RFC3231

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Network Working Group D. Levi Request for Comments: 3231 Nortel Networks Obsoletes: 2591 J. Schoenwaelder Category: Standards Track TU Braunschweig

                                                        January 2002
               Definitions of Managed Objects for
                Scheduling Management Operations

Status of this Memo

This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.

Copyright Notice

Copyright (C) The Internet Society (2002). All Rights Reserved.

Abstract

This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes a set of managed objects that are used to schedule management operations periodically or at specified dates and times.

This document obsoletes RFC 2591.

Introduction

This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes a set of managed objects that are used to schedule management operations periodically or at specified dates and times.

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 RFC2119.

The SNMP Management Framework

The SNMP Management Framework presently consists of five major components:

o An overall architecture, described in RFC 2571 RFC2571.

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 RFC1155, STD 16, RFC 1212 RFC1212 and RFC 1215
  RFC1215.  The second version, called SMIv2, is described in STD
  58, RFC 2578 RFC2578, STD 58, RFC 2579 RFC2579 and STD 58, RFC
  2580 RFC2580.

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 RFC1157.  A second version of the
  SNMP message protocol, which is not an Internet standards track
  protocol, is called SNMPv2c and described in RFC 1901 RFC1901
  and RFC 1906 RFC1906.  The third version of the message protocol
  is called SNMPv3 and described in RFC 1906 RFC1906, RFC 2572
  RFC2572 and RFC 2574 RFC2574.

o Protocol operations for accessing management information. The

  first set of protocol operations and associated PDU formats is
  described in STD 15, RFC 1157 RFC1157.  A second set of protocol
  operations and associated PDU formats is described in RFC 1905
  RFC1905.

o A set of fundamental applications described in RFC 2573 RFC2573

  and the view-based access control mechanism described in RFC 2575
  RFC2575.

A more detailed introduction to the current SNMP Management Framework can be found in RFC 2570 RFC2570.

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

This memo specifies a MIB module that is compliant to the SMIv2. A MIB conforming to the SMIv1 can be produced through the appropriate translations. The resulting translated MIB must be semantically equivalent, except where objects or events are omitted because no translation is possible (use of Counter64). Some machine readable information in SMIv2 will be converted into textual descriptions in SMIv1 during the translation process. However, this loss of machine readable information is not considered to change the semantics of the MIB.

Overview

The MIB defined in this memo provides the scheduling of actions periodically or at specified dates and times. The actions can be used to realize on-duty / off-duty schedules or to trigger management functions in a distributed management application.

Schedules can be enabled or disabled by modifying a control object. This allows for pre-configured schedules which are activated or deactivated by some other management functions.

The term `scheduler' is used throughout this memo to refer to the entity which implements the scheduling MIB and which invokes the actions at the specified points in time.

Periodic Schedules

Periodic schedules are based on fixed time periods between the initiation of scheduled actions. Periodic schedules are defined by specifying the number of seconds between two initiations. The time needed to complete the action is usually not known by the scheduler and does therefore not influence the next scheduling point.

Implementations must guarantee that action invocations will not occur before their next scheduled time. However, implementations may be forced to delay invocations in the face of local constraints (e.g., a heavy load on higher-priority tasks). An accumulation of such delays would result in a drift of the scheduling interval with respect to time, and should be avoided.

Scheduled actions collecting statistical data should retrieve time stamps from the data source and not rely on the accuracy of the periodic scheduler in order to obtain accurate statistics.

Calendar Schedules

Calendar schedules trigger scheduled actions 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 triggers an action every 15 minutes on a given weekday.

Months, days and weekdays are specified using the objects schedMonth, schedDay and schedWeekDay 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 schedWeekDay restricts the schedule to Mondays and Fridays.

The bit fields for schedMonth, schedDay and schedWeekDay are combined using an AND operation. For example, setting the bits june(5) and july(6) in schedMonth and combining it with the bits monday(1) and friday(5) set in schedWeekDay 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 an action. For example, one can define a calendar schedule which should trigger an action on February 31st. Schedules like this will simply be ignored by the scheduler.

Finally, calendar schedules are always expressed in local time. A scalar, schedLocalTime, is provided so that a manager can retrieve the notion of local time and the offset to GMT time.

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 once an action has been invoked.

Time Transitions

A time transition occurs when the Schedule MIB's notion of time (as reported by schedLocalTime) is changed so that time continuity is lost. Time transitions may be caused by daylight savings times or administrative changes of the system's notion of time.

There are two possible situations when a time transition occurs.

