Network Working Group                                        S. Chisholm
Request for Comments: 4268                               Nortel Networks
Category: Standards Track                                     D. Perkins
                                                               SNMPinfo
                                                          November 2005


                           Entity State MIB

Status of This Memo

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

Copyright Notice

  Copyright (C) The Internet Society (2005).

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 extensions to the Entity MIB to provide
  information about the state of physical entities.

  In addition, this memo defines a set of Textual Conventions to
  represent various states of an entity.  The intent is that these
  Textual Conventions will be imported and used in MIB modules that
  would otherwise define their own representations.

Table of Contents

  1. The Internet-Standard Management Framework ......................2
  2. Entity State ....................................................2
     2.1. Hierarchical State Management ..............................3
     2.2. Entity Redundancy ..........................................3
     2.3. Physical Entity Users ......................................3
     2.4. Physical Class Behavior ....................................4
  3. Relation to Other MIBs ..........................................4
     3.1. Relation to the Interfaces MIB .............................4
     3.2. Relation to Alarm MIB ......................................5
     3.3. Relation to Bridge MIB .....................................5
     3.4. Relation to the Host Resources MIB .........................5
  4. Textual Conventions .............................................6
  5. Definitions .................................................... 9



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  6. Security Considerations ........................................16
  7. Acknowledgements ...............................................17
  8. References .....................................................17
     8.1. Normative References ......................................17
     8.2. Informative References ....................................18

1.  The Internet-Standard Management Framework

  For a detailed overview of the documents that describe the current
  Internet-Standard Management Framework, please refer to section 7 of
  RFC 3410 [RFC3410].

  Managed objects are accessed via a virtual information store, termed
  the Management Information Base or MIB.  MIB objects are generally
  accessed through the Simple Network Management Protocol (SNMP).
  Objects in the MIB are defined using the mechanisms defined in the
  Structure of Management Information (SMI).  This memo specifies a MIB
  module that is compliant to the SMIv2, which is described in STD 58,
  RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580
  [RFC2580].

2.  Entity State

  The goal in adding state objects to the Entity MIB [RFC4133] is to
  define a useful subset of the possible state attributes that could be
  tracked for a given entity and that both fit into the state models
  such as those used in the Interfaces MIB [RFC2863] as well as
  leverage existing well-deployed models.  The entStateTable contains
  state objects that are a subset of the popular ISO/OSI states that
  are also defined in ITU's X.731 specification [X.731].  Objects are
  defined to capture administrative, operational, and usage states.  In
  addition, there are further state objects defined to provide more
  information for these three basic states.

  Administrative state indicates permission to use or prohibition
  against using the entity and is imposed through the management
  services.

  Operational state indicates whether or not the entity is physically
  installed and working.  Note that unlike the ifOperStatus [RFC2863],
  this operational state is independent of the administrative state.

  Usage state indicates whether or not the entity is in use at a
  specific instance, and if so, whether or not it currently has spare
  capacity to serve additional users.  In the context of this MIB, the
  usage state refers to the ability of an entity to service other
  entities within its containment hierarchy.




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  Alarm state indicates whether or not there are any alarms active
  against the entity.  In addition to those alarm states defined in
  X.731 [X.731], warning and indeterminate status are also defined to
  provide a more complete mapping to the Alarm MIB [RFC3877].

  Standby state indicates whether the entity is currently running as
  hot standby or cold standby or is currently providing service.

  The terms "state" and "status" are used interchangeably in this memo.

  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].

2.1.  Hierarchical State Management

  Physical entities exist within a containment hierarchy.  Physical
  containment is defined by the entPhysicalContainedIn object[RFC4133].
  This raises some interesting issues not addressed in existing work on
  state management.

  There are two types of state for an entity:

  1) The state of the entity independent of the states of its parents
  and children in its containment hierarchy.  This is often referred to
  as raw state.

  2) The state of the entity, as it may be influenced by the state of
  its parents and children.  This is often referred to as computed
  state.

