the Policy-Based Management MIB
may not have knowledge of the format of object identifiers in
other MIBs. Therefore it is inappropriate for it to check
these OIDs for errors. It is the responsibility of the
management station to register well-formed object-identifiers.
For example, if an extra sub-identifier is supplied when
registering the ifTable, no elements will be discovered.
Similarly, if a sub-identifier is missing, every element will
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be discovered numerous times (once per column) and none of the
element addresses will be well-formed.
5.3. Element Filtering
The first step in executing a policy is to see which elements
match the policy filter. To evaluate a policy, the policy
filter is called once for each element and runs to completion.
The element address is the only state that is passed to the
filter code for each invocation (in particular, except for
state accessible from accessor functions, no state is
remembered from the previous invocation of this element nor
from the previous invocation of the policy filter). If any
run-time exception occurs, the filter will terminate
immediately for this element. If the filter returns non-zero,
the corresponding policy action will be executed for this
element.
If an element matches a filter and it had not matched that
filter the last time it was checked (or it is a newly-
discovered element), the associated policyAction will be
executed immediately. If the element had matched the filter at
the last check, it will remain in the set of elements whose
policyAction will be run within the
policyFilterActionMaxLatency.
5.3.1. Implementation Notes
It is an implementation-dependent matter as to how policy
filters are scheduled. Each filter/element combination is
conceptually its own process and can be scheduled sequentially
or two or more could be run simultaneously.
Policy filters have no side-effects except for changes to the
scratchpad.
5.4. Policy Enforcement
For each element that has returned non-zero from the policy
filter, the corresponding policy action is called. The element
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address is the only state that is passed to the policy action
for each invocation (in particular, except for state
accessible from accessor functions, no state is remembered
from the policy filter evaluation, nor from the previous
filter/action invocation of this element nor from the previous
invocation of the policy filter or action on any other
element). If any run-time exception occurs, the action will
terminate immediately for this element.
5.4.1. Implementation Notes
It is an implementation-dependent matter as to how policy
actions are scheduled. Each filter/element combination is
conceptually its own process and can be scheduled sequentially
or two or more could be run simultaneously.
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6. The PolicyScript Language
Policy filters and policy actions are expressed with the
PolicyScript language. The PolicyScript language is designed
to be a small interpreted language that is simple to
understand and implement; it is designed to be appropriate for
writing small scripts that make up policy filters and actions.
PolicyScript is intended to be familiar to programmers in a
variety of languages, including Perl and C. PolicyScript is
nominally a subset of the C language - however it was
desireable to have access to C++'s operator overloading
(solely to aid in documenting the language - operator
overloading is not a feature of PolicyScript). Therefore,
PolicyScript is defined formally as a subset of the C++
language. A subset was used to provide for easy development of
low-cost interpreters of PolicyScript and to take away
language constructs that are peculiar to the C/C++ languages.
For example, it is expected that both C and Perl programmers
will understand the constructs allowed in PolicyScript.
Some examples of the features that have been removed from the
C/C++ language are: function definitions, pointer variables,
structures, enums, typedefs, floating point and pre-processor
functions (except for comments).
This language is formally defined as a subset of ISO C++ [19],
but only allows those constructs that may be expressed in the
Extended Backus-Naur Form (EBNF) documented here. This is done
because while EBNF doesn't fully specify syntactical rules (it
allows constructs that are invalid) and doesn't specify
semantic rules, it can successfully be used to define the
subset of the language that is required for conformance to
this standard. Unless explicitly described herein, the meaning
of any construct expressed in the EBNF can be found by
reference to the ISO C++ standard.
The use of comments and newlines are allowed and encouraged in
order to promote readability of PolicyScript code. Comments
begin with '/*' and end with '*/' or begin with '//' and go
until the end of the line.
One subset is not expressable in the EBNF syntax: all
variables within a PolicyScript program are within the same
scope.
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PolicyScript code must be expressed in the UTF8 character set.
In the EBNF used here, terminals are character set members
(singly or in a sequence) that are enclosed between two
single-quote characters or described as a phrase between '<'
and '>' characters. Nonterminals are a sequence of letters
and underscore characters. A colon (:) following a
nonterminal introduces its definition, a production. In a
production, a '|' character separates alternatives. The '('
and ')' symbols group the enclosed items. The '[' and ']'
symbols indicate that the enclosed items are optional. The '?'
symbol following an item indicates that the item is optional.
The '*' symbol following an item indicates that the item is
repeated zero, one, or more times. The '+' symbol following an
item indicates that the item is repeated one or more times.
The symbol '--' begins a comment that ends at the end of the
line.
6.1. Formal Definition
The PolicyScript language follows the syntax and semantics of
ISO C++ [19], but is limited to that which that can be
expressed in the EBNF below.
The following keywords are reserved words and cannot be used
in any policy script. This prevents someone from using a word
that is a common keyword in other languages as an identifier
in a program and thus make the meaning of the program
confusing. The reserved words are:
auto, case, char, const, default, do, double, enum,
extern, float, goto, inline, int, long, register, short,
signed, sizeof, static, struct, switch, typedef, union,
unsigned, void, and volatile.
Any syntax error, use of a reserved keyword, reference of an
unknown identifier, improper number or type of function
arguments, exceeding local limitations on string length or
exceeding local limitations on the total amount of storage
used by local variables will cause a RTE.
PolicyScript permits comments using the comment delimiters,
'/*' to '*/' or the start of comment symbol '//'.
-- Lexical Grammar
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letter: '_' | 'a' | 'b' | 'c' | 'd' | 'e' | 'f'
| 'g' | 'h' | 'i' | 'j' | 'k' | 'l' | 'm'
| 'n' | 'o' | 'p' | 'q' | 'r' | 's' | 't'
| 'u' | 'v' | 'w' | 'x' | 'y' | 'z'
| 'A' | 'B' | 'C' | 'D' | 'E' | 'F'
| 'G' | 'H' | 'I' | 'J' | 'K' | 'L' | 'M'
| 'N' | 'O' | 'P' | 'Q' | 'R' | 'S' | 'T'
| 'U' | 'V' | 'W' | 'X' | 'Y' | 'Z'
digit: '0' | '1' | '2' | '3' | '4'
| '5' | '6' | '7' | '8' | '9'
non_zero: '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9'
oct_digit: '0' | '1' | '2' | '3' | '4' | '5' | '6' | '7'
hex_digit: digit | 'a' | 'b' | 'c' | 'd' | 'e' | 'f'
| 'A' | 'B' | 'C' | 'D' | 'E' | 'F'
escape_seq: '\'' | '\"' | '\?' | '\\'
| '\a' | '\b' | '\f' | '\n'
| '\r' | '\t' | '\v'
| '\' oct_digit+ | '\x' hex_digit+
non_quote: Any character in the UTF-8 character set
except single quote ('), double quote ("),
backslash ('\') or newline.
c_char: non_quote | '"' | escape_seq
string_literal: '"' s_char* '"'
s_char: non_quote | ''' | escape_seq
char_constant: ''' c_char '''
decimal_constant: non_zero digit*
octal_constant: '0' oct_digit*
hex_constant: ( '0x' | '0X' ) hex_digit+
integer_constant: decimal_constant | octal_constant | hex_constant
identifier: letter ( letter | digit )*
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-- Phrase Structure Grammar
-- Expressions
primary_expression: identifier | integer_constant
| char_constant | string_literal
| '(' expression ')'
postfix_expression:
primary_expression
| postfix_expression '(' argument_expression_list? ')'
| postfix_expression '++'
| postfix_expression '--'
| postfix_expression '[' expression ']'
argument_expression_list:
assignment_expression
| argument_expression_list ',' assignment_expression
unary_expression: postfix_expression
| unary_op unary_expression
unary_op: '+' | '-' | '~' | '!' | '++' | '--'
binary_expression: unary_expression
| binary_expression binary_op unary_expression
binary_op: '||' | '&&' | '|' | '^' | '&' | '!='
| '==' | '>=' | '<=' | '>' | '<' | '>>'
| '<<' | '-' | '+' | '%' | '/' | '*'
assignment_expression:
binary_expression
| unary_expression assignment_op assignment_expression
assignment_op: '=' | '*=' | '/=' | '%=' | '+=' | '-='
| '<<=' | '>>=' | '&=' | '^=' | '|='
expression: assignment_expression
| expression ',' assignment_expression
-- Declarations
declaration: 'var' declarator_list ';'
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declarator_list: init_declarator
| declarator_list ',' init_declarator
init_declarator: identifier [ '=' assignment_expression ]
-- Statements
statement: declaration
| compound_statement
| expression_statement
| selection_statement
| iteration_statement
| jump_statement
compound_statement: '{' statement* '}'
expression_statement: expression? ';'
selection_statement:
'if' '(' expression ')' statement
| 'if' '(' expression ')' statement 'else' statement
iteration_statement:
'while' '(' expression ')' statement
| 'for' '(' expression? ';' expression? ';' expression? ')'
statement
jump_statement: 'continue' ';'
| 'break' ';'
| 'return' expression? ';'
-- Root production
PolicyScript: statement*
6.2. Variables
To promote shorter scripts and ease in writing scripts,
PolicyScript provides a loosely-typed data class, "var", that
can store both integer and string values. The native C++
types (char, int, etc.) are thus unnecessary and have not been
carried into the subset that comprises this language. The
semantics of the "var" type are modelled after those of
ECMAScript[21].
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For example:
var number = 0, name = "IETF";
This language will be executed in an environment where the
following typedef is declared. (Note that this typedef will
not be visible in the policyFilter or policyAction code.)
typedef ... var;
While this declaration is expressed here as a typedef, the
'typedef' keyword itself is not available to be used inside of
PolicyScript code.
6.2.1. The var class
A value is an entity that takes on one of two types: string or
integer.
The String type is the set of all finite ordered sequences of
zero or more 8-bit unsigned integer values ("elements"). The
string type can store textual data as well as binary data
sequences. Each element is regarded as occupying a position
within the sequence. These positions are indexed with
nonnegative integers. The first element (if any) is at
position 0, the next element (if any) at position 1, and so
on. The length of a string is the number of elements (i.e.,
8-bit values) within it. The empty string has length zero and
therefore contains no elements.
The integer type is the set of all integer values in the range
-9223372036854775808 to 18446744073709551615, plus the value
NaN.
Prior to initialization, a var object has type String and a
length of zero.
The policy script runtime system performs automatic type
conversion as needed. To clarify the semantics of certain
constructs it is useful to define a set of conversion
operators. These operators are not a part of the language;
they are defined here to aid the specification of the
semantics of the language. The conversion operators are
polymorphic; that is, they can accept a value of any standard
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type.
ToInteger
The operator ToInteger converts its argument to a value of
type Integer according to the following table:
Integer The result equals the input argument
(no conversion).
String See grammar and note below
integer_constant The result equals the input argument
(no conversion).
string_literal See grammar and note below
char_constant See grammar and note below
ToInteger Applied to strings
ToInteger applied to the String Type, string_literal and
char_constants applies the following grammar to the input. If
the grammar cannot interpret the string as an expansion of
numeric_string, then the result of ToInteger is NaN. Note that
a numeric_string that is empty or contains only white space is
converted to 0.
-- EBNF for numeric_string
numeric_string : white_space* numeric white_space*
white_space : <TAB> | <SP> | <NBSP> | <FF> | <VT>
| <CR> | <LF> | <LS> | <PS> | <USP>
numeric : signed_decimal | hex_constant | octal_constant
signed_decimal: [ '-' | '+' ] decimal_constant
-- decimal_constant, hex_constant, octal_constant are defined in the
-- PolicyScript EBNF described earlier
ToString
The operator ToString converts its argument to a value of type String
according to the following table:
Integer Return the string containing the decimal
representation of the input argument in
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the form of signed_decimal except that
no leading '+' will be used. If the
value is 'NaN', return the string "NaN".
String Return the input argument (no conversion)
integer_constant Return the string containing the decimal
representation of the input argument in the
form of signed_decimal except that no
leading '+' will be used. If the value is
'NaN', return the string "NaN".
string_literal Return the input argument (no conversion)
char_constant Return the string of length one containing
the value of the input argument.
ToBoolean
The operator ToBoolean converts its argument to a value of type
Integer according to the following table:
Integer The result is 0 if the argument is 0 or
NaN. Otherwise the result is 1.
String The results is 0 if the argument is the
empty string. Otherwise the result is 1.
integer_constant The result is 0 if the argument is 0.
Otherwise the result is 1.
string_literal The results is 0 if the argument is the
empty string. Otherwise the result is 1.
char_constant The result is 1.
Operators
A++, A--, ++A, --A:
A = ToInteger(A); OP;
+A: ToInteger(A);
-A: -1 * ToInteger(A);
~A: ~ToInteger(A);
!A: !ToBoolean(A);
A * B, A - B, A & B, A ^ B , A | B, A << B, A >> B:
ToInteger(A) OP ToInteger(B)
A / B, A % B:
if (ToInteger(B) == 0)
NaN;
else
ToInteger(A) OP ToInteger(B)
A + B:
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if (Type(A) == String || Type(B) == String)
ToString(A) concatenated with ToString(B)
else
A + B
Compound Assignment (op=):
Simply follow rules above. Note that type of LHS may be
changed as a result.
Note that for any operation above, if any operand is 'NaN' or
becomes 'NaN' due to a ToInteger conversion, the result of the
operation will be 'NaN'.
A < B, A > B, A <= B, A >= B, A == B, A != B:
if (Type(A) == String && Type(B) == String)
lexically compare strings with strcmp() logic
else
ToInteger(A) OP ToInteger(B)
A && B:
if (ToBoolean(A))
ToBoolean(B);
else
false;
A || B:
if (ToBoolean(A))
true;
else
ToBoolean(B);
A[B] as a RHS value:
if (Type(A) != String
|| ToInteger(B) == NaN
|| ToInteger(B) >= strlen(A))
RTE, terminate
A[ ToInteger(B) ]
The contents are returned as a string of length one
A[B] = C as a LHS value:
if (Type(A) != String
|| ToInteger(B) == NaN
|| ToInteger(B) >= strlen(A))
RTE, terminate
if (strlen(ToString(C)) == 0)
RTE, terminate
A[ ToInteger(B) ] = First octet of ToString(C)
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Note that this is only applicable in a simple assignment.
6.3. PolicyScript QuickStart Guide
PolicyScript is designed so that programmers fluent in other
languages can quickly begin to write scripts.