First, time may be set backwards, in which case particular times will appear to occur twice. These are called 'ambiguous times'. Second, time may be set forwards, in which case particular times will not occur. These are called 'nonexistent times'.

When an action is configured in the Schedule MIB to occur at an ambiguous time, the action will be invoked at all occurrences of the ambiguous time. For example, if an action is scheduled to occur at 2:10 am, and a time transition occurs at 3:00 am which sets the clock back to 2:00 am, the action will be invoked twice.

When an action is configured in the Schedule MIB to occur at a nonexistent time, the action will not be invoked at all. For example, if an action is scheduled to occur at 2:10 am, and a time transition occurs at 2:00 am which sets the clock to 3:00 am, the action will not be invoked.

Actions

Scheduled actions are modeled by SNMP set operations on local MIB variables. Scheduled actions described in this MIB are further restricted to objects of type INTEGER. This restriction does not limit the usefulness of the MIB. Simple schedules such as on-duty / off-duty schedules for resources that have a status MIB object (e.g. ifAdminStatus) are possible.

More complex actions can be realized by triggering a management script which is responsible for performing complex state transitions. A management script can also be used to perform SNMP set operations on remote SNMP engines.

Definitions

DISMAN-SCHEDULE-MIB DEFINITIONS ::= BEGIN

IMPORTS

   MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE,
   Integer32, Unsigned32, Counter32, mib-2, zeroDotZero
       FROM SNMPv2-SMI
   TEXTUAL-CONVENTION,
   DateAndTime, RowStatus, StorageType, VariablePointer
       FROM SNMPv2-TC
   MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
       FROM SNMPv2-CONF
   SnmpAdminString
       FROM SNMP-FRAMEWORK-MIB;

schedMIB MODULE-IDENTITY

   LAST-UPDATED "200201070000Z"
   ORGANIZATION "IETF Distributed Management Working Group"
   CONTACT-INFO
       "WG EMail:  [email protected]
        Subscribe: [email protected]
        Chair:     Randy Presuhn
                   BMC Software, Inc.
        Postal:    Office 1-3141
                   2141 North First Street
                   San Jose,  California 95131
                   USA
        EMail:     [email protected]
        Phone:     +1 408 546-1006
        Editor:    David B. Levi
                   Nortel Networks
        Postal:    4401 Great America Parkway
                   Santa Clara, CA 95052-8185
                   USA
        EMail:     [email protected]
        Phone:     +1 865 686 0432
        Editor:    Juergen Schoenwaelder
                   TU Braunschweig
        Postal:    Bueltenweg 74/75
                   38106 Braunschweig
                   Germany
        EMail:     [email protected]
        Phone:     +49 531 391-3283"
   DESCRIPTION
       "This MIB module defines a MIB which provides mechanisms to
        schedule SNMP set operations periodically or at specific
        points in time."
   REVISION    "200201070000Z"
   DESCRIPTION
       "Revised version, published as RFC 3231.
        This revision introduces a new object type called
        schedTriggers.  Created new conformance and compliance
        statements that take care of the new schedTriggers object.
        Several clarifications have been added to remove ambiguities
        that were discovered and reported by implementors."
   REVISION    "199811171800Z"
   DESCRIPTION
       "Initial version, published as RFC 2591."
   ::= { mib-2 63 }

-- -- The various groups defined within this MIB definition: --

schedObjects OBJECT IDENTIFIER ::= { schedMIB 1 } schedNotifications OBJECT IDENTIFIER ::= { schedMIB 2 } schedConformance OBJECT IDENTIFIER ::= { schedMIB 3 }

-- -- Textual Conventions: --

SnmpPduErrorStatus ::= TEXTUAL-CONVENTION

   STATUS       current
   DESCRIPTION
       "This TC enumerates the SNMPv1 and SNMPv2 PDU error status
        codes as defined in RFC 1157 and RFC 1905.  It also adds a
        pseudo error status code `noResponse' which indicates a
        timeout condition."
   SYNTAX      INTEGER {
                   noResponse(-1),
                   noError(0),
                   tooBig(1),
                   noSuchName(2),
                   badValue(3),
                   readOnly(4),
                   genErr(5),
                   noAccess(6),
                   wrongType(7),
                   wrongLength(8),
                   wrongEncoding(9),
                   wrongValue(10),
                   noCreation(11),
                   inconsistentValue(12),
                   resourceUnavailable(13),
                   commitFailed(14),
                   undoFailed(15),
                   authorizationError(16),
                   notWritable(17),
                   inconsistentName(18)
               }