  All state objects in this memo are raw state.

2.2.  Entity Redundancy

  While this memo is not attempting to address the entire problem space
  around redundancy, the entStateStandby object provides an important
  piece of state information for entities, which helps identify which
  pieces of redundant equipment are currently providing service, and
  which are waiting in either hot or cold standby mode.

2.3.  Physical Entity Users

  There are three ways to define the 'user' of a physical entity

  1. Direct containment in physical hierarchy

  2. Anywhere in physical hierarchy



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  3. As defined by a means outside the scope of this MIB.  This could
  include logical interfaces that could run on a port, software that
  could run on a module, etc.

  Administrative, operational, alarm, and standby state use all three
  definitions of 'user'.  Usage state supports only the concept of
  direct containment to simplify implementations of this object.

2.4.  Physical Class Behavior

  This MIB makes no effort to standardize the behaviors and
  characteristics of the various physical classes [RFC4133], but rather
  how this information is reported.  In looking at real-world products,
  items within the same physical class vary substantially.  The MIB has
  therefore provided guidance on how to support objects where a
  particular instance of a physical class cannot support part or all of
  a particular state.

3.  Relation to Other MIBs

3.1.  Relation to the Interfaces MIB

  The Interfaces MIB [RFC2863] defines the ifAdminStatus object, which
  has states of up, down, and testing, and the ifOperStatus object,
  which has states of up, down, testing, unknown, dormant, notPresent,
  and lowerLayerDown.

  An ifAdminStatus of 'up' is equivalent to setting the entStateAdmin
  object to 'unlocked'.  An ifAdminStatus of 'down' is equivalent to
  setting the entStateAdmin object to either 'locked' or
  'shuttingDown', depending on a system's interpretation of 'down'.

  An ifOperStatus of 'up' is equivalent to an entStateOper value of
  'enabled'.  An ifOperStatus of 'down' due to operational failure is
  equivalent to an entStateOper value of 'disabled'.  An ifOperStatus
  of 'down' due to being administratively disabled is equivalent to an
  entStateAdmin value of 'locked' and an entStateOper value of either
  'enabled' or 'disabled' depending on whether there are any known
  issues that would prevent the entity from becoming operational when
  its entStateAdmin is set to 'unlocked'.  An ifOperStatus of 'unknown'
  is equivalent to an entStateOper value of 'unknown'.  The
  ifOperStatus values of 'testing' and 'dormant' are not explicitly
  supported by this MIB, but the state objects will be able to reflect
  other aspects of the entities' administrative and operational state.
  The ifOperStatus values of 'notPresent' and 'lowerLayerDown' are in
  some ways computed states and so are therefore not supported in this





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  MIB.  They can, though, be computed by examining the states of
  entities within this object's containment hierarchy and other
  available related states.

3.2.  Relation to Alarm MIB

  The entStateAlarm object indicates whether or not there are any
  active alarms against this entity.  If there are active alarms, then
  the alarmActiveTable in the Alarm MIB [RFC3877] should be searched
  for rows whose alarmActiveResourceId matches this entPhysicalIndex.

  Alternatively, if the alarmActiveTable is queried first and an active
  alarm with a value of alarmActiveResourceId that matches this
  entPhysicalIndex is found, then entStateAlarm can be used to quickly
  determine if there are additional active alarms with a different
  severity against this physical entity.

3.3 Relation to Bridge MIB

  For entities of physical type of 'port' that support the
  dot1dStpPortEnable object in the Bridge MIB [RFC4188], a value of
  'enabled' is equivalent to setting the entStateAdmin object to
  'unlocked'.  Setting dot1dStpPortEnable to 'disabled' is equivalent
  to setting the entStateAdmin object to 'locked'.