One way to become familiar with a language is to see it in
action. The following nonsensical program excercizes most of
the PolicyScript constructs (though it skips some usage
options and many arithmetic operators).
var x, index = 7, str = "Hello World", oid = "ifSpeed.";
x = 0;
while(x < 10){
if (str < "Goodbye") /* string comparison */
continue;
else
break;
x++;
}
if (oidlen(oid) == 10)
oid += "." + index; // append index to oid
for(x = 0; x < 7; x++){
str += "a";
var y = 12;
index = ((x * 7) + y) % 3;
if (str[6] == 'W')
return index;
}
return;
A few examples that are more practical are:
For a filter:
// Return 1 if this is an interface and it is tagged
// with the role "gold"
if (insubtree(elementName(), "ifEntry")
&& roleMatch("gold"))
return 1; // Match
else
return 0;
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A filter/action pair:
First, register the Host Resources MIB hrSWRunEntry as a new element
in the pmElementTypeRegTable. This will cause the policy to run for
every process on the system and $0 will be the process index.
The filter:
// if it's a process and it's an application and it's
// consumed more than 5 minutes of CPU time
if (insubtree(elementName(), "hrSWRunEntry")
&& getvar("hrSWRunType.$0") == 4 // app, not OS or driver
&& getvar("hrSWRunPerfCPU.$0") > 30000) // 300 seconds
return 1;
return 0;
The action:
// Kill it
setvar("hrSWRunStatus.$0", 4, Integer); // invalid(4) kills it
A more substantial action to start an RMON2 host table on interfaces
that match the filter:
var index, pdu;
pdu = newPDU();
// setRowStatus finds an empty row and creates it
if (!(index = setRowStatus("hlHostControlStatus.*", 20)))
return; /* couldn't find a free row */
writeVar(pdu, 0, "hlHostControlDataSource." + index,
"ifIndex." + iv(0), Oid);
writeVar(pdu, 1, "hlHostControlNlMaxDesiredEntries." + index,
1000, Integer);
writeVar(pdu, 2, "hlHostControlAlMaxDesiredEntries." + index,
1000, Integer);
writeVar(pdu, 3, "hlHostControlOwner." + index, "policy", String);
writeVar(pdu, 4, "hlHostControlStatus." + index, 1, Integer);
snmpsend(pdu, 5, OP_SET);
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Because PolicyScript is a least common denominator, it
contains nothing that would astonish programmers familiar with
C, C++, Perl, Tcl, JavaScript or Python. While a new
programmer may attempt to use language constructs that aren't
available in PolicyScript, they should be able to understand
any existing PolicyScript and will likely know how to use
anything that is valid in PolicyScript. The lists below
quickly enumerate the changes of note for programmers coming
some particular languages. These lists won't describe the
unavailable constructs but it is easy to see from the
definition above what is available.
6.3.1. Quickstart for C Programmers
- Character constants (i.e. 'c') are treated as one-character
strings, not integers. So operations like ('M' - 'A') or (x + 'A')
will not perform as expected.
- Accessor functions can change the value of arguments even though
they are not pointers (or called like '&arg').
- All variables are in the same scope
6.3.2. Quickstart for Perl Programmers
- Comments are '/* comment */' and '// till end of line', not '#'
- No need to put a '$' in front of variables
- Strings are compared with ==, <=, < etc. (Details in Sec. 6.2.1)
- Strings are concatenated with '+'. (Details in Sec. 6.2.1)
- No variable substitution in "" strings. '' strings are 1 char only.
- Variables must be declared before use (but no type is necessary)
- All variables are in the same scope
6.3.3. Quickstart for TCL Programmers
- Comments are '/* comment */' and '// till end of line', not '#'
- No need to put a '$' in front of variables
- Function calls are func-name(arg1, arg2, ...)
- Square braces [] don't interpret their contents
- Double quotes "" surround a string but no substitutions are
performed ("" is like { } in TCL )
- Statements are terminated by a semicolon;
- Instead of "Set a b", use "b = a;"
- Strings are concatenated with '+'. (Details in Sec. 6.2.1)
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- All variables are in the same scope
6.3.4. Quickstart for Python Programmers
- Comments are '/* comment */' and '// till end of line', not '#'
- Single quotes can be used only for single-character strings ('a')
- Indentation doesn't matter. Braces {} define blocks.
- Variables must be declared before use (but no type is necessary)
- The expression for if and while is always surrounded by
parenthesis, like "if (x < 5)".
- 'for' syntax is "for(expression; expression; expression)" (see EBNF).
- All variables are in the same scope
6.3.5. Quickstart for JavaScript/ECMAScript/JScript
Programmers
- Variables must be declared before use.
- Accessor functions can change the value of arguments
- All variables are in the same scope
7. Address of `this element'
PolicyScript code needs a convenient way to get the components
of the index for "this element" so that they can perform SNMP
operations on it or on related elements.
Two mechanisms are provided.
1. For all oid input parameters to all SNMP Accessor Functions (but
not oid utility functions), the token "$n" ('$' followed by an
integer between 0 and 99) can be used in place of any decimal
sub-identifier. This token is expanded by the agent at execution
time to contain the n'th subid of the index for the current
element. For example, if the element is interface #7, and the
objectIdentifier is "1.3.6.1.2.1.2.2.1.3.$0", it will be expanded
to "1.3.6.1.2.1.2.2.1.3.7".
It is an RTE if a token is specified that is beyond the length of
the index for the current element.
2. The ic() and iv() functions allow access to the components of the
index for "this element". ic() takes no argument and returns the
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number index components exist. iv() takes an integer argument
specifying which component of the index (numbered starting at 0)
and returns an integer containing the value of the n'th
subidentifier. Refer to the accessor functions section for the
complete definition of ic() and iv().
For example, if "this element" is frCircuitDLCI.5.57
(ifIndex = 5, DLCI = 57)
then ic() returns 2
iv(0) returns 5
iv(1) returns 57
This is helpful when wishing to address a related element.
Extending the previous example, to find the port speed of the port
the circuit (above) runs over:
portSpeed = getvar("ifSpeed." + iv(0));
8. Accessor Functions
Accessor functions are built-in functions available primarily
to provide access to information on the local system or to
more efficiently manipulate this information. A group of
functions is organized into a library, the unit of conformance
for function implementation. In order to claim conformance to
a library, an implementation must implement all functions in a
library to the specifications of the library.
In order for a management station or a filter or action to
understand if a certain library of functions is implemented,
each library will have a registration OID that it registers in
this MIB's capabilities table. Thus, conformance to a library
can be tested with the capMatch library function (in the base
library) or by inspecting the pmCapabilitiesType objects in
the pmCapabilitiesTable.
9. Base Accessor Function Library
A standard base library of accessor functions is available to
all systems that implement this specification. This library is
known by the capability OID of:
pmBaseFunctionLibrary ::= { policyMgt pmConformance pmGroups 4 }
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This library contains four types of functions:
- SNMP Accessor functions
- Policy Configuration Accessor functions
- Utility functions
- Library Functions
Note that in the descriptions of these functions below, the
function prototype describes the type of argument expected.
Even though variables are not declared with a particular type,
their contents be as appropriate for each function argument.
If the type is variable, the keyword 'var' will be used. If
only a string is appropriate, the keyword 'string' will be
used. If only an integer is appropriate, the keyword 'integer'
will be used.
In the function prototype, if the '&' character precedes the
identifier for an argument, that argument may be modified by
the function (e.g., "integer &result, ...)"). Arguments
without the '&' character cannot be modified by the function.
9.1. SNMP Accessor Functions
Two sets of SNMP Accessor functions are available with
different situations in mind:
- Convenience SNMP Functions
In an effort to keep simple things simple, these functions are
easy to use and promote easy to understand code. These functions
will suffice for the majority of situations where a single
variable is referenced and the desired error recovery is to simply
(and immediately) give up (and move to the next policy-element
combination). In more complex cases, the General SNMP Functions
can be used at the cost of several times the code complexity.
The convenience SNMP functions are getvar, exists,
setvar, setRowStatus, and searchcolumn.
- General SNMP Functions
The General SNMP functions allow nearly any legal SNMP Message to
be generated, including those with multiple varbinds, getNext
operations, notifications, and messages with explicit addressing
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or security specifications.
The general SNMP functions are writeVar, readVar, and snmpsend.
9.1.1. Form of SNMP Values Many of the accessor functions
have input or output parameters that may be one of the many
SMI data types. The actual type is not encoded in the value,
but rather is specified elsewhere, possibly by nature of the
context in which it is used. The exact usage for input and
output is:
Any Integer value
(INTEGER, Integer32, Counter32, Counter64, Gauge32, Unsigned32,
TimeTicks, Counter64):
On input:
An Integer or a String that can be successfully coerced to an
Integer with the ToInteger() function. It is an RTE
ifToInteger().
On output:
An Integer containing the returned value.
Octet String
On input:
Either a String or an Integer. If an Integer, it will be coerced
to a String with the ToString() function. This string will be
used as an unencoded representation of the octet string value.
On output:
A String containing the unencoded value of the octet string.
Object Identifier
On input and on output:
A String containing a decimal ascii encoded object identifier
of the following form:
oid: subid [ '.' subid ]* [ '.' ]
subid: '0' | decimal_constant
It is an RTE if an Object Identifier argument is not in the form
above. Note that a trailing '.' is acceptable and will simply be
ignored.
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Note that ascii descriptors (e.g. "ifIndex") are never used in
these encodings "over the wire". They are never returned from
accessor functions nor are they ever accepted by them. NMS user
interfaces are encouraged to allow humans to view object
identifiers with ascii descriptors, but they must translate those
descriptors to dotted-decimal format before sending them in MIB
objects to policy agents.
9.1.2. Convenience SNMP Functions
9.1.2.1. getvar()
The getvar() function is used to retrieve the value of an SNMP
MIB instance.
string getvar(string oid)
'Oid' is a string containing an ASCII dotted-decimal
representation of an object identifier
(e.g. "1.3.6.1.2.1.1.1.0").
The agent will retrieve the instance in the same SNMP context
in which the element resides. Note that no actual SNMP PDU
needs to be generated and parsed when the policy MIB module
resides on the same system as the managed elements.
It is an RTE if the queried object identifier value does not
exist.
This function returns a string containing the returned value,
encoded according to the returned type.
It is recommended that NMS user interfaces display and allow
input of MIB object names by their descriptor values followed
by the index in dotted-decimal form (e.g., "ifType.7").
9.1.2.2. exists()
The exists() function is used to verify the existence of an
SNMP MIB instance.
integer exists(string oid)
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'oid' is a string containing an ASCII dotted-decimal
representation of an object identifier
(e.g. "1.3.6.1.2.1.1.1.0").
The agent will retrieve the instance in the same SNMP context
in which the element resides. Note that no actual SNMP PDU
needs to be generated and parsed when the policy MIB module
resides on the same system as the managed elements.
This function returns the value 1 if the SNMP instance exists
and 0 if it doesn't exist.
It is recommended that NMS user interfaces display and allow
input of MIB object names by their descriptor values followed
by the index in dotted-decimal form (e.g., "ifType.7").
9.1.2.3. setvar()
The setvar() function is used to set a MIB instance to a
certain value. The setvar() function is only valid in
policyActions. If when executing a policyFilter, the agent
encounters a call to the setvar() function, it is an RTE.
integer setvar(string oid, var value, integer type)
'oid' is a string containing an ASCII dotted-decimal
representation of an object identifier
(e.g. "1.3.6.1.2.1.1.1.0").
'value' is a string encoded in the format appropriate to
the 'type' parameter. The agent will set the variable
specified by 'oid' to the value specified by 'value'.
'type' will be the type of the 'value'' parameter and will
be set to one of the values for DataType Constants.
The agent will set the instance in the same SNMP context
in which the element resides. Note that no actual SNMP PDU
needs to be generated and parsed when the policy MIB module
resides on the same system as the managed elements.
If the set encounters any error, 0 is returned. If sucessful,
1 is returned.
It is recommended that NMS user interfaces display and allow
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input of MIB object names by their descriptor values followed
by the index in dotted-decimal form (e.g., "ifType.7").
9.1.2.4. searchcolumn()
integer searchcolumn(string columnoid, string &oid,
var pattern, integer mode)
searchcolumn performs an SNMP walk on a portion of the MIB
searching for objects with values equal to the `value'
parameter.
'columnoid' constrains the search to only those variables that
share the same OID prefix (i.e. are beneath it in the OID
tree).
A getnext packet will be sent requesting the object identifier
'oid'. If 'oid' is an empty string, the value of 'columnoid'
will be sent.
The value returned in each response packet will be transformed
to a string representation of the value of the returned
variable. The string representation of the value will be
formed by putting the value in the form dictated by the "Form
of SNMP Values" rules, and then performing the ToString()
function on this value, forming 'SearchString'.
The 'mode' value controls what type of match to perform on
this value. There are 6 possibilities for mode:
mode Search Action
0 Case sensitive exact match of 'pattern'
and 'SearchString'
1 Case insensitive exact match of 'pattern'
and 'SearchString'
2 Case sensitive substring match, finding
'pattern' in 'SearchString'
3 Case isensitive substring match, finding
'pattern' in 'SearchString'
4 Case sensitive regular expression match,
searching 'SearchString' for the regular
expression given in 'pattern'.
5 Case isensitive regular expression match,
searching 'SearchString' for the regular
expression given in 'pattern'.
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searchcolumn uses the POSIX extended regular expressions
defined in POSIX 1003.2. If the `case` argument is 0, the
search will be case insensitive, otherwise it will be case
sensitive.
If a match is found, 'oid' is set to the oid of the matched
value and 1 is returned. If the search traverses beyond
columnoid or returns an error without finding a match, zero is
returned and oid isn't modified.
To find the first match, the caller should set 'oid' to the
empty string. To find additional matches, subsequent calls to
searchcolumn sould have 'oid' set to the oid of the last
match, an operation than searchcolumn performs automatically.
For example:
To find an ethernet interface
oid = "";
searchcolumn("ifType", oid, "6", Integer);
This sends a getnext request for ifType and continues to walk
the tree until a value matching 6 is found or a variable
returns that is not in the 'ifType' subtree.
To find the next ethernet interface, assuming interface #3
was discovered to be the first:
oid = "ifType.3";
searchcolumn("ifType", oid, "6", Integer);
In a loop, this looks simply like:
oid = "";
while(searchcolumn("ifType", oid, "6", Integer)){
/* Do something with oid */
}
Note that in the preceeding examples, "ifType" is used as a
notational convenience and the actual code downloaded to the
policy MIB agent must use the string "1.3.6.1.2.1.2.2.1.3" as
there may be no MIB compiler (or MIB) available on the policy
MIB agent.
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9.1.2.5. setRowStatus()
integer setRowStatus(string oid, integer maxTries [, integer seed])
setRowStatus is used to automate the process of finding an
unused row in a read-create table that uses RowStatus.
