956 lines
38 KiB
Plaintext
956 lines
38 KiB
Plaintext
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SNMPv2-TC DEFINITIONS ::= BEGIN
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IMPORTS
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TimeTicks FROM SNMPv2-SMI;
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DisplayString ::= TEXTUAL-CONVENTION
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DISPLAY-HINT "255a"
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STATUS current
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DESCRIPTION
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"Represents textual information taken from the NVT ASCII
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McCloghrie, et al. Standards Track [Page 3]
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RFC 2579 Textual Conventions for SMIv2 April 1999
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character set, as defined in pages 4, 10-11 of RFC 854.
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To summarize RFC 854, the NVT ASCII repertoire specifies:
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- the use of character codes 0-127 (decimal)
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- the graphics characters (32-126) are interpreted as
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US ASCII
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- NUL, LF, CR, BEL, BS, HT, VT and FF have the special
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meanings specified in RFC 854
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- the other 25 codes have no standard interpretation
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- the sequence 'CR LF' means newline
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- the sequence 'CR NUL' means carriage-return
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- an 'LF' not preceded by a 'CR' means moving to the
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same column on the next line.
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- the sequence 'CR x' for any x other than LF or NUL is
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illegal. (Note that this also means that a string may
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end with either 'CR LF' or 'CR NUL', but not with CR.)
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Any object defined using this syntax may not exceed 255
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characters in length."
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SYNTAX OCTET STRING (SIZE (0..255))
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PhysAddress ::= TEXTUAL-CONVENTION
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DISPLAY-HINT "1x:"
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STATUS current
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DESCRIPTION
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"Represents media- or physical-level addresses."
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SYNTAX OCTET STRING
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MacAddress ::= TEXTUAL-CONVENTION
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DISPLAY-HINT "1x:"
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STATUS current
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DESCRIPTION
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"Represents an 802 MAC address represented in the
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`canonical' order defined by IEEE 802.1a, i.e., as if it
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were transmitted least significant bit first, even though
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802.5 (in contrast to other 802.x protocols) requires MAC
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addresses to be transmitted most significant bit first."
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SYNTAX OCTET STRING (SIZE (6))
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TruthValue ::= TEXTUAL-CONVENTION
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STATUS current
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DESCRIPTION
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"Represents a boolean value."
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SYNTAX INTEGER { true(1), false(2) }
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TestAndIncr ::= TEXTUAL-CONVENTION
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STATUS current
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DESCRIPTION
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"Represents integer-valued information used for atomic
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operations. When the management protocol is used to specify
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that an object instance having this syntax is to be
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modified, the new value supplied via the management protocol
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must precisely match the value presently held by the
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instance. If not, the management protocol set operation
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fails with an error of `inconsistentValue'. Otherwise, if
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the current value is the maximum value of 2^31-1 (2147483647
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decimal), then the value held by the instance is wrapped to
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zero; otherwise, the value held by the instance is
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incremented by one. (Note that regardless of whether the
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management protocol set operation succeeds, the variable-
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binding in the request and response PDUs are identical.)
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The value of the ACCESS clause for objects having this
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syntax is either `read-write' or `read-create'. When an
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instance of a columnar object having this syntax is created,
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any value may be supplied via the management protocol.
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When the network management portion of the system is re-
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initialized, the value of every object instance having this
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syntax must either be incremented from its value prior to
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the re-initialization, or (if the value prior to the re-
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initialization is unknown) be set to a pseudo-randomly
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generated value."
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SYNTAX INTEGER (0..2147483647)
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AutonomousType ::= TEXTUAL-CONVENTION
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STATUS current
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DESCRIPTION
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"Represents an independently extensible type identification
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value. It may, for example, indicate a particular sub-tree
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with further MIB definitions, or define a particular type of
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protocol or hardware."
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SYNTAX OBJECT IDENTIFIER
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InstancePointer ::= TEXTUAL-CONVENTION
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STATUS obsolete
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DESCRIPTION
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"A pointer to either a specific instance of a MIB object or
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a conceptual row of a MIB table in the managed device. In
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the latter case, by convention, it is the name of the
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particular instance of the first accessible columnar object
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in the conceptual row.