-- -- Some scalars which provide information about the local time zone. --

schedLocalTime OBJECT-TYPE

   SYNTAX      DateAndTime (SIZE (11))
   MAX-ACCESS  read-only
   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."
   ::= { schedObjects 1 }

-- -- The schedule table which controls the scheduler. --

schedTable OBJECT-TYPE

   SYNTAX      SEQUENCE OF SchedEntry
   MAX-ACCESS  not-accessible
   STATUS      current
   DESCRIPTION
       "This table defines scheduled actions triggered by
        SNMP set operations."
   ::= { schedObjects 2 }

schedEntry OBJECT-TYPE

   SYNTAX      SchedEntry
   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
        schedRowStatus, schedAdminStatus and schedOperStatus.
        In particular, it is legal to modify schedInterval
        and the objects in the schedCalendarGroup when
        schedRowStatus is active and schedAdminStatus and
        schedOperStatus are both enabled."
   INDEX { schedOwner, schedName }
   ::= { schedTable 1 }

SchedEntry ::= SEQUENCE {

   schedOwner          SnmpAdminString,
   schedName           SnmpAdminString,
   schedDescr          SnmpAdminString,
   schedInterval       Unsigned32,
   schedWeekDay        BITS,
   schedMonth          BITS,
   schedDay            BITS,
   schedHour           BITS,
   schedMinute         BITS,
   schedContextName    SnmpAdminString,
   schedVariable       VariablePointer,
   schedValue          Integer32,
   schedType           INTEGER,
   schedAdminStatus    INTEGER,
   schedOperStatus     INTEGER,
   schedFailures       Counter32,
   schedLastFailure    SnmpPduErrorStatus,
   schedLastFailed     DateAndTime,
   schedStorageType    StorageType,
   schedRowStatus      RowStatus,
   schedTriggers       Counter32

}

schedOwner OBJECT-TYPE

   SYNTAX      SnmpAdminString (SIZE(0..32))
   MAX-ACCESS  not-accessible
   STATUS      current
   DESCRIPTION
       "The owner of this scheduling entry.  The exact semantics of
        this string are subject to the security policy defined by
        the security administrator."
   ::= { schedEntry 1 }

schedName OBJECT-TYPE

   SYNTAX      SnmpAdminString (SIZE(1..32))
   MAX-ACCESS  not-accessible
   STATUS      current
   DESCRIPTION
       "The locally-unique, administratively assigned name for this
        scheduling entry.  This object allows a schedOwner to have
        multiple entries in the schedTable."
   ::= { schedEntry 2 }

schedDescr OBJECT-TYPE

   SYNTAX      SnmpAdminString
   MAX-ACCESS  read-create
   STATUS      current
   DESCRIPTION
       "The human readable description of the purpose of this
        scheduling entry."
   DEFVAL      { "" }
   ::= { schedEntry 3 }

schedInterval OBJECT-TYPE

   SYNTAX      Unsigned32
   UNITS       "seconds"
   MAX-ACCESS  read-create
   STATUS      current
   DESCRIPTION
       "The number of seconds between two action invocations of
        a periodic scheduler.  Implementations must guarantee
        that action invocations will not occur before at least
        schedInterval seconds have passed.
        The scheduler must ignore all periodic schedules that
        have a schedInterval 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.
        Note that implementations which maintain a list of pending
        activations must re-calculate them when this object is
        changed."
   DEFVAL      { 0 }
   ::= { schedEntry 4 }

schedWeekDay 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 scheduled action should
        take place.  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.
        Note that implementations which maintain a list of pending
        activations must re-calculate them when this object is
        changed."
   DEFVAL      { {} }
   ::= { schedEntry 5 }

schedMonth 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 scheduled action should
        take place.  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.
        Note that implementations which maintain a list of pending
        activations must re-calculate them when this object is
        changed."
   DEFVAL      { {} }
   ::= { schedEntry 6 }

schedDay 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),
                   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 scheduled action
        should take place.  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.
        Note that implementations which maintain a list of pending
        activations must re-calculate them when this object is
        changed."
   DEFVAL      { {} }
   ::= { schedEntry 7 }

schedHour 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 scheduled
        action should take place.
        Note that implementations which maintain a list of pending
        activations must re-calculate them when this object is
        changed."
   DEFVAL      { {} }
   ::= { schedEntry 8 }

schedMinute 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 scheduled action
        should take place.
        Note that implementations which maintain a list of pending
        activations must re-calculate them when this object is
        changed."
   DEFVAL      { {} }
   ::= { schedEntry 9 }