'oid' is a string containing an ASCII dotted-decimal
representation of an object identifier, with one of
the subids replaced with a '*' character
(e.g. "1.3.6.1.3.1.99.1.2.1.9.*"). 'oid' must reference an
'instance' of the RowStatus object and the '*' must replace
any integer index item that may be set to some random value.
setRowStatus will come up with a number for the selected index
item and will attempt to create the instance with the
createAndWait state. If the attempt fails, it will retry with
a different random index value. It will attempt this no more
than 'maxTries' times.
If the optional 'seed' argument is present, the initial index
will be set to 'seed'. Otherwise it will be random.
setRowStatus returns the successful integer value for the
index. If unsuccessful after 'maxTries' or if more than one
'*' is in oid, -1 will be returned.
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9.1.2.6. counterRate()
When a policy wishes to make a decision based on the rate of a
counter, it faces a couple of problems:
1. It may need to run every X minutes, but need to make
decisions on rates calculated over at least Y minutes
where Y > X. This would require the complexity of managing
a queue of old counter values.
2. The policy script has no control over exactly when it
will run
The counterRate() function is designed to easily surmount
these problems.
integer counterRate(string oid, int minInterval [, integer 64bit])
counterRate retrieves the variable specified by oid once per
invocation. It keeps track of timestamped values retrieved on
previous invocations by this execution context so that it can
calculate a rate over a longer period than since the last
invocation.
'oid' is the object identifier that will be retrieved.
A previously-saved value of the same object identifier that is
older than 'minInterval' seconds old will be subtracted from
the newly-retrieved value, yielding a delta. This delta will
be divided by the number of seconds elapsed between the two
retrievals and the integer-valued result will be returned.
If there was no previously-saved retrieval older than
'minInterval' seconds, then -1 will be returned.
The delta calculation will allow for 32-bit counter semantics
if it encounters rollover between the two retrievals unless
the the optional argument '64bit' is present and equal to 1,
in which case it will allow for 64-bit counter semantics.
The implementation will need to store a number of timestamped
counter values. The implementation is free to throw away
old values as long as it retains at least one value that is
older than minInterval seconds.
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9.1.2.7. counter32Delta()
If a (single) counter overflow occurs between successive
retrievals of a Counter32 object, the delta can still be
retrieved accurately but it has to be done consistent with 32
bit unsigned rollover semantics. This function is useful to
simplify that process in an environment where all counters are
64 bits.
Example:
var counter, lastcounter, delta;
counter = getvar("ifInOctets.$0");
if (getScratchpad(PolicyElement, "inOctets", lastcounter)){
// if returns 0, no value was stored, so punt to next iteration
delta = counter32Delta(lastcounter, counter);
}
setScratchpad(PolicyElement, "inOctets", counter);
/*
* delta now contains the 32bit delta of ifInoctets since the last
* iteration.
*/
integer counter32Delta(integer old, integer new)
counter32Delta returns the delta between 'new' and 'old'
compensating for the potential 32-bit unsigned rollover of the
counter between the sampling of 'new' and 'old'.
9.1.3. General SNMP Functions
It is desireable for a general SNMP interface have the ability
to perform SNMP operations on multiple variables at once and
for it to allow multiple varbind lists to exist at once. The
newPdu, readVar and writeVar functions exist in order to
provide these facilities in a language without pointers,
arrays and memory allocators.
newPDU is called to allocate a PDU and return an integer
handle to it. Since PDUs are automatically freed when the
script exits and because they can be reused during execution,
there is no freePDU().
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readVar and writeVar access a variable length varbindlist for
a PDU. The PDU handle and the index of the variable within
that PDU are specified in every readVar and writeVar
operation. Once a PDU has been fully specified by one or more
calls to writeVar, it is passed to snmpsend (by referencing
the PDU handle) and the number of varbinds to be included in
the operation. When a response is returned, the contents of
the response are in the same varbindlist (i.e. the same PDU
handle is used) and may be read by one or more calls to
readVar.
Varbinds in this data store are created automatically whenever
they are written by any writeVar, readVar, or snmpsend
operation. It is an RTE to read a varbind that has not been
previously written.
For example:
var pdu = newPDU();
writeVar(pdu, 0, "sysDescr.0", ...);
writeVar(pdu, 1, "sysOID.0", ...);
writeVar(pdu, 2, "ifNumber.0", ...);
if (snmpsend(pdu, 3, Get, ...))
return;
readVar(pdu, 0, iKnowItsSysDescr, iKnowItsaString, value);
readVar(pdu, 1, ...)
readVar(pdy, 2, ...)
...
or,
var pdu = newPDU();
writeVar(pdu, 0, "ifIndex", ...);
writeVar(pdu, 1, "ifType", ...);
while(!done){
if (snmpsend(pdu, 2, Getnext, ...))
continue;
readVar(pdu, 0, oid1, ...);
readVar(pdu, 1, oid2, ...);
/* leave OIDs alone, now varbindlist #0 is set up for next step
in table walk. */
if (oidncmp(oid1, "ifIndex", oidlen("ifIndex")))
done = 0;
...
}
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Note that in the preceeding examples, descriptors such as
ifType and sysDescr are used in object identifiers solely as a
notational convenience and the actual code downloaded to the
policy MIB agent must use a dotted decimal notation only as
there may be no MIB compiler (or MIB) available on the policy
MIB agent.
It is suggested that implementations limit the total number of
PDUs per invocation to protect other script invocations from a
malfunctioning script (e.g. a script that calls newPDU() in a
loop). To be conformant to this specification, implementations
must allow each policy script invocation to allocate at least
5 varbindlists with at least 32 varbinds per list.
9.1.3.1. newPDU()
integer newPDU()
newPDU will allocate a new PDU and return a handle to the
PDU. If no PDU could be allocated, -1 will be returned.
9.1.3.2. writeVar()
writeVar(integer pdu, integer varBindIndex,
string oid, var value, integer type)
writeVar will store 'oid', 'value' and 'type' in
the specified varbind.
'pdu' is the handle to a PDU allocated by newPDU().
'varbindIndex' is a non-negative integer that identifies the
varbind within the specified PDU modified by this call. The
first varbind is number 0.
'oid' is a string containing an ASCII dotted-decimal
representation of an object identifier
(e.g. "1.3.6.1.2.1.1.1.0").
'value' is the value to be stored, of a type appropriate to the
'type' parameter.
'type' will be the type of the value parameter and will be set
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to one of the values for DataType Constants.
9.1.3.3. readVar()
readVar(integer pdu, integer varBindIndex,
string &oid, var &value, integer &type)
readVar will retrieve the oid, the value and it's type
from the specified varbind.
'pdu' is the handle to a PDU allocated by newPDU().
'varbindIndex' is a non-negative integer that identifies the
varbind within the specified PDU read by this call. The
first varbind is number 0.
The object identifier value of the referenced varbind will be
copied into the 'oid' parameter, formatted in an ASCII
dotted-decimal representation (e.g. "1.3.6.1.2.1.1.1.0").
'value' is the value retrieved, of a type appropriate to the
'type' parameter.
'type' is the type of the value parameter and will be set to
one of the values for DataType Constants.
If 'pdu' doesn't reference a valid PDU or 'varBindIndex'
doesn't reference a valid varbind, the function returns
without modifying 'oid', 'value' or 'type'.
9.1.3.4. snmpsend()
integer snmpsend(integer pdu, integer numVarbinds, integer opcode
[, string context] [, string tagvalue] )
snmpsend will perform an SNMP operation using the specified
varbindlist. Note that no actual SNMP PDU needs to be
generated and parsed when the policy MIB module
resides on the same system as the managed elements.
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If the optional argument context is provided, the SNMP
operation is performed on the indicated SNMP context.
If the optional argument tagvalue is provided, the context
argument must be provided as well. In this case, an SNMP PDU
will be generated and sent to the management targets
referenced by tagvalue and using the security information
referenced by tagvalue. tagValue is a string in the form
described by the SnmpTagValue TEXTUAL_CONVENTION in [14].
The results of the operation will be placed in the same
varbindList. If an error occurred, the varbindlist will remain
unmodified except for the following:
1) If the response PDU had a nonzero error-index, the
varbind specified by the error-index will have its type
field replaced with associated error-status constant.
2) If the response PDU contained varbinds with exceptions,
the type field of those varbinds will be replaced with
the appropriate exception (Nosuchobject,
NosuchInstance, or Endofmibview).
3) If the error-status was zero and there were no
exceptions, the varbindlist will remain unmodified. (some
examples of situations where this will apply are timeout
and authentication failure).
This function returns zero unless an error occurs in which
case it returns the proper SNMP Error Constant.
'pdu' is the handle to a PDU allocated by newPDU().
'numVarbinds' is a integer greater than zero that specified
which varbinds in the varbindList will be used in this
operation. The first N varbinds in the varbindList are used.
'opcode' is the type of SNMP operation to perform and must be
one of the values for SNMP Operation Constants.
9.2. Constants
The following constants are defined for use in all SNMP
Accessor Functions. Policy code will be executed in an
environment where the following constants are declared. (Note
that these constant declarations will not be visible in the
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policyFilter or policyAction code.)
While these declarations are expressed here as C 'const's, the
'const' construct itself is not available to be used inside of
policy code.
-- Datatype Constants
const int Integer = 1;
const int String = 2;
const int Oid = 3;
const int Integer32 = 4;
const int Ipaddress = 5;
const int Counter32 = 6;
const int Gauge32 = 7;
const int Unsigned32 = 8;
const int Timeticks = 9;
const int Opaque = 10;
const int Counter64 = 11;
-- SNMP Error Constants
const int Nosuchobject = 21;
const int Nosuchinstance = 22;
const int Endofmibview = 23;
const int Noerror = 24;
const int Toobig = 25;
const int Nosuchname = 26;
const int Badvalue = 27;
const int Readonly = 28;
const int Generr = 29;
const int Noaccess = 30;
const int Wrongtype = 31;
const int Wronglength = 32;
const int Wrongencoding = 33;
const int Wrongvalue = 34;
const int Nocreation = 35;
const int Inconsistentvalue = 36;
const int Resourceunavailable = 37;
const int Commitfailed = 38;
const int Undofailed = 39;
const int Authorizationerror = 40;
const int Notwritable = 41;
const int Badparameter = 42;
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const int Toolong = 43;
const int Parseerror = 44;
const int Authfailure = 45;
const int Timeout = 46;
-- SNMP Operation Constants
const int Get = 0;
const int Getnext = 1;
const int Set = 3;
const int Trap = 4;
const int Inform = 6;
const int V2trap = 7;
9.3. Policy Configuration Accessor Functions
Policy Configuration Accessor Functions provide access to
information specifically related to the execution of policies.
9.3.1. roleMatch()
The roleMatch() function is used to check to see if an element
has been assigned a particular role.
integer roleMatch(string roleString [, string element])
Argument 'roleString' is a string. The optional argument
'element' contains the OID address of an element, defaulting
to the current element if this argument is not supplied.
If roleString exactly matches (content and length) any role
assigned to the specified element, the function returns 1. If
no roles match, the function returns 0.
9.3.2. capMatch()
The capMatch() function is used to check to see if an element
has a certain capability.
integer capMatch(string capOid[ , string element])
Argument 'capability' is a string containing a
ASCII dotted-decimal representation of an object identifier
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that describes a capability as would be found in the
pmCapabilitiesTable. The optional argument 'element'
contains the OID address of an element, defaulting to the
current element if this argument is not supplied.
If the specified element has the capability described by
capString, this function returns 1, otherwise it returns 0.
9.3.3. elementName()
The elementName() function is used to determine what the
current element is and can be used to provide information
about the type of element as well as how it is indexed.
string elementName()
elementName returns a string containing an ASCII
dotted-decimal representation of an object identifier
(e.g. 1.3.6.1.2.1.1.1.0). This object identifier identifies an
instance of a MIB object that is an attribute of this element.
9.3.4. ic()
The ic() and iv() functions provide convenient access to the
components of the index for "this element". Typical uses will
be in creating the index to other, related elements.
integer ic()
ic() returns an integer count of the number index subidentifiers
exist in the index for "this element".
9.3.5. iv()
The ic() and iv() functions provide convenient access to the
components of the index for "this element". Typical uses will
be in creating the index to other, related elements.
integer iv(integer n)
iv() returns the value of the n'th subidentifier in the index
for 'this element". The first subidentifier is indexed at
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0. It is an RTE if 'n' specifies a subidentifier beyond the
last subidentifier.
9.3.6. setScratchpad()
setScratchpad(integer scope, string varName, string value)
Every maxLatency time period, every policy runs once for each
element. When the setScratchpad function executes, it stores a
value that can be retrieved even after this policy execution
code exits. This allows sharing of data between a filter and
an action, two filters executing on different elements, or
even different policies altogether. The value of 'scope'
controls which policy/element combinations can retrieve this
'varName'/'value' pair. The options for 'scope' are:
Global
The 'varName'/'value' combination will be available in the
filter or action of any policy while executing on any
element.
Policy
The 'varName'/'value' combination will be available in any
future execution of the filter or action of the current
policy (regardless of what element the policy is executing
on). If a policy is ever deleted or its filter or action
code is modified, all values in its 'Policy' scope will be
deleted.
PolicyElement
The 'varName'/'value' combination will be available in
future executions of the filter or action of the current
policy but only when the policy is executing on the
current element. If a policy is ever deleted or its filter
or action code is modified, all values in its
'PolicyElement' scope will be deleted.
'varName' is a string used to identify the value. Subsequent
retrievals of the same 'varName' in the proper scope will
return the value stored. Note that the namespace for 'varName'
is distinct for each scope. 'varName' is case sensitive.
'value' is a string containing the value to be stored.
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ToString(value) is called on this argument to convert it
to a string before storage.
Note that there may be implementation-specific limits on the
number of scratchpad variables that can be allocated. The
limit of unique scratchpad variables may be different for each
scope.
Contents of the scratchpad are erased on reboot.
9.3.7. getScratchpad()
integer getScratchpad(integer scope, string varName,
string &value)
The getScratchpad function allows the retrieval of values that
were stored previously in this execution context or in
other execution contexts. The value of 'scope' controls which
execution contexts can pass a value to this execution context.
Refer to the definition of setScratchpad to see which values
of 'scope' can pass a value to which execution contexts.
'varName' is a string used to identify the value. Subsequent
retrievals of the same 'varName' in the proper scope will return
the value stored. Note that the namespace for varName is
distinct for each scope. As a result, getScratchpad cannot
force access to a variable in an inaccessible scope - it can
only retrieve variables by referencing the proper scope in
which they were set. 'varName' is case sensitive.
On successful return, 'value' will be set to the value that was
previously stored, otherwise 'value' will not be modified.
This function returns 1 if a value was previously stored and 0
otherwise.