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The two uses of this textual convention are replaced by
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VariablePointer and RowPointer, respectively."
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SYNTAX OBJECT IDENTIFIER
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VariablePointer ::= TEXTUAL-CONVENTION
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STATUS current
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DESCRIPTION
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"A pointer to a specific object instance. For example,
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sysContact.0 or ifInOctets.3."
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SYNTAX OBJECT IDENTIFIER
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RowPointer ::= TEXTUAL-CONVENTION
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STATUS current
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DESCRIPTION
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"Represents a pointer to a conceptual row. The value is the
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name of the instance of the first accessible columnar object
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in the conceptual row.
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For example, ifIndex.3 would point to the 3rd row in the
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ifTable (note that if ifIndex were not-accessible, then
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ifDescr.3 would be used instead)."
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SYNTAX OBJECT IDENTIFIER
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RowStatus ::= TEXTUAL-CONVENTION
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STATUS current
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DESCRIPTION
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"The RowStatus textual convention is used to manage the
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creation and deletion of conceptual rows, and is used as the
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value of the SYNTAX clause for the status column of a
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conceptual row (as described in Section 7.7.1 of [2].)
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McCloghrie, et al. Standards Track [Page 6]
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RFC 2579 Textual Conventions for SMIv2 April 1999
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The status column has six defined values:
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- `active', which indicates that the conceptual row is
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available for use by the managed device;
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- `notInService', which indicates that the conceptual
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row exists in the agent, but is unavailable for use by
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the managed device (see NOTE below); 'notInService' has
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no implication regarding the internal consistency of
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the row, availability of resources, or consistency with
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the current state of the managed device;
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- `notReady', which indicates that the conceptual row
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exists in the agent, but is missing information
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necessary in order to be available for use by the
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managed device (i.e., one or more required columns in
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the conceptual row have not been instanciated);
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- `createAndGo', which is supplied by a management
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station wishing to create a new instance of a
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conceptual row and to have its status automatically set
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to active, making it available for use by the managed
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device;
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- `createAndWait', which is supplied by a management
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station wishing to create a new instance of a
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conceptual row (but not make it available for use by
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the managed device); and,
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- `destroy', which is supplied by a management station
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wishing to delete all of the instances associated with
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an existing conceptual row.
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Whereas five of the six values (all except `notReady') may
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be specified in a management protocol set operation, only
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three values will be returned in response to a management
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protocol retrieval operation: `notReady', `notInService' or
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`active'. That is, when queried, an existing conceptual row
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has only three states: it is either available for use by
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the managed device (the status column has value `active');
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it is not available for use by the managed device, though
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the agent has sufficient information to attempt to make it
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so (the status column has value `notInService'); or, it is
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not available for use by the managed device, and an attempt
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to make it so would fail because the agent has insufficient
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information (the state column has value `notReady').
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McCloghrie, et al. Standards Track [Page 7]
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RFC 2579 Textual Conventions for SMIv2 April 1999
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NOTE WELL
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This textual convention may be used for a MIB table,
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irrespective of whether the values of that table's
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conceptual rows are able to be modified while it is
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active, or whether its conceptual rows must be taken
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out of service in order to be modified. That is, it is
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the responsibility of the DESCRIPTION clause of the
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status column to specify whether the status column must
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not be `active' in order for the value of some other
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column of the same conceptual row to be modified. If
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such a specification is made, affected columns may be
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changed by an SNMP set PDU if the RowStatus would not
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be equal to `active' either immediately before or after
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processing the PDU. In other words, if the PDU also
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contained a varbind that would change the RowStatus
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value, the column in question may be changed if the
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RowStatus was not equal to `active' as the PDU was
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received, or if the varbind sets the status to a value
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other than 'active'.
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Also note that whenever any elements of a row exist, the
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RowStatus column must also exist.