3.4 Relation to the Host Resources MIB

  The hrDeviceStatus object in the Host Resources MIB [RFC2790]
  provides an operational state for devices.  For entities that
  logically correspond to the concept of a device, a value of 'unknown'
  for hrDeviceStatus corresponds to an entStateOper value of 'unknown'.
  A value of 'running' corresponds to an entStateOper value of
  'enabled'.  A value of 'warning' also corresponds to an entStateOper
  value of 'enabled', but with appropriate bits set in the
  entStateAlarm object to indicate the alarms corresponding to the
  unusual error condition detected.  A value of 'testing' or 'down' is
  equivalent to an entStateOper value of 'disabled'.














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4.  Textual Conventions

  ENTITY-STATE-TC-MIB DEFINITIONS ::= BEGIN

  IMPORTS
     MODULE-IDENTITY, mib-2       FROM SNMPv2-SMI
     TEXTUAL-CONVENTION           FROM SNMPv2-TC;

   entityStateTc MODULE-IDENTITY
       LAST-UPDATED "200511220000Z"
       ORGANIZATION "IETF Entity MIB Working Group"
       CONTACT-INFO
               "General Discussion: [email protected]
                To Subscribe:
                http://www.ietf.org/mailman/listinfo/entmib

                http://www.ietf.org/html.charters/entmib-charter.html

                Sharon Chisholm
                Nortel Networks
                PO Box 3511 Station C
                Ottawa, Ont.  K1Y 4H7
                Canada
                [email protected]

                David T. Perkins
                548 Qualbrook Ct
                San Jose, CA 95110
                USA
                Phone: 408 394-8702
                [email protected]"
        DESCRIPTION
               "This MIB defines state textual conventions.

                Copyright (C) The Internet Society 2005.  This version
                of this MIB module is part of RFC 4268;  see the RFC
                itself for full legal notices."
        REVISION    "200511220000Z"
        DESCRIPTION
            "Initial version, published as RFC 4268."
       ::= { mib-2 130 }

    EntityAdminState  ::=  TEXTUAL-CONVENTION
      STATUS         current
      DESCRIPTION
           " Represents the various possible administrative states.





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             A value of 'locked' means the resource is administratively
             prohibited from use.  A value of 'shuttingDown' means that
             usage is administratively limited to current instances of
             use.  A value of 'unlocked' means the resource is not
             administratively prohibited from use.  A value of
             'unknown' means that this resource is unable to
             report administrative state."
      SYNTAX         INTEGER
                {
                unknown (1),
                locked (2),
                shuttingDown (3),
                unlocked (4)
                }

    EntityOperState  ::=  TEXTUAL-CONVENTION
      STATUS         current
      DESCRIPTION
           " Represents the possible values of operational states.

             A value of 'disabled' means the resource is totally
             inoperable.  A value of 'enabled' means the resource
             is partially or fully operable.  A value of 'testing'
             means the resource is currently being tested
             and cannot therefore report whether it is operational
             or not.  A value of 'unknown' means that this
             resource is unable to report operational state."
      SYNTAX         INTEGER
                {
                unknown (1),
                disabled (2),
                enabled (3),
                testing (4)
                }

    EntityUsageState  ::=  TEXTUAL-CONVENTION
      STATUS         current
      DESCRIPTION
           " Represents the possible values of usage states.
             A value of 'idle' means the resource is servicing no
             users.  A value of 'active' means the resource is
             currently in use and it has sufficient spare capacity
             to provide for additional users.  A value of 'busy'
             means the resource is currently in use, but it
             currently has no spare capacity to provide for
             additional users.  A value of 'unknown' means
             that this resource is unable to report usage state."
      SYNTAX         INTEGER



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                {
                unknown (1),
                idle (2),
                active (3),
                busy (4)
                }


   EntityAlarmStatus  ::=  TEXTUAL-CONVENTION
      STATUS         current
      DESCRIPTION
         " Represents the possible values of alarm status.
           An Alarm [RFC3877] is a persistent indication
           of an error or warning condition.

           When no bits of this attribute are set, then no active
           alarms are known against this entity and it is not under
           repair.

           When the 'value of underRepair' is set, the resource is
           currently being repaired, which, depending on the
           implementation, may make the other values in this bit
           string not meaningful.