Scratchpad Usage Examples
Policy Element Action
A ifIndex.1 setScratchpad("foo", Global, "55")
A ifIndex.1 getScratchpad("foo", Global, val) == 55
A ifIndex.2 getScratchpad("foo", Global, val) == 55
B ifIndex.2 getScratchpad("foo", Global, val) == 55
B ifIndex.2 setScratchpad("foo", Global, "16")
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A ifIndex.1 getScratchpad("foo", Global, val) == 16
Policy Element Action
A ifIndex.1 setScratchpad("bar", Policy, "75")
A ifIndex.1 getScratchpad("bar", Policy, val) == 75
A ifIndex.2 getScratchpad("bar", Policy, val) == 75
B ifIndex.1 getScratchpad("bar", Policy, val) not found
B ifIndex.1 setScratchpad("bar", Policy, "20")
A ifIndex.2 getScratchpad("bar", Policy, val) == 75
B ifIndex.2 getScratchpad("bar", Policy, val) == 20
Policy Element Action
A ifIndex.1 setScratchpad("baz", PolicyElement, "43")
A ifIndex.1 getScratchpad("baz", PolicyElement, val) == 43
A ifIndex.2 getScratchpad("baz", PolicyElement, val) not found
B ifIndex.1 getScratchpad("baz", PolicyElement, val) not found
A ifIndex.2 setScratchpad("baz", PolicyElement, "54")
B ifIndex.1 setScratchpad("baz", PolicyElement, "65")
A ifIndex.1 getScratchpad("baz", PolicyElement, val) == 43
A ifIndex.2 getScratchpad("baz", PolicyElement, val) == 54
B ifIndex.1 getScratchpad("baz", PolicyElement, val) == 65
Policy Element Action
A ifIndex.1 setScratchpad("foo", PolicyElement, "11")
A ifIndex.1 setScratchpad("foo", Global, "22")
A ifIndex.1 getScratchpad("foo", PolicyElement, val) == 11
A ifIndex.1 getScratchpad("foo", Global, val) == 22
9.3.8. Constants
The following constants are defined for use for the scratchpad
functions. Policy code will be executed in an environment
where the following constants are declared. (Note that these
constant declarations will not be visible in the policyFilter
or policyAction MIB objects.)
While these declarations are expressed here as C 'const's, the
'const' construct itself is not available to be used inside of
policy code.
-- Scratchpad Constants
const int Global = 0;
const int Policy = 1;
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const int PolicyElement = 2;
9.3.9. signalException()
The signalException() function is used to by the script to
indicate to a management station that it is experiencing
abnormal behavior. signalException() turns on the
filterUserSignal(3) or actionUserSignal(5) bit in the
associated pmTrackingPolicyToElementInfo object (subsequent
calls to signalError() have no additional effect). This bit is
initially cleared at the beginning of each execution, so if
upon a subsequent execution, a script no longer calls this
function, the bit will be cleared.
signalException()
The signalException function takes no arguments and returns no
value.
9.3.10. getParameters()
From time to time, policy scripts may desire one or more
parameters (e.g., site-specific constants). These parameters
may be installed with the script in this object and are
accessible to the script via the getParameters() accessor
function. If it is necessary for multiple parameters to be
passed to the script, the script can choose whatever
encoding/delimiting mechanism is most appropriate.
string getParameters()
The getParameters function takes no arguments. It returns a
string containing the value of the pmPolicyParameters object
for the running policy.
9.4. Utility Accessor Functions
Utility Accessor Functions are provided to enable more
efficient use of the other accessor functions.
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9.4.1. regexp()
integer regexp(string pattern, string str,
integer case [, string &match])
regexp searches 'str' for matches to the regular expression
given in `pattern`. regexp uses the POSIX extended regular
expressions defined in POSIX 1003.2.
If the `case` argument is 0, the search will be case
insensitive, otherwise it will be case sensitive.
If a match is found, 1 is returned, otherwise 0 is returned.
If the optional argument 'match' is provided and a match is
found, the text of the first match will be copied to
'match'. If no match is found it will be unchanged.
9.4.2. regexp_replace()
string regexp_replace(string pattern, string replacement,
string str, integer case)
regexp_replace searches 'str' for matches to the regular expression
given in `pattern`, replacing the matched text with
'replacement'. regexp_replace uses the POSIX extended regular
expressions defined in POSIX 1003.2.
If the `case` argument is 0, the search will be case
insensitive, otherwise it will be case sensitive.
The modified string is returned (which could be the same as
the original string if no matches were found).
9.4.3. oidlen()
integer oidlen(string oid)
oidlen returns the number of subidentifiers in 'oid'. 'oid' is
a string containing an ASCII dotted-decimal representation of
an object identifier (e.g. "1.3.6.1.2.1.1.1.0").
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9.4.4. oidncmp()
integer oidncmp(string oid1, string oid2, integer n)
Arguments 'oid1' and 'oid2' are strings containing
ASCII dotted-decimal representations of object identifiers
(e.g. "1.3.6.1.2.1.1.1.0").
oidcmp compares the first 'n' subidentifiers of 'oid1' and
'oid2' and returns -1 if 'oid1' is less than 'oid2', 0 if they
are equal, and 1 if 'oid1' is greater than 'oid2'.
9.4.5. insubtree()
integer insubtree(string oid, string prefix)
Arguments 'oid' and 'prefix' are strings containing
ASCII dotted-decimal representations of object identifiers
(e.g. "1.3.6.1.2.1.1.1.0").
insubtree returns 1 if every subidentifier in 'prefix' equals
the corresponding subidentifier in 'oid', otherwise it returns
0. The is equivalent to oidncmp(oid1, prefix, oidlen(prefix))
is is provided because this is an idiom and because it avoids
evaluating 'prefix' twice if is an expression.
9.4.6. subid()
integer subid(string oid, integer n)
subid returns the value of the 'n'th (starting at zero)
subidentifier of 'oid'. 'oid' is a string containing an ASCII
dotted-decimal representation of an object identifier
(e.g. "1.3.6.1.2.1.1.1.0").
If 'n' specifies a subidentifier beyond the length of 'oid', a
value of -1 is returned.
9.4.7. subidwrite()
integer subidwrite(string oid, integer n, integer subid)
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subidwrite sets the value of the 'n'th (starting at zero)
subidentifier of 'oid' to `subid'. 'oid' is a string
containing an ASCII dotted-decimal representation of an object
identifier (e.g. "1.3.6.1.2.1.1.1.0").
If 'n' specifies a subidentifier beyond the length of 'oid',
a value of -1 is returned. Note that appending subidentifiers
can be accomplished with the string concatenation '+'
operator.
9.4.8. oidsplice()
string oidsplice(string oid1, integer offset, integer len, string oid2)
oidsplice replaces 'len' subidentifiers in 'oid1' with all of
the subidentifiers from 'oid2', starting at 'offset' in 'oid1'
(the first subidentifier is at offset 0). The oid length will
be extended if necessary if 'offset' + 'len' extends beyond
the end of 'oid1'. The resulting oid is returned.
9.4.9. parseindex()
Parseindex is provided to make it easy to pull index values
from OIDs into variables.
var parseindex(string oid, integer &index, integer type,
integer len)
parseindex pulls values from the instance identification
portion of 'oid', encoded as per Section 7.7 "Mapping of the
INDEX clause" of the SMIv2[5].
'oid' is the oid to be parsed.
'index' describes which subid to begin parsing at. 'index'
will be modified to indicate the subid after the last one
parsed (even if this points past the last subid). The first
subid is index 0. If any error occurs, 'index' will set to -1
on return. If the input index refers past the end of the oid,
'index' will be set to -1 on return.
If 'type' is Integer, 'len' will not be consulted. The return
value is the integer value of the next subid.
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If 'type' is String and 'len' is greater than zero, 'len'
subids will be parsed. For each subid parsed, the chr() value
of the subid will be appended to the returned string. If any
subid is greater than 255, the 'index' argument will be set to
-1 on return and an empty string will be returned. If there
are fewer than 'len' subids left in 'oid', 'index' will be
set to -1 on return but a string will be returned containing a
character for each subid that was left.
If 'type' is String and 'len' is zero, the next subid will be
parsed to find 'N', the length of the string. Then this many
subids will be parsed. For each subid parsed, the chr() value
of the subid will be appended to the returned string. If any
subid is greater than 255, the 'index' argument will be set to
-1 on return and an empty string will be returned. If there
are fewer than 'N' subids left in 'oid', 'index' will be set
to -1 on return but a string will be returned containing a
character for each subid that was left.
If 'type' is String and 'len' is -1, subids will be parsed
until the end of 'oid'. For each subid parsed, the chr()
value of the subid will be appended to the returned string. If
any subid is greater than 255, the 'index' argument will be
set to -1 on return and an empty string will be returned.
If 'type' is Oid and 'len' is greater than zero, 'len' subids
will be parsed. For each subid parsed, the decimal-encoded
value of the subid will be appended to the returned string,
with a '.' character appended between each output subid but
not after the last subid. If there are fewer than 'len' subids
left in 'oid', 'index' will be set to -1 on return but a
string will be returned containing an encoding for each subid
that was left.
If 'type' is Oid and 'len' is zero, the next subid will be
parsed to find 'N', the number of subids to parse. For each
subid parsed, the decimal-encoded value of the subid will be
appended to the returned string, with a '.' character appended
between each output subid but not after the last subid. If
there are fewer than 'N' subids left in 'oid', 'index' will be
set to -1 on return but a string will be returned containing
an encoding for each subid that was left.
If 'type' is Oid and 'len' is -1, subids will be parsed until
the end of 'oid'. For each subid parsed, the decimal-encoded
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value of the subid will be appended to the returned string,
with a '.' character appended between each output subid but
not after the last subid.
9.4.10. stringToDotted()
stringToDotted() is provided to encode strings suitable for
the index portion of an oid or to convert the binary encoding
of an ip address to a dotted-decimal encoding.
string stringToDotted(string value)
If 'value' is the zero length string, the zero length string
is returned.
The decimal encoding of the first byte of 'value' is appended
to the output string. Then for each additional byte in
'value', a '.' is appended to the output string followed by
the decimal encoding of the additional byte.
9.4.11. Integer()
integer Integer(var input)
Integer converts 'input' into an integer by using the rules
specified for ToInteger(), returning the integer-typed
results.
9.4.12. String()
string String(var input)
String converts 'input' into a string by using the rules
specified for ToString(), returning the string-typed
results.
9.4.13. Type()
string Type(var variable)
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Type returns the type of its argument as either the string
'String' or the string 'Integer'.
9.4.14. chr()
string chr(integer utf8)
Returns a one-character string containing the character
specified by the UTF8 code contained in 'utf8'. Note that a
property of UTF8 is that 7-bit ASCII characters are
represented by the same UTF8 code-points as their ascii
equalivents.
9.4.15. ord()
integer ord(string str)
Returns the UTF8 code-point value of the first character of
'str'. This function complements chr(). Note that a property of
UTF8 is that 7-bit ASCII characters are represented by the
same UTF8 code-points as their ascii equalivents.
9.4.16. substr()
string substr(string &str, integer offset,
integer len [, string replacement])
Extracts a substring out of 'str' and returns it. The first
octet is at offset 0. If offset is negative, the returned
string starts that far from the end of 'str'. If 'len' is
positive, the returned string contains up to 'len' octets,
up to the end of the string. If 'len' is omitted, the returned
string includes everything to the end of 'str'. If 'len' is
negative, abs(len) octets are left off the end of the
string.
If you specify a substring that is partly outside the string,
the part within the string is returned. If the substring is
totally outside the string, a zero-length string is produced.
If the optional replacement argument is included, 'str' is
modified. 'offset' and 'len' act as above to select a range of
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octets in 'str'. These octets are replaced with
octets from 'replacement'. If the replacement string is
shorter or longer than the number of octets selected,
'str' will shrink or grow respectively.
9.5. Library Accessor Functions
The following standard library accessor functions are
provided:
strncmp()
strncasecmp()
strlen()
random()
sprintf()
sscanf()
10. Schedule Table
This table is an adapted form of the schedTable, originally
published in RFC 2591 [20].
The policy schedule table allows control over when a policy
will be active based on the time of day. A policy that is
controlled by a schedule immediately executes its policy
filter (and conditionally the policyAction) when the schedule
becomes active, periodically re-executing these scripts as
appropriate until the schedule becomes inactive. If a policy
is associated with multiple schedules, it is considered active
at any moment at least one of the schedules is active. A
policy that is not controlled by a schedule will be
continuously active.
The policy schedule table provides for scheduling of policies
periodically or at specified dates and times. Policies are
activated at the beginning of each scheduled duration and
remain active until the end of the duration.
Schedules can be enabled or disabled by modifying the
pmSchedAdminStatus object. This allows pre-configured
schedules to exist which are activated or deactivated by other
management functions.
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The term `scheduler' is used throughout this memo to refer to
the entity which implements the schedule table and which
activates and deactivates policies at the specified points in
time.
10.1. Periodic Schedules
Periodic schedules are based on fixed time periods between the
initiation of scheduled activations. Periodic schedules are
defined by specifying the number of seconds between two
initiations. If the duration of a schedule causes it to remain
active at the next initiation, it will remain active, with no
interruption, into the next scheduled duration.
10.2. Calendar Schedules
Calendar schedules allow policies to be activated at specified
days of the week and days of the month. Calendar schedules are
therefore aware of the notion of months, days, weekdays, hours
and minutes.
It is possible to specify multiple values for each calendar
item. This provides a mechanism for defining complex
schedules. For example, a schedule could be defined which is
active the entire workday each weekday.
Months, days and weekdays are specified using the objects
pmSchedMonth, pmSchedDay and pmSchedWeekDay of type BITS.
Setting multiple bits to one in these objects causes an OR
operation. For example, setting the bits monday(1) and
friday(5) in pmSchedWeekDay restricts the schedule to Mondays
and Fridays.
The bit fields for pmSchedMonth, pmSchedDay and pmSchedWeekDay
are combined using an AND operation. For example, setting the
bits june(5) and july(6) in pmSchedMonth and combining it with
the bits monday(1) and friday(5) set in pmSchedWeekDay will
result in a schedule which is restricted to every Monday and
Friday in the months June and July. Wildcarding of calendar
items is achieved by setting all bits to one.
It is possible to define calendar schedules that will never
trigger cause a policy to be activated. For example, one can
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define a calendar schedule which should be active on February
31st. Schedules like this will simply be ignored by the
scheduler.
Finally, calendar schedules are always expressed in local
time. A scalar, pmSchedLocalTime is provided so that a manager
can retrieve the notion of local time and the offset to GMT
time.