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McCloghrie, et al. Standards Track [Page 8]
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RFC 2579 Textual Conventions for SMIv2 April 1999
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To summarize the effect of having a conceptual row with a
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status column having a SYNTAX clause value of RowStatus,
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consider the following state diagram:
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STATE
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+--------------+-----------+-------------+-------------
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| A | B | C | D
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| |status col.|status column|
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|status column | is | is |status column
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ACTION |does not exist| notReady | notInService| is active
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--------------+--------------+-----------+-------------+-------------
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set status |noError ->D|inconsist- |inconsistent-|inconsistent-
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column to | or | entValue| Value| Value
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createAndGo |inconsistent- | | |
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| Value| | |
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--------------+--------------+-----------+-------------+-------------
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set status |noError see 1|inconsist- |inconsistent-|inconsistent-
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column to | or | entValue| Value| Value
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createAndWait |wrongValue | | |
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--------------+--------------+-----------+-------------+-------------
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set status |inconsistent- |inconsist- |noError |noError
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column to | Value| entValue| |
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active | | | |
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| | or | |
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| |see 2 ->D|see 8 ->D| ->D
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--------------+--------------+-----------+-------------+-------------
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set status |inconsistent- |inconsist- |noError |noError ->C
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column to | Value| entValue| |
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notInService | | | |
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| | or | | or
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| |see 3 ->C| ->C|see 6
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--------------+--------------+-----------+-------------+-------------
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set status |noError |noError |noError |noError ->A
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column to | | | | or
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destroy | ->A| ->A| ->A|see 7
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--------------+--------------+-----------+-------------+-------------
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set any other |see 4 |noError |noError |see 5
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column to some| | | |
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value | | see 1| ->C| ->D
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--------------+--------------+-----------+-------------+-------------
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(1) goto B or C, depending on information available to the
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agent.
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(2) if other variable bindings included in the same PDU,
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McCloghrie, et al. Standards Track [Page 9]
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RFC 2579 Textual Conventions for SMIv2 April 1999
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provide values for all columns which are missing but
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required, and all columns have acceptable values, then
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return noError and goto D.
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(3) if other variable bindings included in the same PDU,
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provide legal values for all columns which are missing but
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required, then return noError and goto C.
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(4) at the discretion of the agent, the return value may be
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either:
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inconsistentName: because the agent does not choose to
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create such an instance when the corresponding
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RowStatus instance does not exist, or
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inconsistentValue: if the supplied value is
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inconsistent with the state of some other MIB object's
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value, or
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noError: because the agent chooses to create the
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instance.
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If noError is returned, then the instance of the status
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column must also be created, and the new state is B or C,
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depending on the information available to the agent. If
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inconsistentName or inconsistentValue is returned, the row
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remains in state A.
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(5) depending on the MIB definition for the column/table,
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either noError or inconsistentValue may be returned.
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(6) the return value can indicate one of the following
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errors:
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wrongValue: because the agent does not support
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notInService (e.g., an agent which does not support
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createAndWait), or
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inconsistentValue: because the agent is unable to take
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the row out of service at this time, perhaps because it
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is in use and cannot be de-activated.
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(7) the return value can indicate the following error:
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inconsistentValue: because the agent is unable to
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remove the row at this time, perhaps because it is in
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use and cannot be de-activated.
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McCloghrie, et al. Standards Track [Page 10]
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RFC 2579 Textual Conventions for SMIv2 April 1999
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(8) the transition to D can fail, e.g., if the values of the
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conceptual row are inconsistent, then the error code would
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be inconsistentValue.
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NOTE: Other processing of (this and other varbinds of) the
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set request may result in a response other than noError
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being returned, e.g., wrongValue, noCreation, etc.
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Conceptual Row Creation
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There are four potential interactions when creating a
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conceptual row: selecting an instance-identifier which is
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not in use; creating the conceptual row; initializing any
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objects for which the agent does not supply a default; and,
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making the conceptual row available for use by the managed
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device.