schedContextName OBJECT-TYPE

   SYNTAX      SnmpAdminString (SIZE(0..32))
   MAX-ACCESS  read-create
   STATUS      current
   DESCRIPTION
       "The context which contains the local MIB variable pointed
        to by schedVariable."
   DEFVAL      { "" }
   ::= { schedEntry 10 }

schedVariable OBJECT-TYPE

   SYNTAX      VariablePointer
   MAX-ACCESS  read-create
   STATUS      current
   DESCRIPTION
       "An object identifier pointing to a local MIB variable
        which resolves to an ASN.1 primitive type of INTEGER."
   DEFVAL      { zeroDotZero }
   ::= { schedEntry 11 }

schedValue OBJECT-TYPE

   SYNTAX      Integer32
   MAX-ACCESS  read-create
   STATUS      current
   DESCRIPTION
       "The value which is written to the MIB object pointed to by
        schedVariable when the scheduler invokes an action.  The
        implementation shall enforce the use of access control
        rules when performing the set operation on schedVariable.
        This is accomplished by calling the isAccessAllowed abstract
        service interface as defined in RFC 2571.
        Note that an implementation may choose to issue an SNMP Set
        message to the SNMP engine and leave the access control
        decision to the normal message processing procedure."
   DEFVAL      { 0 }
   ::= { schedEntry 12 }

schedType OBJECT-TYPE

   SYNTAX      INTEGER {
                   periodic(1),
                   calendar(2),
                   oneshot(3)
               }
   MAX-ACCESS  read-create
   STATUS      current
   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 schedInterval.  The
        values of schedWeekDay, schedMonth, schedDay, schedHour
        and schedMinute are ignored.
        The value calendar(2) indicates that this entry describes a
        calendar schedule.  A calendar schedule is defined by the
        values of schedWeekDay, schedMonth, schedDay, schedHour and
        schedMinute.  The value of schedInterval is ignored.  A
        calendar schedule will trigger on all local times that
        satisfy the bits set in schedWeekDay, schedMonth, schedDay,
        schedHour and schedMinute.
        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'
        schedOperStatus once the schedule triggers an action.
        Note that implementations which maintain a list of pending
        activations must re-calculate them when this object is
        changed."
   DEFVAL      { periodic }
   ::= { schedEntry 13 }

schedAdminStatus OBJECT-TYPE

   SYNTAX      INTEGER {
                   enabled(1),
                   disabled(2)
               }
   MAX-ACCESS  read-create
   STATUS      current
   DESCRIPTION
       "The desired state of the schedule."
   DEFVAL      { disabled }
   ::= { schedEntry 14 }

schedOperStatus OBJECT-TYPE

   SYNTAX      INTEGER {
                   enabled(1),
                   disabled(2),
                   finished(3)
               }
   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.
        Note that the operational state must not be enabled(1)
        when the schedRowStatus is not active."
   ::= { schedEntry 15 }

schedFailures OBJECT-TYPE

   SYNTAX      Counter32
   MAX-ACCESS  read-only
   STATUS      current
   DESCRIPTION
       "This variable counts the number of failures while invoking
        the scheduled action.  This counter at most increments once
        for a triggered action."
   ::= { schedEntry 16 }

schedLastFailure OBJECT-TYPE

   SYNTAX      SnmpPduErrorStatus
   MAX-ACCESS  read-only
   STATUS      current
   DESCRIPTION
       "The most recent error that occurred during the invocation of
        a scheduled action.  The value noError(0) is returned
        if no errors have occurred yet."
   DEFVAL      { noError }
   ::= { schedEntry 17 }

schedLastFailed OBJECT-TYPE

   SYNTAX      DateAndTime
   MAX-ACCESS  read-only
   STATUS      current
   DESCRIPTION
       "The date and time when the most recent failure occurred.
        The value '0000000000000000'H is returned if no failure
        occurred since the last re-initialization of the scheduler."
   DEFVAL      { '0000000000000000'H }
   ::= { schedEntry 18 }

schedStorageType 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 schedDescr,
        schedInterval, schedContextName, schedVariable, schedValue,
        and schedAdminStatus.  If an implementation supports the
        schedCalendarGroup, write access must be also allowed to
        the columnar objects schedWeekDay, schedMonth, schedDay,
        schedHour, schedMinute."
   DEFVAL      { volatile }
   ::= { schedEntry 19 }

schedRowStatus OBJECT-TYPE

   SYNTAX      RowStatus
   MAX-ACCESS  read-create
   STATUS      current
   DESCRIPTION
       "The status of this scheduled action.  A control that allows
        entries to be added and removed from this table.
        Note that the operational state must change to enabled
        when the administrative state is enabled and the row
        status changes to active(1).
        Attempts to destroy(6) a row or to set a row
        notInService(2) while the operational state is enabled
        result in inconsistentValue errors.
        The value of this object has no effect on whether other
        objects in this conceptual row can be modified."
   ::= { schedEntry 20 }

schedTriggers OBJECT-TYPE

   SYNTAX      Counter32
   MAX-ACCESS  read-only
   STATUS      current
   DESCRIPTION
       "This variable counts the number of attempts (either
        successful or failed) to invoke the scheduled action."
   ::= { schedEntry 21 }