10.3. One-shot Schedules
One-shot Schedules are similar to calendar schedules. The
difference between a calendar schedule and a one-shot schedule
is that a one-shot schedule will automatically disable itself
the first time it moves from the active state to the inactive
state.
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11. Definitions
POLICY-MANAGEMENT-MIB DEFINITIONS ::= BEGIN
IMPORTS
MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE,
Counter32, Integer32, Gauge32, Unsigned32,
experimental FROM SNMPv2-SMI
RowStatus, RowPointer, TEXTUAL-CONVENTION,
DateAndTime, StorageType, TDomain, TAddress FROM SNMPv2-TC
MODULE-COMPLIANCE, OBJECT-GROUP,
NOTIFICATION-GROUP FROM SNMPv2-CONF
SnmpAdminString FROM SNMP-FRAMEWORK-MIB;
-- Policy-Based Management MIB
policyMgt MODULE-IDENTITY
LAST-UPDATED "200103011500Z" -- March 1, 2001
ORGANIZATION "IETF SNMP Configuration Working Group"
CONTACT-INFO
"
Steve Waldbusser
Phone: +1-650-948-6500
Fax: +1-650-745-0671
Email: waldbusser@nextbeacon.com
Jon Saperia
JDS Consulting, Inc.
174 Chapman St.
Watertown MA 02472-3063
USA
Phone: +1-617-744-1079
Fax: +1-617-249-0874
Email: saperia@jdscons.com
Thippanna Hongal
Riverstone Networks, Inc.
5200 Great America Parkway
Santa Clara, CA, 95054
USA
Phone: +1-408-878-6562
Fax: +1-408-878-6501
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Email: hongal@riverstonenet.com"
DESCRIPTION
"The MIB module for rule-based configuration of SNMP
infrastructures."
REVISION "200103011500Z" -- March 1, 2001
DESCRIPTION
"The original version of this MIB, published as RFCXXXX."
::= { experimental 107 }
UTF8String ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"An octet string containing information typically in
human-readable form.
To facilitate internationalization, this
information is represented using the ISO/IEC
IS 10646-1 character set, encoded as an octet
string using the UTF-8 transformation format
described in [RFC2279].
Since additional code points are added by
amendments to the 10646 standard from time
to time, implementations must be prepared to
encounter any code point from 0x00000000 to
0x7fffffff. Byte sequences that do not
correspond to the valid UTF-8 encoding of a
code point or are outside this range are
prohibited.
The use of control codes should be avoided.
When it is necessary to represent a newline,
the control code sequence CR LF should be used.
For code points not directly supported by user
interface hardware or software, an alternative
means of entry and display, such as hexadecimal,
may be provided.
For information encoded in 7-bit US-ASCII,
the UTF-8 encoding is identical to the
US-ASCII encoding.
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UTF-8 may require multiple bytes to represent a
single character / code point; thus the length
of this object in octets may be different from
the number of characters encoded. Similarly,
size constraints refer to the number of encoded
octets, not the number of characters represented
by an encoding.
Note that when this TC is used for an object that
is used or envisioned to be used as an index, then
a SIZE restriction MUST be specified so that the
number of sub-identifiers for any object instance
does not exceed the limit of 128, as defined by
[RFC1905].
Note that the size of an UTF8String object is
measured in octets, not characters."
SYNTAX OCTET STRING
-- The policy group
pmPolicyTable OBJECT-TYPE
SYNTAX SEQUENCE OF PmPolicyEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The policy table. A policy is a pairing of a
policyFilter and a policyAction which is used to apply the
action to a selected set of elements."
::= { policyMgt 1 }
pmPolicyEntry OBJECT-TYPE
SYNTAX PmPolicyEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the policy table."
INDEX { pmPolicyIndex }
::= { pmPolicyTable 1 }
PmPolicyEntry ::= SEQUENCE {
pmPolicyIndex Unsigned32,
pmPolicyGroup UTF8String,
pmPolicyPrecedence Unsigned32,
pmPolicySchedule Unsigned32,
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pmPolicyFilter Unsigned32,
pmPolicyAction Unsigned32,
pmPolicyParameters OCTET STRING,
pmPolicyFilterMaxLatency Unsigned32,
pmPolicyActionMaxLatency Unsigned32,
pmPolicyMaxIterations Unsigned32,
pmPolicyDescription UTF8String,
pmPolicyMatches Gauge32,
pmPolicyAbnormalTerminations Gauge32,
pmPolicyExecutionErrors Counter32,
pmPolicyDebugging INTEGER,
pmPolicyAdminStatus INTEGER,
pmPolicyStorageType StorageType,
pmPolicyRowStatus RowStatus
}
pmPolicyIndex OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A unique index for this policy entry."
::= { pmPolicyEntry 1 }
pmPolicyGroup OBJECT-TYPE
SYNTAX UTF8String (SIZE (0..32))
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"An administratively assigned string that is used to group
policies. Of all policies in the same group, only one will
have its policyAction active on an element at any instance."
::= { pmPolicyEntry 2 }
pmPolicyPrecedence OBJECT-TYPE
SYNTAX Unsigned32 (0..65535)
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"If while checking to see which policy filters match an
element, 2 or more policies in the same group match the same
element, the pmPolicyPrecedence object provides the rule to
arbitrate which single policy action will be executed on this
element. Of policies in the same group, only the matching
policy with the highest precedence value will have its policy
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action periodically executed on this element. In the case
where multiple policies share the highest value, it is an
implementation-dependent matter as to which single policy
action will be chosen."
::= { pmPolicyEntry 3 }
pmPolicySchedule OBJECT-TYPE
SYNTAX Unsigned32 (1..65535)
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"If this entry contains a valid pmSchedGroupIndex value, this
policy will be activated as specified by the associated schedule
entries. Whenever any schedule in the group is active, this
policy will be active.
If the value of this object is 0, this policy is always
active."
::= { pmPolicyEntry 4 }
pmPolicyFilter OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"A pointer to the row or rows in the pmPolicyCodeTable that
contain the filter code for this policy. When a policy entry
is created, an unused pmPolicyCodeIndex value will be
assigned to this object.
A policy filter is one or more PolicyScript statements
which results in a boolean value that represents whether or
not an element is a member of a set of elements upon which an
action is to be performed.
Filter evaluation stops immediately when any run-time
exception is detected and the policyAction is not executed.
The policyFilter is evaluated for various elements. Any
element for which the policyFilter returns any nonzero value
will match the filter and will have the associated
policyAction executed on that element.
If the filter object is empty (contains no code) or otherwise
does not return a value, the element will not be matched.
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When executing this filter, if SNMP requests are made to the
local system, access to objects is under the security
credentials of the the requester who modified the most
recently modified pmPolicyCodeEntry associated
with either the pmPolicyFilter value or pmPolicyAction
value. In other words, modification of any part of a policy's
filter or action will change the credentials stored for the
policy.
These credentials are the input parameters for
isAccessAllowed from the Architecture for Describing SNMP
Management Frameworks[1]."
::= { pmPolicyEntry 5 }
pmPolicyAction OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"A pointer to the row or rows in the pmPolicyCodeTable that
contain the action code for this policy. When a policy entry
is created, an unused pmPolicyCodeIndex value will be
assigned to this object.
A pmPolicyAction is an operation performed on a set of
elements.
Action evaluation stops immediately when any run-time
exception is detected.
When executing this action, if SNMP requests are made to the
local system, access to objects is under the security
credentials of the the requester who modified the most
recently modified pmPolicyCodeEntry associated
with either the pmPolicyFilter value or pmPolicyAction
value. In other words, modification of any part of a policy's
filter or action will change the credentials stored for the
policy.
These credentials are the input parameters for
isAccessAllowed from the Architecture for Describing SNMP
Management Frameworks[1]."
::= { pmPolicyEntry 6 }
pmPolicyParameters OBJECT-TYPE
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SYNTAX OCTET STRING
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"From time to time, policy scripts may desire one or more
parameters (e.g., site-specific constants). These parameters
may be installed with the script in this object and are
accessible to the script via the getParameters() accessor
function. If it is necessary for multiple parameters to be
passed to the script, the script can choose whatever
encoding/deliminiting mechanism is most appropriate."
::= { pmPolicyEntry 7 }
pmPolicyFilterMaxLatency OBJECT-TYPE
SYNTAX Unsigned32
UNITS "milliseconds"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"Every element under the control of this agent is
re-checked periodically to see if it is under control of this
policy by re-running the filter for this policy.
This object lets the manager control the maximum amount of
time that may pass before an element is re-checked.
In other words, in any given interval of this duration, all
elements must be re-checked. Note that it is an
implementation-dependent matter as to how the policy agent
schedules the checking of various elements within this
interval."
::= { pmPolicyEntry 8 }
pmPolicyActionMaxLatency OBJECT-TYPE
SYNTAX Unsigned32
UNITS "milliseconds"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"Every element that matches this policy's filter and is
therefore under control of this policy will have this policy's
action executed periodically to ensure that the element
remains in the state dictated by the policy.
This object lets the manager control the maximum amount of
time that may pass before an element has the action run on
it.
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In other words, in any given interval of this duration, all
elements under control of this policy must have the action run
on them. Note that it is an implementation-dependent matter as
to how the policy agent schedules the policy action on various
elements within this interval."
::= { pmPolicyEntry 9 }
pmPolicyMaxIterations OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"If a filter or action script iterates in loops too many
time in one invocation, it may be considered by the execution
environment to be in an infinite loop or otherwise not acting
as intended and may be terminated by the execution
environment. The execution environment will count the
cumulative number of times all 'for' or 'while' loops iterated
and will apply a threshold to determine when to terminate the
script. It is an implementation-dependent manner as to what
threshold the execution environment uses, but the value of
this object SHOULD be the basis for choosing the threshold for
each script. The value of this object represents a
policy-specific threshold and can be tuned for policies of
varying workloads. If this value is zero, no
threshold will be enforced except for any
implementation-dependent maximum.
Note that the filter and action invocations are tracked
separately."
::= { pmPolicyEntry 10 }
pmPolicyDescription OBJECT-TYPE
SYNTAX UTF8String
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"A description of this rule and its significance, typically
provided by a human."
::= { pmPolicyEntry 11 }
pmPolicyMatches OBJECT-TYPE
SYNTAX Gauge32
UNITS "elements"
MAX-ACCESS read-only
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STATUS current
DESCRIPTION
"The number of elements that, in their most recent execution
of the associated filter, were matched by the filter."
::= { pmPolicyEntry 12 }
pmPolicyAbnormalTerminations OBJECT-TYPE
SYNTAX Gauge32
UNITS "elements"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of elements that, in their most recent execution
of the associated filter or action, have experienced a
run-time exception and terminated abnormally. Note that if a
policy was experiencing a run-time exception while processing
a particular element but on a subsequent invocation it runs
normally, this number can decline."
::= { pmPolicyEntry 13 }
pmPolicyExecutionErrors OBJECT-TYPE
SYNTAX Counter32
UNITS "errors"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of times that execution of this policy's
filter or action has been terminated due to run-time
exceptions."
::= { pmPolicyEntry 14 }
pmPolicyDebugging OBJECT-TYPE
SYNTAX INTEGER {
off(0),
on(1)
}
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of debugging for this policy. If this is turned
on(1), log entries will be created in the pmDebuggingTable
for each run-time exception that is experienced by this
policy."
DEFVAL { off }
::= { pmPolicyEntry 15 }
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pmPolicyAdminStatus OBJECT-TYPE
SYNTAX INTEGER {
inactive(0),
active(1),
activeAutoRemove(2)
}
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The admin status of this policy.
The policy will be runnable only if the associated
pmPolicyRowStatus is set to active(1) or activeAutoRemove(2)
and this object is set to active(1).
If this object is set to activeAutoRemove(2), the next time
the associated schedule moves from the active state to the
inactive state, this policy will immediately be deleted,
including any associated entries in the pmPolicyCodeTable.
[Note to reader: This object exists because a row cannot sit
for extended periods of time with it's rowstatus set to
inactive (it is subject to garbage collection. This object
allows policies to be downloaded but not run except at the
convenience of the management station.]"
::= { pmPolicyEntry 16 }
pmPolicyStorageType OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This object defines whether this policy and any associated
entries in the pmPolicyCodeTable are kept in volatile storage
and lost upon reboot or if this row is backed up by
non-volatile or permanent storage."
::= { pmPolicyEntry 17 }
pmPolicyRowStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The row status of this pmPolicyEntry.
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The status may not be set to active if any of the related
entries in the pmPolicyCode table do not have a status of
active and if any of the objects in this row are not set to
valid values.
If this row is deleted, any associated entries in the
pmPolicyCodeTable will be deleted as well."
::= { pmPolicyEntry 18 }
-- Policy Code Table
pmPolicyCodeTable OBJECT-TYPE
SYNTAX SEQUENCE OF PmPolicyCodeEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The pmPolicyCodeTable stores the code for policy filters and
actions."
::= { policyMgt 2 }
pmPolicyCodeEntry OBJECT-TYPE
SYNTAX PmPolicyCodeEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the policy code table."
INDEX { pmPolicyCodeProgramIndex, pmPolicyCodeSegment }
::= { pmPolicyCodeTable 1 }
PmPolicyCodeEntry ::= SEQUENCE {
pmPolicyCodeProgramIndex Unsigned32,
pmPolicyCodeSegment Unsigned32,
pmPolicyCodeText UTF8String,
pmPolicyCodeStatus RowStatus
}
pmPolicyCodeProgramIndex OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A unique index for each policy filter or action. The code
for each such filter or action may be composed of multiple
entries in this table if the code cannot fit in one entry.
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Values of pmPolicyCodeProgramIndex may not be used unless
they have previously been assigned in the
pmPolicyFilterProgramIndex or pmPolicyActionProgramIndex
objects."
::= { pmPolicyCodeEntry 1 }
pmPolicyCodeSegment OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A unique index for each segment of a policy filter or
action.
When a policy filter or action spans multiple entries in this
table, the code of that policy starts from the
lowest-numbered segment and continues with increasing segment
values until ending with the highest-numbered segment."
::= { pmPolicyCodeEntry 2 }
pmPolicyCodeText OBJECT-TYPE
SYNTAX UTF8String (SIZE (1..1024))
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"A segment of policy code (filter or action). Lengthy Policy
filters or actions may be stored in multiple segments in this
table that share the same value of pmPolicyCodeProgramIndex.
When multiple segments are used, it is recommended that each
segment be as large as practical.
Entries in this table are associated with policies by values
of the pmPolicyFilterProgramIndex and
pmPolicyActionProgramIndex objects. If the status of the
related policy is active, then this object may not be
modified."
::= { pmPolicyCodeEntry 3 }
pmPolicyCodeStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this code entry.