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Interaction 1: Selecting an Instance-Identifier
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The algorithm used to select an instance-identifier varies
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for each conceptual row. In some cases, the instance-
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identifier is semantically significant, e.g., the
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destination address of a route, and a management station
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selects the instance-identifier according to the semantics.
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In other cases, the instance-identifier is used solely to
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distinguish conceptual rows, and a management station
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without specific knowledge of the conceptual row might
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examine the instances present in order to determine an
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unused instance-identifier. (This approach may be used, but
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it is often highly sub-optimal; however, it is also a
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questionable practice for a naive management station to
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attempt conceptual row creation.)
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Alternately, the MIB module which defines the conceptual row
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might provide one or more objects which provide assistance
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in determining an unused instance-identifier. For example,
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|||
|
if the conceptual row is indexed by an integer-value, then
|
|||
|
an object having an integer-valued SYNTAX clause might be
|
|||
|
defined for such a purpose, allowing a management station to
|
|||
|
issue a management protocol retrieval operation. In order
|
|||
|
to avoid unnecessary collisions between competing management
|
|||
|
stations, `adjacent' retrievals of this object should be
|
|||
|
different.
|
|||
|
|
|||
|
Finally, the management station could select a pseudo-random
|
|||
|
number to use as the index. In the event that this index
|
|||
|
|
|||
|
|
|||
|
McCloghrie, et al. Standards Track [Page 11]
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
RFC 2579 Textual Conventions for SMIv2 April 1999
|
|||
|
|
|||
|
|
|||
|
was already in use and an inconsistentValue was returned in
|
|||
|
response to the management protocol set operation, the
|
|||
|
management station should simply select a new pseudo-random
|
|||
|
number and retry the operation.
|
|||
|
|
|||
|
A MIB designer should choose between the two latter
|
|||
|
algorithms based on the size of the table (and therefore the
|
|||
|
efficiency of each algorithm). For tables in which a large
|
|||
|
number of entries are expected, it is recommended that a MIB
|
|||
|
object be defined that returns an acceptable index for
|
|||
|
creation. For tables with small numbers of entries, it is
|
|||
|
recommended that the latter pseudo-random index mechanism be
|
|||
|
used.
|
|||
|
|
|||
|
Interaction 2: Creating the Conceptual Row
|
|||
|
|
|||
|
Once an unused instance-identifier has been selected, the
|
|||
|
management station determines if it wishes to create and
|
|||
|
activate the conceptual row in one transaction or in a
|
|||
|
negotiated set of interactions.
|
|||
|
|
|||
|
Interaction 2a: Creating and Activating the Conceptual Row
|
|||
|
|
|||
|
The management station must first determine the column
|
|||
|
requirements, i.e., it must determine those columns for
|
|||
|
which it must or must not provide values. Depending on the
|
|||
|
complexity of the table and the management station's
|
|||
|
knowledge of the agent's capabilities, this determination
|
|||
|
can be made locally by the management station. Alternately,
|
|||
|
the management station issues a management protocol get
|
|||
|
operation to examine all columns in the conceptual row that
|
|||
|
it wishes to create. In response, for each column, there
|
|||
|
are three possible outcomes:
|
|||
|
|
|||
|
- a value is returned, indicating that some other
|
|||
|
management station has already created this conceptual
|
|||
|
row. We return to interaction 1.
|
|||
|
|
|||
|
- the exception `noSuchInstance' is returned,
|
|||
|
indicating that the agent implements the object-type
|
|||
|
associated with this column, and that this column in at
|
|||
|
least one conceptual row would be accessible in the MIB
|
|||
|
view used by the retrieval were it to exist. For those
|
|||
|
columns to which the agent provides read-create access,
|
|||
|
the `noSuchInstance' exception tells the management
|
|||
|
station that it should supply a value for this column
|
|||
|
when the conceptual row is to be created.