-- -- Notifications that are emitted to indicate failures. The -- definition of schedTraps makes notification registrations -- reversible (see STD 58, RFC 2578). --

schedTraps OBJECT IDENTIFIER ::= { schedNotifications 0 }

schedActionFailure NOTIFICATION-TYPE

   OBJECTS     { schedLastFailure, schedLastFailed }
   STATUS      current
   DESCRIPTION
       "This notification is generated whenever the invocation of a
        scheduled action fails."
   ::= { schedTraps 1 }

-- conformance information

schedCompliances OBJECT IDENTIFIER ::= { schedConformance 1 } schedGroups OBJECT IDENTIFIER ::= { schedConformance 2 }

-- compliance statements

schedCompliance2 MODULE-COMPLIANCE

   STATUS      current
   DESCRIPTION
       "The compliance statement for SNMP entities which implement
        the scheduling MIB."
   MODULE      -- this module
   MANDATORY-GROUPS {
          schedGroup2, schedNotificationsGroup
   }
   GROUP  schedCalendarGroup
   DESCRIPTION
       "The schedCalendarGroup is mandatory only for those
        implementations that support calendar based schedules."
   OBJECT schedType
   DESCRIPTION
       "The values calendar(2) or oneshot(3) are not valid for
        implementations that do not implement the
        schedCalendarGroup.  Such an implementation must return
        inconsistentValue error responses for attempts to set
        schedAdminStatus to calendar(2) or oneshot(3)."
   ::= { schedCompliances 2 }

schedGroup2 OBJECT-GROUP

   OBJECTS {
       schedDescr, schedInterval, schedContextName,
       schedVariable, schedValue, schedType,
       schedAdminStatus, schedOperStatus, schedFailures,
       schedLastFailure, schedLastFailed, schedStorageType,
       schedRowStatus, schedTriggers
   }
   STATUS      current
   DESCRIPTION
       "A collection of objects providing scheduling capabilities."
   ::= { schedGroups 4 }

schedCalendarGroup OBJECT-GROUP

   OBJECTS {
       schedLocalTime, schedWeekDay, schedMonth,
       schedDay, schedHour, schedMinute
   }
   STATUS      current
   DESCRIPTION
       "A collection of objects providing calendar based schedules."
   ::= { schedGroups 2 }

schedNotificationsGroup NOTIFICATION-GROUP

   NOTIFICATIONS {
       schedActionFailure
   }
   STATUS      current
   DESCRIPTION
       "The notifications emitted by the scheduler."
   ::= { schedGroups 3 }

-- -- Deprecated compliance and conformance group definitions -- from RFC 2591. --

schedCompliance MODULE-COMPLIANCE

   STATUS      deprecated
   DESCRIPTION
       "The compliance statement for SNMP entities which implement
        the scheduling MIB."
   MODULE      -- this module
   MANDATORY-GROUPS {
          schedGroup, schedNotificationsGroup
   }
   GROUP  schedCalendarGroup
   DESCRIPTION
       "The schedCalendarGroup is mandatory only for those
        implementations that support calendar based schedules."
   OBJECT schedType
   DESCRIPTION
       "The values calendar(2) or oneshot(3) are not valid for
        implementations that do not implement the
        schedCalendarGroup.  Such an implementation must return
        inconsistentValue error responses for attempts to set
        schedAdminStatus to calendar(2) or oneshot(3)."
   ::= { schedCompliances 1 }

schedGroup OBJECT-GROUP

   OBJECTS {
       schedDescr, schedInterval, schedContextName,
       schedVariable, schedValue, schedType,
       schedAdminStatus, schedOperStatus, schedFailures,
       schedLastFailure, schedLastFailed, schedStorageType,
       schedRowStatus
   }
   STATUS      deprecated
   DESCRIPTION
       "A collection of objects providing scheduling capabilities."
   ::= { schedGroups 1 }

END

Usage Examples

This section presents some examples how the scheduling MIB can be used to schedule scripts with the Script MIB RFC3165 or to realize on-duty/off-duty schedules by modifying status objects of other MIB modules.