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Entries in this table are associated with policies by values
of the pmPolicyFilterProgramIndex and
pmPolicyActionProgramIndex objects. If the status of the
related policy is active, then entries in this table may not
be created or deleted."
::= { pmPolicyCodeEntry 4 }
-- Element Type Registration Table
-- The Element Type Registration table is used for the manager to
-- learn what element types are being managed by the system and to
-- register new types if necessary. An element type is registered by
-- providing the OID of an SNMP object (i.e., without the
-- instance). Each SNMP instance that exists under that object is a
-- distinct element. The address of the element is the index part of
-- the discovered OID. This address will be supplied to policy filters
-- and actions so that this code can inspect and configure the
-- element.
pmElementTypeRegTable OBJECT-TYPE
SYNTAX SEQUENCE OF PmElementTypeRegEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A registration table for element types managed by this
system.
Before registering an element type, it is the responsibility
of a manager to inspect the table and see if it is already
registered (by the agent or another manager). Note that
entries that differ only in the last OID (which specifies
which object in an entry) are effectively duplicates and
should be treated as such by the manager.
Note that agents may automatically configure elements in this
table for frequently used element types (interfaces, circuits,
etc.). In particular, it may configure elements for whom
discovery is optimized in one or both of the following ways:
1. The agent may discover elements by scanning internal data
structures as opposed to issuing local SNMP requests. It is
possible to recreate the exact semantics described in this
table even if local SNMP requests are not issued.
2. The agent may receive asynchronous notification of new
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elements (for example, 'card inserted') and use that
information to instantly create elements rather than
through polling. A similar feature might be available for
the deletion of elements."
::= { policyMgt 3 }
pmElementTypeRegEntry OBJECT-TYPE
SYNTAX PmElementTypeRegEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A registration of an element type."
INDEX { pmElementTypeRegIndex }
::= { pmElementTypeRegTable 1 }
PmElementTypeRegEntry ::= SEQUENCE {
pmElementTypeRegIndex Unsigned32,
pmElementTypeRegOIDPrefix OBJECT IDENTIFIER,
pmElementTypeRegMaxLatency Unsigned32,
pmElementTypeRegName UTF8String,
pmElementTypeRegStorageType StorageType,
pmElementTypeRegRowStatus RowStatus
}
pmElementTypeRegIndex OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A unique index for this entry."
::= { pmElementTypeRegEntry 1 }
pmElementTypeRegOIDPrefix OBJECT-TYPE
SYNTAX OBJECT IDENTIFIER
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"An OBJECT IDENTIFIER subtree under which all instances of
this element type may be found.
This OBJECT IDENTIFIER should be specified up to, but not
including, any index objects. The agent will discover all
instances in the system that are members of the specified
subtree. Each instance in this subtree becomes a distinct
element. The agent will then execute policy filters (and
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potentially policy actions) for each instance discovered.
The index of each discovered instance becomes the address of
the associated element. For each element, the address of 'this
element' will be passed to each invocation of the policy
filter. This is derived by taking the last N sub-identifiers
from the discovered instance, where N is:
X = number of sub-identifiers in pmElementTypeRegOIDPrefix
Y = number of sub-identifiers in discovered instance
N = Y - X
A special OBJECT IDENTIFIER '0.0' can be written to this
object. '0.0' represents the single instance of the system
itself and provides an execution context for policies to
operate on 'the system' as well as on MIB objects modelled
as scalars. For example, '0.0' gives an execution context for
policy-based selection of the operating system code version
(likely modeled as a scalar MIB object).
When a policy is invoked on behalf of a '0.0' entry in this
table, the element name will be '0.0' and there is no address
of 'this element' (in other words it has zero length)."
::= { pmElementTypeRegEntry 2 }
pmElementTypeRegMaxLatency OBJECT-TYPE
SYNTAX Unsigned32
UNITS "milliseconds"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The PM agent is responsible for discovering new elements of
types that are registered. This object lets the manager
control the maximum amount of time that may pass between the
time an element is created and when it is discovered.
In other words, in any given interval of this duration, all
new elements must be discovered. Note that it is an
implementation-dependent matter as to how the policy agent
schedules the checking of various elements within this
interval."
::= { pmElementTypeRegEntry 3 }
pmElementTypeRegName OBJECT-TYPE
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SYNTAX UTF8String (SIZE (0..32))
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"A descriptive label for this registered type."
::= { pmElementTypeRegEntry 4 }
pmElementTypeRegStorageType OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This object defines whether this row is kept
in volatile storage and lost upon reboot or if this row is
backed up by non-volatile or permanent storage."
::= { pmElementTypeRegEntry 5 }
pmElementTypeRegRowStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this registration entry."
::= { pmElementTypeRegEntry 6 }
-- Role Table
-- The pmRoleTable is a read-create table that organizes role
-- strings sorted by element. This table is used to create and modify
-- role strings and their associations as well as to allow a
-- management station to learn about the existence of roles and their
-- associations.
--
-- It is the responsibility of the agent to keep track of any
-- re-indexing of the underlying SNMP elements and to continue to
-- associate role strings with the element with which they were
-- initially configured.
--
-- Policy MIB agents that have elements in multiple local contexts
-- need to allow some roles to be assigned to elements in particular
-- contexts. This is particularly true when some elements have the
-- same names in different contexts and the context is required to
-- disambiguate them. In those situations, a value for the
-- pmRoleContextName may be provided. When a pmRoleContextName value
-- is not provided, the assignment is to the element in the default
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-- context.
--
-- Policy MIB agents that discover elements on other systems and
-- execute policies on their behalf need to have access to role
-- information for these remote elements. In such situations, role
-- assignements for other systems can be stored in this table by
-- providing values for the pmRoleTDomain and pmRoleTAddress
-- parameters.
--
-- For example:
-- Example:
-- element role context address #comment
-- ifindex.1 gold local, default context
-- ifindex.2 gold local, default context
-- repeaterid.1 foo rptr1 local, rptr1 context
-- repeaterid.1 bar rptr2 local, rptr2 context
-- ifindex.1 gold "" 10.1.2.3 different system
-- ifindex.1 gold "" 10.1.2.4 different system
pmRoleTable OBJECT-TYPE
SYNTAX SEQUENCE OF PmRoleEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The role string table.
The agent must store role string associations in nonvolatile
storage."
::= { policyMgt 4 }
pmRoleEntry OBJECT-TYPE
SYNTAX PmRoleEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A role string entry associates a role string with an
individual element."
INDEX { pmRoleElement, pmRoleString, pmRoleContextName,
pmRoleTDomain, IMPLIED pmRoleTAddress }
::= { pmRoleTable 1 }
PmRoleEntry ::= SEQUENCE {
pmRoleElement RowPointer,
pmRoleString UTF8String,
pmRoleContextName SnmpAdminString,
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pmRoleTDomain TDomain,
pmRoleTAddress TAddress,
pmRoleStatus RowStatus
}
pmRoleElement OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The element to which this role string is associated.
If the agent assigns new indexes in the MIB table to
represent the same underlying element (re-indexing), the
agent will modify this value to contain the new index for the
underlying element."
::= { pmRoleEntry 1 }
pmRoleString OBJECT-TYPE
SYNTAX UTF8String (SIZE (0..64))
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The role string that is associated with an element through
this table.
A role string is an administratively specified characteristic
of a managed element (for example, an interface). It is a
selector for policy rules, to determine the applicability of
the rule to a particular managed element."
::= { pmRoleEntry 2 }
pmRoleContextName OBJECT-TYPE
SYNTAX SnmpAdminString
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"If the associated element is not in the default context for
the target system, this object is used to identify the
context. If the element is in the default context, this object
is equal to the empty string."
::= { pmRoleEntry 3 }
pmRoleTDomain OBJECT-TYPE
SYNTAX TDomain
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MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This object indicates the transport type of the address
contained in the pmRoleTAddress object. If there is no
address, this object will have the value '0.0'"
::= { pmRoleEntry 4 }
pmRoleTAddress OBJECT-TYPE
SYNTAX TAddress
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"If the associated element is on a remote system, this object
is used to identify the remote system. This object contains a
transport address. The format of this address depends on the
value of the snmpTargetAddrTDomain object. If the element is
on the local system this object will be the empty string."
::= { pmRoleEntry 5 }
pmRoleStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this role string."
::= { pmRoleEntry 6 }
-- Capabilities table
-- The pmCapabilitiesTable contains a description of
-- the inherent capabilities of the system so that scripts can
-- differentially apply code based on the capabilities and so that
-- management stations can learn of an agent's capabilities and
-- differentially install policies based on the capabilities.
pmCapabilitiesTable OBJECT-TYPE
SYNTAX SEQUENCE OF PmCapabilitiesEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The pmCapabilitiesTable contains a description of
the inherent capabilities of the system.
Note that it is not necessary to list all
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OIDs that a mechanism specific MIB Module supports, just the
base OID if the implementation is a fully compliant one. If
the implementation is not, then additional rows will exist in
the table that list the limitations or enhancements."
::= { policyMgt 6 }
pmCapabilitiesEntry OBJECT-TYPE
SYNTAX PmCapabilitiesEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The description of a capability or limitation of a
capability of the system. An entry will exist for each
domain and mechanism specific ability the system has. In
the case of a domain specific capability with no mechanism
specific parameters, the pmCapabilitiesSubType and all other
columns may be null. Entries will exist that contain
values for the pmCapabilitiesRestrictOID,
pmCapabilitiesRestrictType, pmCapabilitiesRestrictValue
and pmCapabilitiesRestrictString objects only when
an implementation is reporting a mechanism specific
restriction. Multiple entries are possible when more
than one restriction for a type or subtype are needed."
INDEX { pmCapabilitiesIndex }
::= { pmCapabilitiesTable 1 }
PmCapabilitiesEntry ::= SEQUENCE {
pmCapabilitiesIndex Unsigned32,
pmCapabilitiesType OBJECT IDENTIFIER,
pmCapabilitiesSubType OBJECT IDENTIFIER,
pmCapabilitiesModificationOID OBJECT IDENTIFIER,
pmCapabilitiesModificationType INTEGER,
pmCapabilitiesModificationValue Integer32,
pmCapabilitiesModificationString OCTET STRING
}
pmCapabilitiesIndex OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A unique index for this entry."
::= { pmCapabilitiesEntry 1 }
pmCapabilitiesType OBJECT-TYPE
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SYNTAX OBJECT IDENTIFIER
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The type of the capability represented by this entry.
The IANA will publish the list of identifiers that are valid
values for this object."
::= { pmCapabilitiesEntry 2 }
pmCapabilitiesSubType OBJECT-TYPE
SYNTAX OBJECT IDENTIFIER
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The sub type of capability is a pointer to a mechanism specific
set of capabilities supporting a base technology. In the case of
DIFFSERV, the OID value here would be the base OID of the
Differentiated Services Policy MIB Module."
::= { pmCapabilitiesEntry 3 }
pmCapabilitiesModificationOID OBJECT-TYPE
SYNTAX OBJECT IDENTIFIER
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The OID of the object that is either not supported, supported
with one or more limitations, or expanded by an implementation
specific module. If this columnar object is other than null then
there must be at least an entry in pmCapabilitiesModificationType.
Note that this need not be a leaf node or scalar object. If
an entire table is not supported, this value can be the base OID
for the table."
::= { pmCapabilitiesEntry 4 }
pmCapabilitiesModificationType OBJECT-TYPE
SYNTAX INTEGER {
unsupported(0),
restricted(1),
additional(2),
addvalue(3),
maxlimit(4),
minlimit(5)
}
MAX-ACCESS read-only
STATUS current
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DESCRIPTION
"An unsupported value indicates that the OID in
pmCapabilitiesModificationOID is not supported on
this system. A value of 1 indicates that the OID
is supported but with restricted values
These constraints are described in the
pmCapabilitiesModificationValue and
pmCapabilitiesModificationString objects. A value of
2 indicates a vendor specific extension to a standard.
The OID of the new object is pmCapabilitiesModificationOID.
For some implementations, additional functions may be
provided. addvalue indicates that this row of the table
describes an additional value that the object can take.
The specific value is in the pmCapabilitiesModificationValue.
The values of 4 and 5 indicate restrictions or the removal
of restrictions for the object identified."
::= { pmCapabilitiesEntry 5 }
pmCapabilitiesModificationValue OBJECT-TYPE
SYNTAX Integer32 (0..2147483647)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"If the value of pmCapabilitiesModificationType is 0, this
object will be null since 0 indicates no support for the
object at all. A value of 1 in the
pmCapabilitiesModificationType will be further modified by a
single integer value in this object that corresponds to
enumerated integer values that are not supported by the
system for the object that is identified in this row. This
value can also represent the limit values in the
pmCapabilitiesModificationType object."
::= { pmCapabilitiesEntry 6 }
pmCapabilitiesModificationString OBJECT-TYPE
SYNTAX OCTET STRING
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Any additional details or description or parameters needed."
::= { pmCapabilitiesEntry 7 }
pmSchedLocalTime OBJECT-TYPE
SYNTAX DateAndTime (SIZE (11))
MAX-ACCESS read-only
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STATUS current
DESCRIPTION
"The local time used by the scheduler. Schedules which
refer to calendar time will use the local time indicated
by this object. An implementation MUST return all 11 bytes
of the DateAndTime textual-convention so that a manager
may retrieve the offset from GMT time."
::= { policyMgt 7 }
--
-- The schedule table which controls the scheduler.
--
pmSchedTable OBJECT-TYPE
SYNTAX SEQUENCE OF PmSchedEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table defines schedules for policies."
::= { policyMgt 8 }
pmSchedEntry OBJECT-TYPE
SYNTAX PmSchedEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry describing a particular scheduled action.
Unless noted otherwise, writable objects of this row
can be modified independent of the current value of
pmSchedRowStatus, pmSchedAdminStatus and pmSchedOperStatus.
In particular, it is legal to modify pmSchedInterval,
pmSchedWeekDay, pmSchedMonth, pmSchedDay, pmSchedHour, and
pmSchedMinute when pmSchedRowStatus is active and
pmSchedAdminStatus and pmSchedOperStatus are both enabled."
INDEX { pmSchedIndex }
::= { pmSchedTable 1 }
PmSchedEntry ::= SEQUENCE {
pmSchedIndex Unsigned32,
pmSchedGroupIndex Unsigned32,
pmSchedDescr SnmpAdminString,
pmSchedInterval Unsigned32,
pmSchedWeekDay BITS,
pmSchedMonth BITS,
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pmSchedDay BITS,
pmSchedHour BITS,
pmSchedMinute BITS,
pmSchedDuration Unsigned32,
pmSchedType INTEGER,
pmSchedAdminStatus INTEGER,
pmSchedOperStatus INTEGER,
pmSchedStorageType StorageType,
pmSchedRowStatus RowStatus
}
pmSchedIndex OBJECT-TYPE
SYNTAX Unsigned32 (1..65535)
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The locally-unique, administratively assigned index for this
scheduling entry."