           When the value of 'critical' is set, one or more critical
           alarms are active against the resource.  When the value
           of 'major' is set, one or more major alarms are active
           against the resource.  When the value of 'minor' is set,
           one or more minor alarms are active against the resource.
           When the value of 'warning' is set, one or more warning
           alarms are active against the resource.  When the value
           of 'indeterminate' is set, one or more alarms of whose
           perceived severity cannot be determined are active
           against this resource.

           A value of 'unknown' means that this resource is
           unable to report alarm state."
            SYNTAX         BITS
               {
               unknown (0),
               underRepair (1),
               critical(2),
               major(3),
               minor(4),
               -- The following are not defined in X.733
               warning (5),
               indeterminate (6)
                             }



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    EntityStandbyStatus  ::=  TEXTUAL-CONVENTION
      STATUS         current
      DESCRIPTION
           " Represents the possible values of standby status.

             A value of 'hotStandby' means the resource is not
             providing service, but it will be immediately able to
             take over the role of the resource to be backed up,
             without the need for initialization activity, and will
             contain the same information as the resource to be
             backed up.  A value of 'coldStandy' means that the
             resource is to back up another resource, but will not
             be immediately able to take over the role of a resource
             to be backed up, and will require some initialization
             activity.  A value of 'providingService' means the
             resource is providing service.  A value of
             'unknown' means that this resource is unable to
             report standby state."
            SYNTAX         INTEGER
              {
              unknown (1),
              hotStandby (2),
              coldStandby (3),
              providingService (4)
              }

  END

5.  Definitions

  ENTITY-STATE-MIB DEFINITIONS ::= BEGIN

    IMPORTS
        MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE, mib-2
            FROM SNMPv2-SMI
        DateAndTime
            FROM SNMPv2-TC
        MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
             FROM SNMPv2-CONF
        entPhysicalIndex
             FROM ENTITY-MIB
        EntityAdminState, EntityOperState, EntityUsageState,
        EntityAlarmStatus, EntityStandbyStatus
             FROM ENTITY-STATE-TC-MIB;

    entityStateMIB MODULE-IDENTITY
        LAST-UPDATED "200511220000Z"
        ORGANIZATION "IETF Entity MIB Working Group"



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        CONTACT-INFO
                " General Discussion: [email protected]
                  To Subscribe:
                  http://www.ietf.org/mailman/listinfo/entmib

                  http://www.ietf.org/html.charters/entmib-charter.html

                  Sharon Chisholm
                  Nortel Networks
                  PO Box 3511 Station C
                  Ottawa, Ont.  K1Y 4H7
                  Canada
                  [email protected]

                  David T. Perkins
                  548 Qualbrook Ct
                  San Jose, CA 95110
                  USA
                  Phone: 408 394-8702
                  [email protected]
                 "
        DESCRIPTION
            "This MIB defines a state extension to the Entity MIB.

             Copyright (C) The Internet Society 2005.  This version
             of this MIB module is part of RFC 4268; see the RFC
             itself for full legal notices."
        REVISION    "200511220000Z"
        DESCRIPTION
            "Initial version, published as RFC 4268."
        ::= { mib-2 131 }


    -- Entity State Objects

    entStateObjects OBJECT IDENTIFIER ::= { entityStateMIB 1 }

    entStateTable OBJECT-TYPE
     SYNTAX      SEQUENCE OF EntStateEntry
     MAX-ACCESS  not-accessible
     STATUS      current
     DESCRIPTION
         "A table of information about state/status of entities.
          This is a sparse augment of the entPhysicalTable.  Entries
          appear in this table for values of
          entPhysicalClass [RFC4133] that in this implementation
          are able to report any of the state or status stored in
          this table.