|
|||
|
|
|||
|
|
|||
|
|
|||
|
McCloghrie, et al. Standards Track [Page 12]
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
RFC 2579 Textual Conventions for SMIv2 April 1999
|
|||
|
|
|||
|
|
|||
|
- the exception `noSuchObject' is returned, indicating
|
|||
|
that the agent does not implement the object-type
|
|||
|
associated with this column or that there is no
|
|||
|
conceptual row for which this column would be
|
|||
|
accessible in the MIB view used by the retrieval. As
|
|||
|
such, the management station can not issue any
|
|||
|
management protocol set operations to create an
|
|||
|
instance of this column.
|
|||
|
|
|||
|
Once the column requirements have been determined, a
|
|||
|
management protocol set operation is accordingly issued.
|
|||
|
This operation also sets the new instance of the status
|
|||
|
column to `createAndGo'.
|
|||
|
|
|||
|
When the agent processes the set operation, it verifies that
|
|||
|
it has sufficient information to make the conceptual row
|
|||
|
available for use by the managed device. The information
|
|||
|
available to the agent is provided by two sources: the
|
|||
|
management protocol set operation which creates the
|
|||
|
conceptual row, and, implementation-specific defaults
|
|||
|
supplied by the agent (note that an agent must provide
|
|||
|
implementation-specific defaults for at least those objects
|
|||
|
which it implements as read-only). If there is sufficient
|
|||
|
information available, then the conceptual row is created, a
|
|||
|
`noError' response is returned, the status column is set to
|
|||
|
`active', and no further interactions are necessary (i.e.,
|
|||
|
interactions 3 and 4 are skipped). If there is insufficient
|
|||
|
information, then the conceptual row is not created, and the
|
|||
|
set operation fails with an error of `inconsistentValue'.
|
|||
|
On this error, the management station can issue a management
|
|||
|
protocol retrieval operation to determine if this was
|
|||
|
because it failed to specify a value for a required column,
|
|||
|
or, because the selected instance of the status column
|
|||
|
already existed. In the latter case, we return to
|
|||
|
interaction 1. In the former case, the management station
|
|||
|
can re-issue the set operation with the additional
|
|||
|
information, or begin interaction 2 again using
|
|||
|
`createAndWait' in order to negotiate creation of the
|
|||
|
conceptual row.
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
McCloghrie, et al. Standards Track [Page 13]
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
RFC 2579 Textual Conventions for SMIv2 April 1999
|
|||
|
|
|||
|
|
|||
|
NOTE WELL
|
|||
|
|
|||
|
Regardless of the method used to determine the column
|
|||
|
requirements, it is possible that the management
|
|||
|
station might deem a column necessary when, in fact,
|
|||
|
the agent will not allow that particular columnar
|
|||
|
instance to be created or written. In this case, the
|
|||
|
management protocol set operation will fail with an
|
|||
|
error such as `noCreation' or `notWritable'. In this
|
|||
|
case, the management station decides whether it needs
|
|||
|
to be able to set a value for that particular columnar
|
|||
|
instance. If not, the management station re-issues the
|
|||
|
management protocol set operation, but without setting
|
|||
|
a value for that particular columnar instance;
|
|||
|
otherwise, the management station aborts the row
|
|||
|
creation algorithm.
|
|||
|
|
|||
|
Interaction 2b: Negotiating the Creation of the Conceptual
|
|||
|
Row
|
|||
|
|
|||
|
The management station issues a management protocol set
|
|||
|
operation which sets the desired instance of the status
|
|||
|
column to `createAndWait'. If the agent is unwilling to
|
|||
|
process a request of this sort, the set operation fails with
|
|||
|
an error of `wrongValue'. (As a consequence, such an agent
|
|||
|
must be prepared to accept a single management protocol set
|
|||
|
operation, i.e., interaction 2a above, containing all of the
|
|||
|
columns indicated by its column requirements.) Otherwise,
|
|||
|
the conceptual row is created, a `noError' response is
|
|||
|
returned, and the status column is immediately set to either
|
|||
|
`notInService' or `notReady', depending on whether it has
|
|||
|
sufficient information to (attempt to) make the conceptual
|
|||
|
row available for use by the managed device. If there is
|
|||
|
sufficient information available, then the status column is
|
|||
|
set to `notInService'; otherwise, if there is insufficient
|
|||
|
information, then the status column is set to `notReady'.