::= { pmSchedEntry 1 }
pmSchedGroupIndex OBJECT-TYPE
SYNTAX Unsigned32 (1..65535)
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The locally-unique, administratively assigned index for the
group that this scheduling entry belongs to.
To assign multiple schedule entries to the same group, the
pmSchedGroupIndex of each entry in the group will be set to
the same value. This pmSchedGroupIndex value must be equal to
the pmSchedIndex of one of the entries in the group. If the
entry is deleted whose pmSchedIndex equals the
pmSchedGroupIndex for the group, the agent will assign a new
pmSchedGroupIndex to all remaining members of the group.
If an entry is not a member of a group, its pmSchedGroupIndex
must be assigned to the value of its pmSchedIndex.
Policies that are controlled by a group of schedule entries
are active when any schedule in the group is active."
::= { pmSchedEntry 2 }
pmSchedDescr OBJECT-TYPE
SYNTAX SnmpAdminString
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MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The human readable description of the purpose of this
scheduling entry."
DEFVAL { ''H }
::= { pmSchedEntry 3 }
pmSchedInterval OBJECT-TYPE
SYNTAX Unsigned32
UNITS "seconds"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The number of seconds between two activations of
a periodic scheduler. Implementations must guarantee
that activations will not occur before at least
pmSchedInterval seconds have passed.
The scheduler must ignore all periodic schedules that
have a pmSchedInterval value of 0. A periodic schedule
with a scheduling interval of 0 seconds will therefore
never invoke an action.
Implementations may be forced to delay invocations in the
face of local constraints. A scheduled management function
should therefore not rely on the accuracy provided by the
scheduler implementation."
DEFVAL { 0 }
::= { pmSchedEntry 4 }
pmSchedWeekDay OBJECT-TYPE
SYNTAX BITS {
sunday(0),
monday(1),
tuesday(2),
wednesday(3),
thursday(4),
friday(5),
saturday(6)
}
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The set of weekdays on which the schedule should
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be active. Setting multiple bits will include several
weekdays in the set of possible weekdays for this schedule.
Setting all bits will cause the scheduler to ignore the
weekday."
DEFVAL { {} }
::= { pmSchedEntry 5 }
pmSchedMonth OBJECT-TYPE
SYNTAX BITS {
january(0),
february(1),
march(2),
april(3),
may(4),
june(5),
july(6),
august(7),
september(8),
october(9),
november(10),
december(11)
}
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The set of months during which the schedule should
be active. Setting multiple bits will include several
months in the set of possible months for this schedule.
Setting all bits will cause the scheduler to ignore the
month."
DEFVAL { {} }
::= { pmSchedEntry 6 }
pmSchedDay OBJECT-TYPE
SYNTAX BITS {
d1(0), d2(1), d3(2), d4(3), d5(4),
d6(5), d7(6), d8(7), d9(8), d10(9),
d11(10), d12(11), d13(12), d14(13), d15(14),
d16(15), d17(16), d18(17), d19(18), d20(19),
d21(20), d22(21), d23(22), d24(23), d25(24),
d26(25), d27(26), d28(27), d29(28), d30(29),
d31(30),
r1(31), r2(32), r3(33), r4(34), r5(35),
r6(36), r7(37), r8(38), r9(39), r10(40),
r11(41), r12(42), r13(43), r14(44), r15(45),
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r16(46), r17(47), r18(48), r19(49), r20(50),
r21(51), r22(52), r23(53), r24(54), r25(55),
r26(56), r27(57), r28(58), r29(59), r30(60),
r31(61)
}
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The set of days in a month on which a schedule
should be active. There are two sets of bits one can
use to define the day within a month:
Enumerations starting with the letter 'd' indicate a
day in a month relative to the first day of a month.
The first day of the month can therefore be specified
by setting the bit d1(0) and d31(30) means the last
day of a month with 31 days.
Enumerations starting with the letter 'r' indicate a
day in a month in reverse order, relative to the last
day of a month. The last day in the month can therefore
be specified by setting the bit r1(31), and r31(61) means
the first day of a month with 31 days.
Setting multiple bits will include several days in the set
of possible days for this schedule. Setting all bits will
cause the scheduler to ignore the day within a month.
Setting all bits starting with the letter 'd' or the
letter 'r' will also cause the scheduler to ignore the
day within a month."
DEFVAL { {} }
::= { pmSchedEntry 7 }
pmSchedHour OBJECT-TYPE
SYNTAX BITS {
h0(0), h1(1), h2(2), h3(3), h4(4),
h5(5), h6(6), h7(7), h8(8), h9(9),
h10(10), h11(11), h12(12), h13(13), h14(14),
h15(15), h16(16), h17(17), h18(18), h19(19),
h20(20), h21(21), h22(22), h23(23)
}
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The set of hours within a day during which the schedule
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should be active."
DEFVAL { {} }
::= { pmSchedEntry 8 }
pmSchedMinute OBJECT-TYPE
SYNTAX BITS {
m0(0), m1(1), m2(2), m3(3), m4(4),
m5(5), m6(6), m7(7), m8(8), m9(9),
m10(10), m11(11), m12(12), m13(13), m14(14),
m15(15), m16(16), m17(17), m18(18), m19(19),
m20(20), m21(21), m22(22), m23(23), m24(24),
m25(25), m26(26), m27(27), m28(28), m29(29),
m30(30), m31(31), m32(32), m33(33), m34(34),
m35(35), m36(36), m37(37), m38(38), m39(39),
m40(40), m41(41), m42(42), m43(43), m44(44),
m45(45), m46(46), m47(47), m48(48), m49(49),
m50(50), m51(51), m52(52), m53(53), m54(54),
m55(55), m56(56), m57(57), m58(58), m59(59)
}
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The set of minutes within an hour when the schedule
should be active."
DEFVAL { {} }
::= { pmSchedEntry 9 }
pmSchedDuration OBJECT-TYPE
SYNTAX Unsigned32
UNITS "seconds"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The number of seconds the schedule will be active after
invocation."
::= { pmSchedEntry 10 }
pmSchedType OBJECT-TYPE
SYNTAX INTEGER {
periodic(1),
calendar(2),
oneshot(3)
}
MAX-ACCESS read-create
STATUS current
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DESCRIPTION
"The type of this schedule. The value periodic(1) indicates
that this entry specifies a periodic schedule. A periodic
schedule is defined by the value of pmSchedInterval. The
values of pmSchedWeekDay, pmSchedMonth, pmSchedDay,
pmSchedHour and pmSchedMinute are ignored.
The value calendar(2) indicates that this entry describes a
calendar schedule. A calendar schedule is defined by the
values of pmSchedWeekDay, pmSchedMonth, pmSchedDay,
pmSchedHour and pmSchedMinute. The value of pmSchedInterval
is ignored. A calendar schedule will be active on all local
times that satisfy the bits set in pmSchedWeekDay,
pmSchedMonth, pmSchedDay, pmSchedHour and pmSchedMinute.
The value oneshot(3) indicates that this entry describes a
one-shot schedule. A one-shot schedule is similar to a
calendar schedule with the additional feature that it
disables itself by changing in the `finished'
pmSchedOperStatus once the schedule becomes inactive after
its first activation.
Changing a schedule's type is equivalent to deleting the
old-type schedule and creating a new-type one."
DEFVAL { periodic }
::= { pmSchedEntry 11 }
pmSchedAdminStatus OBJECT-TYPE
SYNTAX INTEGER {
enabled(1),
disabled(2)
}
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The desired state of the schedule."
DEFVAL { disabled }
::= { pmSchedEntry 12 }
pmSchedOperStatus OBJECT-TYPE
SYNTAX INTEGER {
enabled(1),
disabled(2),
finished(3)
}
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MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current operational state of this schedule. The state
enabled(1) indicates this entry is active and that the
scheduler will invoke actions at appropriate times. The
disabled(2) state indicates that this entry is currently
inactive and ignored by the scheduler. The finished(3)
state indicates that the schedule has ended. Schedules
in the finished(3) state are ignored by the scheduler.
A one-shot schedule enters the finished(3) state when it
deactivates itself."
::= { pmSchedEntry 13 }
pmSchedStorageType OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This object defines whether this scheduled action is kept
in volatile storage and lost upon reboot or if this row is
backed up by non-volatile or permanent storage.
Conceptual rows having the value `permanent' must allow write
access to the columnar objects pmSchedDescr, pmSchedInterval,
pmSchedWeekDay, pmSchedMonth, pmSchedDay, pmSchedHour,
pmSchedMinute and pmSchedAdminStatus."
DEFVAL { volatile }
::= { pmSchedEntry 14 }
pmSchedRowStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this scheduled action."
::= { pmSchedEntry 15 }
-- Policy Tracking
pmTrackingPolicyToElementTable OBJECT-TYPE
SYNTAX SEQUENCE OF PmTrackingPolicyToElementEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
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"The pmTrackingPolicyToElementTable describes what elements
are under control of a policy. This table is indexed in
order to optimize retrieval of the entire status for a given
policy."
::= { policyMgt 9 }
pmTrackingPolicyToElementEntry OBJECT-TYPE
SYNTAX PmTrackingPolicyToElementEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the pmTrackingPolicyToElementTable. The
pmPolicyIndex in the index specifies the policy tracked by
this entry."
INDEX { pmPolicyIndex, pmTrackingPolicyToElementElement }
::= { pmTrackingPolicyToElementTable 1 }
PmTrackingPolicyToElementEntry ::= SEQUENCE {
pmTrackingPolicyToElementElement RowPointer,
pmTrackingPolicyToElementInfo BITS
}
pmTrackingPolicyToElementElement OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The element that is configured by the associated policy."
::= { pmTrackingPolicyToElementEntry 1 }
pmTrackingPolicyToElementInfo OBJECT-TYPE
SYNTAX BITS {
filterMatched(0),
actionSkippedDueToPrecedence(1),
filterRunTimeException(2),
filterUserSignal(3),
actionRunTimeException(4),
actionUserSignal(5)
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object returns information about the previous policy
script executions.
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If the filterMatched(0) bit is set, the last execution of the
associated policy filter returned TRUE.
If the actionSkippedDueToPrecedence(1) bit is set, the last
execution of the associated policy filter returned TRUE but
the action is not active because it was trumped by a matching
policy filter in the same policy group with a higher
precedence value.
If the filterRunTimeException(2) bit is set, the last
execution of the associated policy filter encountered a
run-time exception and aborted.
If the filterUserSignal(3) bit is set, the last
execution of the associated policy filter called the
signalException() function.
If the actionRunTimeException(4) bit is set, the last
execution of the associated policy action encountered a
run-time exception and aborted.
If the actionUserSignal(5) bit is set, the last
execution of the associated policy action called the
signalException() function.
Entries will only exist in this table of one or more bits are
set. In particular, if an entry does not exist for a
particular policy/element combination, it can be assumed that
the policy's filter did not match this element."
::= { pmTrackingPolicyToElementEntry 2 }
-- Element to Policy Table
pmTrackingElementToPolicyTable OBJECT-TYPE
SYNTAX SEQUENCE OF PmTrackingElementToPolicyEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The pmTrackingElementToPolicyTable describes what policies
are controlling an element. This table is indexed in
order to optimize retrieval of the status of all policies
active for a given element."
::= { policyMgt 10 }
pmTrackingElementToPolicyEntry OBJECT-TYPE
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SYNTAX PmTrackingElementToPolicyEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the pmTrackingElementToPolicyTable. The
pmPolicyIndex in the index specifies the policy tracked by
this entry."
INDEX { pmTrackingElementToPolicyElement, pmPolicyIndex }
::= { pmTrackingElementToPolicyTable 1 }
PmTrackingElementToPolicyEntry ::= SEQUENCE {
pmTrackingElementToPolicyElement RowPointer,
pmTrackingElementToPolicyStatus INTEGER
}
pmTrackingElementToPolicyElement OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The element configured by the associated policy."
::= { pmTrackingElementToPolicyEntry 1 }
pmTrackingElementToPolicyStatus OBJECT-TYPE
SYNTAX INTEGER {
off(0),
on(1),
forceOff(2)
}
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"The status of this policy-element relationship. This value
will be on(1) if the calendar for the policy is active and if
the associated policyFilter returned 1 for this element.
Entries will not exist in this table if their status would be
off(0).
A policy can be forcibly disabled on a particular element
by setting this value to forceOff(2). The agent should then
act as if the policyFilter failed for this element. The
forceOff(2) state will persist (even across reboots) until
this value is set to on(1) by a management request. Even if
the policyFilter later fails for this element, this value
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will stay in the forceOff(2) state."
::= { pmTrackingElementToPolicyEntry 2 }
-- Policy Debugging Table
-- Policies that have debugging turned on will generate a log entry in
-- the policy debugging table for every runtine exception that occurs
-- in either the filter or action code.
pmDebuggingTable OBJECT-TYPE
SYNTAX SEQUENCE OF PmDebuggingEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The pmDebuggingTable logs debugging messages when
policies experience run-time exceptions in either the filter
or action code and the associated pmPolicyDebugging object
has been turned on."
::= { policyMgt 11 }
pmDebuggingEntry OBJECT-TYPE
SYNTAX PmDebuggingEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the pmDebuggingTable. The pmPolicyIndex in the
index specifies the policy that encountered the exception
that led to this log entry."
INDEX { pmPolicyIndex, pmDebuggingElement,
pmDebuggingLogIndex }
::= { pmDebuggingTable 1 }
PmDebuggingEntry ::= SEQUENCE {
pmDebuggingElement RowPointer,
pmDebuggingLogIndex Unsigned32,
pmDebuggingMessage UTF8String
}
pmDebuggingElement OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The element the policy was executing on when it encountered
the error that led to this log entry."
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::= { pmDebuggingEntry 1 }
pmDebuggingLogIndex OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"A unique index for this log entry amongst other log entries
for this policy/element combination."
::= { pmDebuggingEntry 2 }
pmDebuggingMessage OBJECT-TYPE
SYNTAX UTF8String (SIZE (0..128))
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"An error message generated by the policy execution environment."
::= { pmDebuggingEntry 3 }
-- Notification Registration Table
-- A management station may choose not to install policies to a
-- system that depend on roles or capabilities that don't exist on any
-- elements in the system. However, the management station must be able
-- to quickly learn if new roles or capabilities are added to the
-- system so that it can immediately install the policies that make
-- use of that new role or capability. This table allows a management
-- station to register itself so that it will receive
-- pmNewRoleNotifications and pmNewCapabilityNotifications whenever a
-- role or capability first appears on the system.