Starting a script to ping devices every 20 minutes

It is assumed that the schedule entry is owned by schedOwner = "joe" and its name is schedName = "ping". The instance identifier for the scheduling entry is therefore 3.106.111.101.4.112.105.110.103.

It is further assumed that the smLaunchTable entry is owned by smLaunchOwner = "joe" and its name is smLaunchName = "ping-devs". The complete object identifier for the smLaunchStart object is therefore smLaunchStart.3.106.111.101.9.112.105.110.103.45.100.101.118.115. The script lives in the context identified by the string "engine1".

The configuration of the scheduler entry which launches the script every 20 minutes would look as follows:

  schedInterval.3.106.111.101.4.112.105.110.103 = 1200
  schedValue.3.106.111.101.4.112.105.110.103 = 0
  schedContextName.3.106.111.101.4.112.105.110.103 = "engine1"
  schedVariable.3.106.111.101.4.112.105.110.103 =
    smLaunchStart.3.106.111.101.9.112.105.110.103.45.100.101.118.115
  schedType.3.106.111.101.4.112.105.110.103 = periodic(1)
  schedAdminStatus.3.106.111.101.4.112.105.110.103 = enabled(1)
  schedStorageType.3.106.111.101.4.112.105.110.103 = nonVolatile(3)
  schedRowStatus.3.106.111.101.4.112.105.110.103 = active(1)

All the remaining columns in the schedTable represent status information and are not shown here.

Starting a script at the next Friday the 13th

It is assumed that the schedule entry is owned by schedOwner = "joe" and its name is schedName = "13th". The instance identifier for the scheduling entry is therefore 3.106.111.101.4.49.51.116.104.

It is further assumed that the smLaunchTable entry is owned by smLaunchOwner = "joe" and its name is smLaunchName = "ghost". The complete object identifier for the smLaunchStart object is therefore smLaunchStart.3.106.111.101.5.103.104.111.115.116. The script lives in the context identified by the string "engine1".

The configuration of the scheduler entry which launches the script on the next Friday 13th at midnight would look as follows:

  schedWeekDay.3.106.111.101.4.49.51.116.104 = { friday }
  schedMonth.3.106.111.101.4.49.51.116.104 = {
        january, february, march, april, may, june,
        july, august, september, october, november, december
  }
  schedDay.3.106.111.101.4.49.51.116.104 = { d13 }
  schedHour.3.106.111.101.4.49.51.116.104 = { h0 }
  schedMinute.3.106.111.101.4.49.51.116.104 = { m0 }
  schedValue.3.106.111.101.4.49.51.116.104 = 0
  schedContextName.3.106.111.101.4.49.51.116.104 = "engine1"
  schedVariable.3.106.111.101.4.49.51.116.104 =
    smLaunchStart.3.106.111.101.5.103.104.111.115.116
  schedType.3.106.111.101.4.49.51.116.104 = oneshot(3)
  schedAdminStatus.3.106.111.101.4.49.51.116.104 = enabled(2)
  schedStorageType.3.106.111.101.4.49.51.116.104 = nonVolatile(3)
  schedRowStatus.3.106.111.101.4.49.51.116.104 = active(1)

All the remaining columns in the schedTable represent status information and are not shown here.

Turning an interface off during weekends

This example assumes that a network interface should be taken down during weekends. The interface table (ifTable) of the IF-MIB RFC2863 is assumed to exist in the context identified by an empty string and the index of the interface is ifIndex = 6.

The scheduling entry which brings the interface down on every Friday evening at 20:30 (8:30 pm) is owned by schedOwner = "bob" and its name is schedName = "if-off". The instance identifier for the scheduling entry is therefore 3.98.111.98.6.105.102.45.111.102.102.

  schedWeekDay.3.98.111.98.6.105.102.45.111.102.102 = { friday }
  schedMonth.3.98.111.98.6.105.102.45.111.102.102 = {
        january, february, march, april, may, june,
        july, august, september, october, november, december
  }
  schedDay.3.98.111.98.6.105.102.45.111.102.102 = {
        d1, d2, d3, d4, d5, d6, d7, d8, d9, d10,
        d11, d12, d13, d14, d15, d16, d17, d18, d19, d20,
        d21, d22, d23, d24, d25, d26, d27, d28, d29, d30, d31
  }
  schedHour.3.98.111.98.6.105.102.45.111.102.102 = { h20 }
  schedMinute.3.98.111.98.6.105.102.45.111.102.102 = { m30 }
  schedValue.3.98.111.98.6.105.102.45.111.102.102 = down(2)
  schedContextName.3.98.111.98.6.105.102.45.111.102.102 = ""
  schedVariable.3.98.111.98.6.105.102.45.111.102.102 =
    ifAdminStatus.6
  schedType.3.98.111.98.6.105.102.45.111.102.102 = calendar(2)
  schedAdminStatus.3.98.111.98.6.105.102.45.111.102.102 = enabled(1)
  schedStorageType.3.98.111.98.6.105.102.45.111.102.102 =
    nonVolatile(3)
  schedRowStatus.3.98.111.98.6.105.102.45.111.102.102 = active(1)