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          "
     ::= { entStateObjects 1 }


      entStateEntry OBJECT-TYPE
         SYNTAX      EntStateEntry
         MAX-ACCESS  not-accessible
         STATUS      current
         DESCRIPTION
             "State information about this physical entity."
         INDEX       { entPhysicalIndex }
         ::= { entStateTable 1 }

      EntStateEntry ::= SEQUENCE {
          entStateLastChanged DateAndTime,
          entStateAdmin       EntityAdminState,
          entStateOper        EntityOperState,
          entStateUsage       EntityUsageState,
          entStateAlarm       EntityAlarmStatus,
          entStateStandby     EntityStandbyStatus
         }

    entStateLastChanged OBJECT-TYPE
     SYNTAX      DateAndTime
     MAX-ACCESS  read-only
     STATUS      current
     DESCRIPTION
       "The value of this object is the date and
        time when the value of any of entStateAdmin,
        entStateOper, entStateUsage, entStateAlarm,
        or entStateStandby changed for this entity.

        If there has been no change since
        the last re-initialization of the local system,
        this object contains the date and time of
        local system initialization.  If there has been
        no change since the entity was added to the
        local system, this object contains the date and
        time of the insertion."
     ::= { entStateEntry 1 }

  entStateAdmin OBJECT-TYPE
         SYNTAX      EntityAdminState
         MAX-ACCESS  read-write
         STATUS      current
         DESCRIPTION
              "The administrative state for this entity.




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               This object refers to an entities administrative
               permission to service both other entities within
               its containment hierarchy as well other users of
               its services defined by means outside the scope
               of this MIB.

               Setting this object to 'notSupported' will result
               in an 'inconsistentValue' error.  For entities that
               do not support administrative state, all set
               operations will result in an 'inconsistentValue'
               error.

               Some physical entities exhibit only a subset of the
               remaining administrative state values.  Some entities
               cannot be locked, and hence this object exhibits only
               the 'unlocked' state.  Other entities cannot be shutdown
               gracefully, and hence this object does not exhibit the
               'shuttingDown' state.  A value of 'inconsistentValue'
               will be returned if attempts are made to set this
               object to values not supported by its administrative
               model."
         ::= { entStateEntry 2 }

   entStateOper OBJECT-TYPE
         SYNTAX      EntityOperState
         MAX-ACCESS  read-only
         STATUS      current
         DESCRIPTION
             "The operational state for this entity.

              Note that unlike the state model used within the
              Interfaces MIB [RFC2863], this object does not follow
              the administrative state.  An administrative state of
              down does not predict an operational state
              of disabled.

              A value of 'testing' means that entity currently being
              tested and cannot therefore report whether it is
              operational or not.

              A value of 'disabled' means that an entity is totally
              inoperable and unable to provide service both to entities
              within its containment hierarchy, or to other receivers
              of its service as defined in ways outside the scope of
              this MIB.

              A value of 'enabled' means that an entity is fully or
              partially operable and able to provide service both to



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RFC 4268                    Entity State MIB               November 2005


              entities within its containment hierarchy, or to other
              receivers of its service as defined in ways outside the
              scope of this MIB.

              Note that some implementations may not be able to
              accurately report entStateOper while the
              entStateAdmin object has a value other than 'unlocked'.
              In these cases, this object MUST have a value
              of 'unknown'."
         ::= { entStateEntry 3 }

   entStateUsage OBJECT-TYPE
         SYNTAX      EntityUsageState
         MAX-ACCESS  read-only
         STATUS      current
         DESCRIPTION
             "The usage state for this entity.

              This object refers to an entity's ability to service more
              physical entities in a containment hierarchy.  A value
              of 'idle' means this entity is able to contain other
              entities but that no other entity is currently
              contained within this entity.

              A value of 'active' means that at least one entity is
              contained within this entity, but that it could handle
              more.  A value of 'busy' means that the entity is unable
              to handle any additional entities being contained in it.