--
-- pmNewRoleNotifications and pmNewCapabilityNotifications are sent in
-- Inform PDU's so they are automatically retransmitted if they are
-- not acknowledged.
--
-- The procedure to guarantee accurate knowledge of roles and
-- capabilities is as follows:
--
-- Step 1: The NMS registers itself in the pmNotificationRegTable
-- Whenever it receives a notification, it adds the new role
-- or capability to its internal database for that system.
-- Followed immediately by:
-- Step 2: The NMS retrieves the roles and capabilities from the
-- system from the pmRoleTable and the
-- pmCapabilitiesTable, adding this information to its
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-- internal database.
-- Followed immediately by:
-- Step 3: The NMS installs policies on the system, potentially
-- skipping policies that depend on roles or capabilities
-- that haven't been inserted into the internal database.
-- Followed immediately by:
-- Step 4: Whenever a notification indicates a new role or
-- capability that requires new policies to be installed,
-- it will immediately install such policies. The NMS will
-- continue this step indefinitely.
--
-- Note that using this algorithm to avoid installing "unnecessary"
-- policies may result in delays in having the policy available when
-- the policy becomes necessary. This delay could become extensive if
-- an interruption of communications prevents the notification from
-- being delivered and/or the policy from being installed, causing
-- the sytem to not be in compliance with policy for a period of
-- time. In particular, if the policy is enforcing security rules,
-- this could open up security vulnerabilities during this period of
-- time.
pmNotificationRegTable OBJECT-TYPE
SYNTAX SEQUENCE OF PmNotificationRegEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A manager that wishes to receive notifications about new
roles or capabilities on an agent places an entry in the
notification registration table. pmNewRoleNotifications and
pmNewCapabilityNotifications will then be sent to the target
specified in the associated snmpTargetAddr entry. These
notifications will be sent until the entry is removed from
this table."
::= { policyMgt 12 }
pmNotificationRegEntry OBJECT-TYPE
SYNTAX PmNotificationRegEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the pmNotificationRegTable."
INDEX { pmNotificationRegIndex }
::= { pmNotificationRegTable 1 }
PmNotificationRegEntry ::= SEQUENCE {
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pmNotificationRegIndex Unsigned32,
pmNotificationRegSnmpTargetAddrName SnmpAdminString,
pmNotificationRegStorageType StorageType,
pmNotificationRegStatus RowStatus
}
pmNotificationRegIndex OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A unique index for this entry."
::= { pmNotificationRegEntry 1 }
pmNotificationRegSnmpTargetAddrName OBJECT-TYPE
SYNTAX SnmpAdminString
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The snmpTargetAddrName of an associated
snmpTargetAddrEntry. When the following conditions are true,
pmNewRoleNotifications and pmNewCapabilityNotifications
should be sent to the specified target:
1) The pmNotificationRegEntry is active
2) The associated snmpTargetAddr entry is fully
configured and active.
3) The associated snmpTargetParams entry is fully
configured and active."
::= { pmNotificationRegEntry 2 }
pmNotificationRegStorageType OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This object defines whether this row is kept
in volatile storage and lost upon reboot or if this row is
backed up by non-volatile or permanent storage."
::= { pmNotificationRegEntry 3 }
pmNotificationRegStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
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DESCRIPTION
"The status of this entry."
::= { pmNotificationRegEntry 4 }
-- Notifications
pmNotifications OBJECT IDENTIFIER ::= { policyMgt 13 }
pmNewRoleNotification NOTIFICATION-TYPE
OBJECTS { pmRoleString }
STATUS current
DESCRIPTION
"The pmNewRoleNotification is sent when an agent is configured with
its first instance of a previously unused role string (not
every time a new element is given a particular role).
An instance of the pmRoleString object is sent containing
the new roleString. In the event that two or more elements are
given the same role simultaneously, it is an
implementation-dependent matter as to which pmRoleString
instance will be included in the notification."
::= { pmNotifications 1 }
pmNewCapabilityNotification NOTIFICATION-TYPE
OBJECTS { pmCapabilitiesType }
STATUS current
DESCRIPTION
"The pmNewCapabilityNotification is sent when an agent
gains a new capability that did not previously exist in any
element on the system (not every time an element gains a
particular role).
An instance of the pmCapabilitiesType object is sent containing
the identity of the new capability. In the event that two or
more elements gain the same role simultaneously, it is an
implementation-dependent matter as to which pmCapabilitiesType
instance will be included in the notification."
::= { pmNotifications 2 }
-- Compliance Statements
pmConformance OBJECT IDENTIFIER ::= { policyMgt 20 }
pmCompliances OBJECT IDENTIFIER ::= { pmConformance 1 }
pmGroups OBJECT IDENTIFIER ::= { pmConformance 2 }
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pmCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"Describes the requirements for conformance to
the Policy-Based Management MIB"
MODULE -- this module
MANDATORY-GROUPS { pmPolicyManagementGroup, pmSchedGroup,
pmNotificationGroup }
::= { pmCompliances 1 }
pmPolicyManagementGroup OBJECT-GROUP
OBJECTS { pmPolicyGroup, pmPolicyPrecedence,
pmPolicySchedule, pmPolicyFilter, pmPolicyAction,
pmPolicyParameters,
pmPolicyFilterMaxLatency, pmPolicyActionMaxLatency,
pmPolicyMaxIterations,
pmPolicyDescription, pmPolicyMatches,
pmPolicyAbnormalTerminations,
pmPolicyExecutionErrors, pmPolicyDebugging,
pmPolicyStorageType, pmPolicyAdminStatus,
pmPolicyRowStatus, pmPolicyCodeText, pmPolicyCodeStatus,
pmElementTypeRegOIDPrefix, pmElementTypeRegMaxLatency,
pmElementTypeRegName, pmElementTypeRegStorageType,
pmElementTypeRegRowStatus,
pmRoleString, pmRoleContextName, pmRoleTDomain,
pmRoleTAddress, pmRoleStatus,
pmCapabilitiesType, pmCapabilitiesSubType,
pmCapabilitiesModificationOID,
pmCapabilitiesModificationType,
pmCapabilitiesModificationValue,
pmCapabilitiesModificationString,
pmTrackingPolicyToElementInfo,
pmTrackingElementToPolicyStatus,
pmDebuggingElement, pmDebuggingLogIndex,
pmDebuggingMessage,
pmNotificationRegSnmpTargetAddrName,
pmNotificationRegStorageType, pmNotificationRegStatus }
STATUS current
DESCRIPTION
"Objects that allow for the creation and management of
configuration policies."
::= { pmGroups 1 }
pmSchedGroup OBJECT-GROUP
OBJECTS { pmSchedLocalTime, pmSchedGroupIndex,
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pmSchedDescr, pmSchedInterval, pmSchedWeekDay,
pmSchedMonth, pmSchedDay, pmSchedHour, pmSchedMinute,
pmSchedDuration, pmSchedType, pmSchedAdminStatus,
pmSchedOperStatus, pmSchedStorageType, pmSchedRowStatus
}
STATUS current
DESCRIPTION
"Objects that allow for the scheduling of policies."
::= { pmGroups 2 }
pmNotificationGroup NOTIFICATION-GROUP
NOTIFICATIONS { pmNewRoleNotification,
pmNewCapabilityNotification }
STATUS current
DESCRIPTION
"Notifications sent by an Policy MIB agent."
::= { pmGroups 3 }
pmBaseFunctionLibrary OBJECT IDENTIFIER ::= { pmGroups 4 }
END
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12. Security Considerations
There are a number of management objects defined in this MIB
that have a MAX-ACCESS clause of read-write and/or read-
create. Such objects may be considered sensitive or
vulnerable in some network environments. The support for SET
operations in a non-secure environment without proper
protection can have a negative effect on network operations.
SNMPv1 by itself is not a secure environment. Even if the
network itself is secure (for example by using IPSec), even
then, there is no control as to who on the secure network is
allowed to access and GET/SET (read/change/create/delete) the
objects in this MIB.
It is recommended that the implementors consider the security
features as provided by the SNMPv3 framework. Specifically,
the use of the User-based Security Model RFC 2574 [12] and the
View-based Access Control Model RFC 2575 [15] is recommended.
It is then a customer/user responsibility to ensure that the
SNMP entity giving access to an instance of this MIB, is
properly configured to give access to the objects only to
those principals (users) that have legitimate rights to indeed
GET or SET (change/create/delete) them.
Access control for SNMP requests made to the local system
depends on the security credentials of the last entity to
modify any object in the filter or action for a policy. These
security credentials are the input parameters for
isAccessAllowed from the Architecture for Describing SNMP
Management Frameworks[1].
Some policies may be designed to ensure the security of a
network. If these policies have not been installed pending the
appearance of a role or capability, some delay will occur in
the activation of these policies when the role or capability
appears because a responsible manager must notice the change
and install the policy. This delay may expose the device or
the network to unacceptable security vulnerabilities during
this delay. If the role or capability appears during a time of
network stress or when the management station is unavailable,
this delay could be extensive, further increasing the risk. It
is recommended that management stations install any security-
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related policy that might ever be needed on a particular
managed device, even if a nonexistent role or capability
suggests it isn't needed at a given time.
13. Acknowledgements
The authors gratefully acknowledge the significant
contributions to this work made by Jeff Case, Joel Halpern,
Pablo Halpern, and David Partain.
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14. References
[1] Harrington, D., Presuhn, R., and B. Wijnen, "An
Architecture for Describing SNMP Management Frameworks",
RFC 2571, April 1999.
[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 2572, April
1999.
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[12] Blumenthal, U., and B. Wijnen, "User-based Security Model
(USM) for version 3 of the Simple Network Management
Protocol (SNMPv3)", RFC 2574, April 1999.
[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 2573, April 1999.
[15] Wijnen, B., Presuhn, R., and K. McCloghrie, "View-based
Access Control Model (VACM) for the Simple Network
Management Protocol (SNMP)", RFC 2575, April 1999.
[16] McCloghrie, K. and M. Rose, Editors, "Management
Information Base for Network Management of TCP/IP-based
internets: MIB-II", STD 17, RFC 1213, Hughes LAN Systems,
Performance Systems International, March 1991.
[17] McCloghrie, K. and F. Kastenholz, "The Interfaces Group
MIB using SMIv2", RFC 2233, Cisco Systems, FTP Software,
November 1997.
[18] Case, J., Mundy, R., Partain, D., and B. Stewart,
"Introduction to Version 3 of the Internet-standard
Network Management Framework", RFC 2570, April 1999.
[19] International Standards Organization, "Information
Technology - Programming Languages - C++", ISO/IEC
14882-1998
[20] Levi, D. and J. Schoenwaelder, "Definitions of Managed
Objects for Scheduling Management Operations", RFC 2591,
May 1999.
[21] ECMA, "ECMAScript Language Specification", ECMA-262,
December 1999
15. 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
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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.
16. Full Copyright Statement
Copyright (C) The Internet Society (2001). 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
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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.
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Table of Contents
1 Abstract .............................................. 1
2 The SNMP Management Framework ......................... 2
3 Overview .............................................. 4
4 Policy-Based Management Architecture .................. 5
5 Policy Based Management Execution Environment ......... 8
5.1 Terminology ......................................... 8
5.2 Element Discovery ................................... 9
5.2.1 Implementation Notes .............................. 10
5.3 Element Filtering ................................... 11
5.3.1 Implementation Notes .............................. 11
5.4 Policy Enforcement .................................. 11
5.4.1 Implementation Notes .............................. 12
6 The PolicyScript Language ............................. 13
6.1 Formal Definition ................................... 14
6.2 Variables ........................................... 17
6.2.1 The var class ..................................... 18
6.3 PolicyScript QuickStart Guide ....................... 22
6.3.1 Quickstart for C Programmers ...................... 24
6.3.2 Quickstart for Perl Programmers ................... 24
6.3.3 Quickstart for TCL Programmers .................... 24
6.3.4 Quickstart for Python Programmers ................. 25
6.3.5 Quickstart for JavaScript/ECMAScript/JScript
Programmers ........................................ 25
7 Address of `this element' ............................. 25
8 Accessor Functions .................................... 26
9 Base Accessor Function Library ........................ 26
9.1 SNMP Accessor Functions ............................. 27
9.1.1 Form of SNMP Values ............................... 28
9.1.2 Convenience SNMP Functions ........................ 29
9.1.2.1 getvar() ........................................ 29
9.1.2.2 exists() ........................................ 29
9.1.2.3 setvar() ........................................ 30
9.1.2.4 searchcolumn() .................................. 31
9.1.2.5 setRowStatus() .................................. 33
9.1.2.6 counterRate() ................................... 34
9.1.2.7 counter32Delta() ................................ 35
9.1.3 General SNMP Functions ............................ 35
9.1.3.1 newPDU() ........................................ 37
9.1.3.2 writeVar() ...................................... 37
9.1.3.3 readVar() ....................................... 38
9.1.3.4 snmpsend() ...................................... 38
9.2 Constants ........................................... 39
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9.3 Policy Configuration Accessor Functions ............. 41
9.3.1 roleMatch() ....................................... 41
9.3.2 capMatch() ........................................ 41
9.3.3 elementName() ..................................... 42
9.3.4 ic() .............................................. 42
9.3.5 iv() .............................................. 42
9.3.6 setScratchpad() ................................... 43
9.3.7 getScratchpad() ................................... 44
9.3.8 Constants ......................................... 45
9.3.9 signalException() ................................. 46
9.3.10 getParameters() .................................. 46
9.4 Utility Accessor Functions .......................... 46
9.4.1 regexp() .......................................... 47
9.4.2 regexp_replace() .................................. 47
9.4.3 oidlen() .......................................... 47
9.4.4 oidncmp() ......................................... 48
9.4.5 insubtree() ....................................... 48
9.4.6 subid() ........................................... 48
9.4.7 subidwrite() ...................................... 48
9.4.8 oidsplice() ....................................... 49
9.4.9 parseindex() ...................................... 49
9.4.10 stringToDotted() ................................. 51
9.4.11 Integer() ........................................ 51
9.4.12 String() ......................................... 51
9.4.13 Type() ........................................... 51
9.4.14 chr() ............................................ 52
9.4.15 ord() ............................................ 52
9.4.16 substr() ......................................... 52
9.5 Library Accessor Functions .......................... 53
10 Schedule Table ....................................... 53
10.1 Periodic Schedules ................................. 54
10.2 Calendar Schedules ................................. 54
10.3 One-shot Schedules ................................. 55
11 Definitions .......................................... 56
12 Security Considerations .............................. 96
13 Acknowledgements ..................................... 97
14 References ........................................... 98
15 Intellectual Property ................................ 99
16 Full Copyright Statement ............................. 100
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