|
|||
|
Regardless, we proceed to interaction 3.
|
|||
|
|
|||
|
Interaction 3: Initializing non-defaulted Objects
|
|||
|
|
|||
|
The management station must now determine the column
|
|||
|
requirements. It issues a management protocol get operation
|
|||
|
to examine all columns in the created conceptual row. In
|
|||
|
the response, for each column, there are three possible
|
|||
|
outcomes:
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
McCloghrie, et al. Standards Track [Page 14]
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
RFC 2579 Textual Conventions for SMIv2 April 1999
|
|||
|
|
|||
|
|
|||
|
- a value is returned, indicating that the agent
|
|||
|
implements the object-type associated with this column
|
|||
|
and had sufficient information to provide a value. For
|
|||
|
those columns to which the agent provides read-create
|
|||
|
access (and for which the agent allows their values to
|
|||
|
be changed after their creation), a value return tells
|
|||
|
the management station that it may issue additional
|
|||
|
management protocol set operations, if it desires, in
|
|||
|
order to change the value associated with this column.
|
|||
|
|
|||
|
- the exception `noSuchInstance' is returned,
|
|||
|
indicating that the agent implements the object-type
|
|||
|
associated with this column, and that this column in at
|
|||
|
least one conceptual row would be accessible in the MIB
|
|||
|
view used by the retrieval were it to exist. However,
|
|||
|
the agent does not have sufficient information to
|
|||
|
provide a value, and until a value is provided, the
|
|||
|
conceptual row may not be made available for use by the
|
|||
|
managed device. For those columns to which the agent
|
|||
|
provides read-create access, the `noSuchInstance'
|
|||
|
exception tells the management station that it must
|
|||
|
issue additional management protocol set operations, in
|
|||
|
order to provide a value associated with this column.
|
|||
|
|
|||
|
- the exception `noSuchObject' is returned, indicating
|
|||
|
that the agent does not implement the object-type
|
|||
|
associated with this column or that there is no
|
|||
|
conceptual row for which this column would be
|
|||
|
accessible in the MIB view used by the retrieval. As
|
|||
|
such, the management station can not issue any
|
|||
|
management protocol set operations to create an
|
|||
|
instance of this column.
|
|||
|
|
|||
|
If the value associated with the status column is
|
|||
|
`notReady', then the management station must first deal with
|
|||
|
all `noSuchInstance' columns, if any. Having done so, the
|
|||
|
value of the status column becomes `notInService', and we
|
|||
|
proceed to interaction 4.
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
McCloghrie, et al. Standards Track [Page 15]
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
RFC 2579 Textual Conventions for SMIv2 April 1999
|
|||
|
|
|||
|
|
|||
|
Interaction 4: Making the Conceptual Row Available
|
|||
|
|
|||
|
Once the management station is satisfied with the values
|
|||
|
associated with the columns of the conceptual row, it issues
|
|||
|
a management protocol set operation to set the status column
|
|||
|
to `active'. If the agent has sufficient information to
|
|||
|
make the conceptual row available for use by the managed
|
|||
|
device, the management protocol set operation succeeds (a
|
|||
|
`noError' response is returned). Otherwise, the management
|
|||
|
protocol set operation fails with an error of
|
|||
|
`inconsistentValue'.
|
|||
|
|
|||
|
NOTE WELL
|
|||
|
|
|||
|
A conceptual row having a status column with value
|
|||
|
`notInService' or `notReady' is unavailable to the
|
|||
|
managed device. As such, it is possible for the
|
|||
|
managed device to create its own instances during the
|
|||
|
time between the management protocol set operation
|
|||
|
which sets the status column to `createAndWait' and the
|
|||
|
management protocol set operation which sets the status
|
|||
|
column to `active'. In this case, when the management
|
|||
|
protocol set operation is issued to set the status
|
|||
|
column to `active', the values held in the agent
|
|||
|
supersede those used by the managed device.