              Some entities will exhibit only a subset of the
              usage state values.  Entities that are unable to ever
              service any entities within a containment hierarchy will
              always have a usage state of 'busy'.  Some entities will
              only ever be able to support one entity within its
              containment hierarchy and will therefore only exhibit
              values of 'idle' and 'busy'."
            ::= { entStateEntry 4 }

   entStateAlarm OBJECT-TYPE
         SYNTAX      EntityAlarmStatus
         MAX-ACCESS  read-only
         STATUS      current
         DESCRIPTION
             "The alarm status for this entity.  It does not include
              the alarms raised on child components within its
              containment hierarchy.

              A value of 'unknown' means that this entity is



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RFC 4268                    Entity State MIB               November 2005


              unable to report alarm state.  Note that this differs
              from 'indeterminate', which means that alarm state
              is supported and there are alarms against this entity,
              but the severity of some of the alarms is not known.

              If no bits are set, then this entity supports reporting
              of alarms, but there are currently no active alarms
              against this entity."
         ::= { entStateEntry 5 }

  entStateStandby OBJECT-TYPE
         SYNTAX EntityStandbyStatus
         MAX-ACCESS read-only
         STATUS current
         DESCRIPTION
              "The standby status for this entity.

              Some entities will exhibit only a subset of the
              remaining standby state values.  If this entity
              cannot operate in a standby role, the value of this
              object will always be 'providingService'."
    ::= { entStateEntry 6 }

  -- Notifications
   entStateNotifications OBJECT IDENTIFIER ::= { entityStateMIB 0 }

  entStateOperEnabled NOTIFICATION-TYPE
     OBJECTS { entStateAdmin,
               entStateAlarm
             }
     STATUS             current
     DESCRIPTION
             "An entStateOperEnabled notification signifies that the
              SNMP entity, acting in an agent role, has detected that
              the entStateOper object for one of its entities has
              transitioned into the 'enabled' state.

              The entity this notification refers can be identified by
              extracting the entPhysicalIndex from one of the
              variable bindings.  The entStateAdmin and entStateAlarm
              varbinds may be examined to find out additional
              information on the administrative state at the time of
              the operation state change as well as to find out whether
              there were any known alarms against the entity at that
              time that may explain why the physical entity has become
              operationally disabled."
    ::= { entStateNotifications 1 }




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RFC 4268                    Entity State MIB               November 2005


  entStateOperDisabled NOTIFICATION-TYPE
     OBJECTS { entStateAdmin,
               entStateAlarm }
     STATUS             current
     DESCRIPTION
             "An entStateOperDisabled notification signifies that the
              SNMP entity, acting in an agent role, has detected that
              the entStateOper object for one of its entities has
              transitioned into the 'disabled' state.

              The entity this notification refers can be identified by
              extracting the entPhysicalIndex from one of the
              variable bindings.  The entStateAdmin and entStateAlarm
              varbinds may be examined to find out additional
              information on the administrative state at the time of
              the operation state change as well as to find out whether
              there were any known alarms against the entity at that
              time that may affect the physical entity's
              ability to stay operationally enabled."
    ::= { entStateNotifications 2 }

  -- Conformance and Compliance

  entStateConformance OBJECT IDENTIFIER ::= { entityStateMIB 2 }

  entStateCompliances OBJECT IDENTIFIER
                    ::= { entStateConformance 1 }

  entStateCompliance MODULE-COMPLIANCE
        STATUS  current
        DESCRIPTION
            "The compliance statement for systems supporting
            the Entity State MIB."
        MODULE -- this module
            MANDATORY-GROUPS {
             entStateGroup
            }
        GROUP       entStateNotificationsGroup
           DESCRIPTION
               "This group is optional."
        OBJECT entStateAdmin
         MIN-ACCESS  read-only
         DESCRIPTION
             "Write access is not required."
     ::= { entStateCompliances 1 }

  entStateGroups OBJECT IDENTIFIER ::= { entStateConformance 2 }




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  entStateGroup OBJECT-GROUP
     OBJECTS {
             entStateLastChanged,
             entStateAdmin,
             entStateOper,
             entStateUsage,
             entStateAlarm,
             entStateStandby
             }
      STATUS   current
      DESCRIPTION
           "Standard Entity State group."
      ::= { entStateGroups 1}

  entStateNotificationsGroup NOTIFICATION-GROUP
     NOTIFICATIONS {
             entStateOperEnabled,
             entStateOperDisabled
             }
      STATUS   current
      DESCRIPTION
           "Standard Entity State Notification group."
      ::= { entStateGroups 2}