The scheduling entry which brings the interface up on every Monday morning at 5:30 is owned by schedOwner = "bob" and its name is schedName = "if-on". The instance identifier for the scheduling entry is therefore 3.98.111.98.5.105.102.45.111.110.

The entry in the schedTable which brings the interface up again on every Monday morning at 5:30 looks as follows:

  schedWeekDay.3.98.111.98.5.105.102.45.111.110 = { monday }
  schedMonth.3.98.111.98.5.105.102.45.111.110 = {
        january, february, march, april, may, june,
        july, august, september, october, november, december
  }
  schedDay.3.98.111.98.5.105.102.45.111.110 = {
        d1, d2, d3, d4, d5, d6, d7, d8, d9, d10,
        d11, d12, d13, d14, d15, d16, d17, d18, d19, d20,
        d21, d22, d23, d24, d25, d26, d27, d28, d29, d30, d31
  }
  schedHour.3.98.111.98.5.105.102.45.111.110 = { h5 }
  schedMinute.3.98.111.98.5.105.102.45.111.110 = { m30 }
  schedValue.3.98.111.98.5.105.102.45.111.110 = up(1)
  schedContextName.3.98.111.98.5.105.102.45.111.110 = ""
  schedVariable.3.98.111.98.5.105.102.45.111.110 = ifAdminStatus.6
  schedType.3.98.111.98.5.105.102.45.111.110 = calendar(2)
  schedAdminStatus.3.98.111.98.5.105.102.45.111.110 = enabled(1)
  schedStorageType.3.98.111.98.5.105.102.45.111.110 = nonVolatile(3)
  schedRowStatus.3.98.111.98.5.105.102.45.111.110 = active(1)

A similar configuration could be used to control other schedules. For example, one could change the "if-on" and "if-off" schedules to enable and disable the periodic scheduler defined in the first example.

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 implementers consider the security features as provided by the SNMPv3 framework. Specifically, the use of the User-based Security Model RFC 2574 RFC2574 and the View- based Access Control Model RFC 2575 RFC2575 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.

Scheduled SNMP set operations must use the security credentials that were present when the corresponding row in the scheduling entry was created. An implementation must therefore record and maintain the credentials for every scheduling entry.

An implementation must ensure that access control rules are applied when doing the set operation. This is accomplished by calling the isAccessAllowed abstract service interface defined in RFC 2571 RFC2571:

  statusInformation =          -- success or errorIndication
    isAccessAllowed(
    IN   securityModel         -- Security Model in use
    IN   securityName          -- principal who wants to access
    IN   securityLevel         -- Level of Security
    IN   viewType              -- read, write, or notify view
    IN   contextName           -- context containing variableName
    IN   variableName          -- OID for the managed object
         )

The securityModel, securityName and securityLevel parameters are set to the values that were recorded when the scheduling entry was created. The viewType parameter must select the write view and the contextName and variableName parameters are taken from the schedContextName and schedVariableName values of the scheduling entry.

This MIB limits scheduled actions to objects in the local MIB. This avoids security problems with the delegation of access rights. However, it might be possible for a user of this MIB to own some schedules that might trigger far in the future. This can cause security risks if the security administrator did not properly update the access control lists when a user is withdrawn from an SNMP engine. Therefore, entries in the schedTable SHOULD be cleaned up whenever a user is removed from an SNMP engine.

To facilitate the provisioning of access control by a security administrator using the View-Based Access Control Model (VACM) defined in RFC 2575 RFC2575 for tables in which multiple users may need to independently create or modify entries, the initial index is used as an "owner index". Such an initial index has a syntax of

SnmpAdminString, and can thus be trivially mapped to a securityName or groupName as defined in VACM, in accordance with a security policy.

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

Intellectual Property

The IETF takes no position regarding the validity or scope of any intellectual property or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; neither does it represent that it has made any effort to identify any such rights. Information on the IETF's procedures with respect to rights in standards-track and standards-related documentation can be found in BCP 11, RFC 2028. 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.