|
|||
|
|
|||
|
If the management station is prevented from setting the
|
|||
|
status column to `active' (e.g., due to management station
|
|||
|
or network failure) the conceptual row will be left in the
|
|||
|
`notInService' or `notReady' state, consuming resources
|
|||
|
indefinitely. The agent must detect conceptual rows that
|
|||
|
have been in either state for an abnormally long period of
|
|||
|
time and remove them. It is the responsibility of the
|
|||
|
DESCRIPTION clause of the status column to indicate what an
|
|||
|
abnormally long period of time would be. This period of
|
|||
|
time should be long enough to allow for human response time
|
|||
|
(including `think time') between the creation of the
|
|||
|
conceptual row and the setting of the status to `active'.
|
|||
|
In the absence of such information in the DESCRIPTION
|
|||
|
clause, it is suggested that this period be approximately 5
|
|||
|
minutes in length. This removal action applies not only to
|
|||
|
newly-created rows, but also to previously active rows which
|
|||
|
are set to, and left in, the notInService state for a
|
|||
|
prolonged period exceeding that which is considered normal
|
|||
|
for such a conceptual row.
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
McCloghrie, et al. Standards Track [Page 16]
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
RFC 2579 Textual Conventions for SMIv2 April 1999
|
|||
|
|
|||
|
|
|||
|
Conceptual Row Suspension
|
|||
|
|
|||
|
When a conceptual row is `active', the management station
|
|||
|
may issue a management protocol set operation which sets the
|
|||
|
instance of the status column to `notInService'. If the
|
|||
|
agent is unwilling to do so, the set operation fails with an
|
|||
|
error of `wrongValue' or `inconsistentValue'. Otherwise,
|
|||
|
the conceptual row is taken out of service, and a `noError'
|
|||
|
response is returned. It is the responsibility of the
|
|||
|
DESCRIPTION clause of the status column to indicate under
|
|||
|
what circumstances the status column should be taken out of
|
|||
|
service (e.g., in order for the value of some other column
|
|||
|
of the same conceptual row to be modified).
|
|||
|
|
|||
|
|
|||
|
Conceptual Row Deletion
|
|||
|
|
|||
|
For deletion of conceptual rows, a management protocol set
|
|||
|
operation is issued which sets the instance of the status
|
|||
|
column to `destroy'. This request may be made regardless of
|
|||
|
the current value of the status column (e.g., it is possible
|
|||
|
to delete conceptual rows which are either `notReady',
|
|||
|
`notInService' or `active'.) If the operation succeeds,
|
|||
|
then all instances associated with the conceptual row are
|
|||
|
immediately removed."
|
|||
|
SYNTAX INTEGER {
|
|||
|
-- the following two values are states:
|
|||
|
-- these values may be read or written
|
|||
|
active(1),
|
|||
|
notInService(2),
|
|||
|
|
|||
|
-- the following value is a state:
|
|||
|
-- this value may be read, but not written
|
|||
|
notReady(3),
|
|||
|
|
|||
|
-- the following three values are
|
|||
|
-- actions: these values may be written,
|
|||
|
-- but are never read
|
|||
|
createAndGo(4),
|
|||
|
createAndWait(5),
|
|||
|
destroy(6)
|
|||
|
}
|
|||
|
|
|||
|
TimeStamp ::= TEXTUAL-CONVENTION
|
|||
|
STATUS current
|
|||
|
DESCRIPTION
|
|||
|
"The value of the sysUpTime object at which a specific
|
|||
|
occurrence happened. The specific occurrence must be
|
|||
|
|
|||
|
|
|||
|
McCloghrie, et al. Standards Track [Page 17]
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
RFC 2579 Textual Conventions for SMIv2 April 1999
|
|||
|
|
|||
|
|
|||
|
defined in the description of any object defined using this
|
|||
|
type.