  END

6.  Security Considerations

  The ENTITY-STATE-TC-MIB defined in section 4 does not define any
  management objects.  Instead, it defines a set of textual conventions
  that may be used by other MIB modules to define management objects.
  Meaningful security considerations can only be written in the MIB
  modules that define management objects.  The ENTITY-STATE-TC-MIB has
  therefore no impact on the security of the Internet.

  The ENTITY-STATE-MIB defined in section 5 defines one management
  object -- entStateAdmin -- that has a MAX-ACCESS clause of read-
  write.  The object 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.

  Note that setting the entStateAdmin to 'locked' or 'shuttingDown' can
  cause disruption of services ranging from those running on a port to
  those on an entire device, depending on the type of entity.  Access
  to this object should be properly protected.





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RFC 4268                    Entity State MIB               November 2005


  Access to the objects defined in this MIB allows one to figure out
  what the active and standby resources in a network are.  This
  information can be used to optimize attacks on networks so even
  read-only access to this MIB should be properly protected.

  SNMP versions prior to SNMPv3 did not include adequate security.
  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 module.

  It is RECOMMENDED that implementers consider the security features as
  provided by the SNMPv3 framework (see [RFC3410], section 8),
  including full support for the SNMPv3 cryptographic mechanisms (for
  authentication and privacy).

  Further, deployment of SNMP versions prior to SNMPv3 is NOT
  RECOMMENDED.  Instead, it is RECOMMENDED to deploy SNMPv3 and to
  enable cryptographic security.  It is then a customer/operator
  responsibility to ensure that the SNMP entity giving access to an
  instance of this MIB module is properly configured to give access to
  the objects only to those principals (entities) that have legitimate
  rights to indeed GET or SET (change/create/delete) them.

7.  Acknowledgements

  This document is a product of the Entity MIB Working Group.

8.  References

8.1.  Normative References

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997.

  [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.




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RFC 4268                    Entity State MIB               November 2005


  [RFC4133]  Bierman, A. and K. McCloghrie, "Entity MIB (Version 3)",
             RFC 4133, August 2005.

8.2.  Informative References

  [RFC2790]  Waldbusser, S. and P. Grillo, "Host Resources MIB", RFC
             2790, March 2000.

  [RFC2863]  McCloghrie, K. and F. Kastenholz, "The Interfaces Group
             MIB using SMIv2", RFC 2863, June 2000.

  [RFC3410]  Case, J., Mundy, R., Partain, D., and B. Stewart,
             "Introduction and Applicability Statements for Internet-
             Standard Management Framework", RFC 3410, December 2002.

  [RFC3877]  Chisholm, S. and D. Romascanu, "Alarm Management
             Information Base (MIB)", RFC 3877, September 2004.

  [RFC4188]  Norseth, K. and E. Bell, "Definitions of Managed Objects
             for Bridges", RFC 4188, September 2005.

  [X.731]    ITU Recommendation X.731, "Information Technology - Open
             Systems Interconnection - System Management: State
             Management Function", 1992.

Authors' Addresses

  Sharon Chisholm
  Nortel Networks
  PO Box 3511, Station C
  Ottawa, Ontario, K1Y 4H7
  Canada

  EMail: [email protected]


  David T. Perkins
  548 Qualbrook Ct
  San Jose, CA 95110
  USA

  Phone: 408 394-8702
  EMail: [email protected]








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RFC 4268                    Entity State MIB               November 2005


Full Copyright Statement

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  contained in BCP 78, and except as set forth therein, the authors
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Acknowledgement

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