Changes from RFC 2591

The following list documents major changes from the previous version of this document, published as RFC 2591:

- Updated the SNMP Management Framework boilerplate and the

  references.

- Added revision clauses to the module identity macro.

- Clarified the behavior during time transitions.

- Clarified that schedInterval and schedCalendarGroup objects can be

  modified regardless of the current value of schedRowStatus,
  schedAdminStatus and schedOperStatus.

- Added some additional boilerplate text to the security

  considerations section.

- Clarified that implementations must re-calculate any pending

  action invocations when scheduling parameters are modified.

- Clarified that schedOperStatus must not be enabled while the

  schedRowStatus is not active.

- Clarified that schedRowStatus can not be changed as long as the

  schedOperStatus is enabled.

- Clarified that implementations can delegate the isAccessAllowed

  check by sending themself an SNMP Set message.

- Added the schedTriggers object which counts the total number of

  triggers.

- Added DEFVALs for schedContextName, schedVariable, and schedValue

  and updated the schedRowStatus description.

- Deprecated schedCompliance, schedGroup and created

  schedCompliance2 and schedGroup2 that take care of the new
  schedTriggers object.

Acknowledgments

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

10. References

RFC2571 Harrington, D., Presuhn, R. and B. Wijnen, "An

          Architecture for Describing SNMP Management Frameworks",
          RFC 2571, April 1999.

RFC1155 Rose, M. and K. McCloghrie, "Structure and Identification

          of Management Information for TCP/IP-based Internets", STD
          16, RFC 1155, May 1990.

RFC1212 Rose, M. and K. McCloghrie, "Concise MIB Definitions", STD

          16, RFC 1212, March 1991.

RFC1215 Rose, M., "A Convention for Defining Traps for use with

          the SNMP", RFC 1215, March 1991.

RFC2578 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.

RFC2579 McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,

          Rose, M. and S. Waldbusser, "Textual Conventions for
          SMIv2", STD 58, RFC 2579, April 1999.

RFC2580 McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,

          Rose, M. and S. Waldbusser, "Conformance Statements for
          SMIv2", STD 58, RFC 2580, April 1999.

RFC1157 Case, J., Fedor, M., Schoffstall, M. and J. Davin, "Simple

          Network Management Protocol", STD 15, RFC 1157, May 1990.

RFC1901 Case, J., McCloghrie, K., Rose, M. and S. Waldbusser,

          "Introduction to Community-based SNMPv2", RFC 1901,
          January 1996.

RFC1906 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.

RFC2572 Case, J., Harrington D., Presuhn R. and B. Wijnen,

          "Message Processing and Dispatching for the Simple Network
          Management Protocol (SNMP)", RFC 2572, April 1999.

RFC2574 Blumenthal, U. and B. Wijnen, "User-based Security Model

          (USM) for version 3 of the Simple Network Management
          Protocol (SNMPv3)", RFC 2574, April 1999.

RFC1905 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.

RFC2573 Levi, D., Meyer, P. and B. Stewart, "SNMPv3 Applications",

          RFC 2573, April 1999.

RFC2575 Wijnen, B., Presuhn, R. and K. McCloghrie, "View-based

          Access Control Model (VACM) for the Simple Network
          Management Protocol (SNMP)", RFC 2575, April 1999.

RFC2570 Case, J., Mundy, R., Partain, D. and B. Stewart,

          "Introduction to Version 3 of the Internet-standard
          Network Management Framework", RFC 2570, April 1999.

RFC2028 Hovey, R. and S. Bradner, "The Organizations Involved in

          the IETF Standards Process", BCP 11, RFC 2028, October
          1996.

RFC3165 Levi, D. and J. Schoenwaelder, "Definitions of Managed

          Objects for the Delegation of Management Scripts", RFC
          3165, August 2001.

RFC2863 McCloghrie, K. and F. Kastenholz, "The Interfaces Group

          MIB", RFC 2863, June 2000.

RFC2119 Bradner, S., "Key words for use in RFCs to Indicate

          Requirement Levels", BCP 14, RFC 2119, March 1997.

11. Editors' Addresses

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

Phone: +1 865 686 0432 EMail: [email protected]

Juergen Schoenwaelder TU Braunschweig Bueltenweg 74/75 38106 Braunschweig Germany

Phone: +49 531 391-3283 EMail: [email protected]

12. Full Copyright Statement

Copyright (C) The Internet Society (2002). All Rights Reserved.

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

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

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

Acknowledgement

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