|
|||
|
|
|||
|
If sysUpTime is reset to zero as a result of a re-
|
|||
|
initialization of the network management (sub)system, then
|
|||
|
the values of all TimeStamp objects are also reset.
|
|||
|
However, after approximately 497 days without a re-
|
|||
|
initialization, the sysUpTime object will reach 2^^32-1 and
|
|||
|
then increment around to zero; in this case, existing values
|
|||
|
of TimeStamp objects do not change. This can lead to
|
|||
|
ambiguities in the value of TimeStamp objects."
|
|||
|
SYNTAX TimeTicks
|
|||
|
|
|||
|
|
|||
|
TimeInterval ::= TEXTUAL-CONVENTION
|
|||
|
STATUS current
|
|||
|
DESCRIPTION
|
|||
|
"A period of time, measured in units of 0.01 seconds."
|
|||
|
SYNTAX INTEGER (0..2147483647)
|
|||
|
|
|||
|
DateAndTime ::= TEXTUAL-CONVENTION
|
|||
|
DISPLAY-HINT "2d-1d-1d,1d:1d:1d.1d,1a1d:1d"
|
|||
|
STATUS current
|
|||
|
DESCRIPTION
|
|||
|
"A date-time specification.
|
|||
|
|
|||
|
field octets contents range
|
|||
|
----- ------ -------- -----
|
|||
|
1 1-2 year* 0..65536
|
|||
|
2 3 month 1..12
|
|||
|
3 4 day 1..31
|
|||
|
4 5 hour 0..23
|
|||
|
5 6 minutes 0..59
|
|||
|
6 7 seconds 0..60
|
|||
|
(use 60 for leap-second)
|
|||
|
7 8 deci-seconds 0..9
|
|||
|
8 9 direction from UTC '+' / '-'
|
|||
|
9 10 hours from UTC* 0..13
|
|||
|
10 11 minutes from UTC 0..59
|
|||
|
|
|||
|
* Notes:
|
|||
|
- the value of year is in network-byte order
|
|||
|
- daylight saving time in New Zealand is +13
|
|||
|
|
|||
|
For example, Tuesday May 26, 1992 at 1:30:15 PM EDT would be
|
|||
|
displayed as:
|
|||
|
|
|||
|
1992-5-26,13:30:15.0,-4:0
|
|||
|
|
|||
|
|
|||
|
McCloghrie, et al. Standards Track [Page 18]
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
RFC 2579 Textual Conventions for SMIv2 April 1999
|
|||
|
|
|||
|
|
|||
|
Note that if only local time is known, then timezone
|
|||
|
information (fields 8-10) is not present."
|
|||
|
SYNTAX OCTET STRING (SIZE (8 | 11))
|
|||
|
|
|||
|
|
|||
|
StorageType ::= TEXTUAL-CONVENTION
|
|||
|
STATUS current
|
|||
|
DESCRIPTION
|
|||
|
"Describes the memory realization of a conceptual row. A
|
|||
|
row which is volatile(2) is lost upon reboot. A row which
|
|||
|
is either nonVolatile(3), permanent(4) or readOnly(5), is
|
|||
|
backed up by stable storage. A row which is permanent(4)
|
|||
|
can be changed but not deleted. A row which is readOnly(5)
|
|||
|
cannot be changed nor deleted.
|
|||
|
|
|||
|
If the value of an object with this syntax is either
|
|||
|
permanent(4) or readOnly(5), it cannot be written.
|
|||
|
Conversely, if the value is either other(1), volatile(2) or
|
|||
|
nonVolatile(3), it cannot be modified to be permanent(4) or
|
|||
|
readOnly(5). (All illegal modifications result in a
|
|||
|
'wrongValue' error.)
|
|||
|
|
|||
|
Every usage of this textual convention is required to
|
|||
|
specify the columnar objects which a permanent(4) row must
|
|||
|
at a minimum allow to be writable."
|
|||
|
SYNTAX INTEGER {
|
|||
|
other(1), -- eh?
|
|||
|
volatile(2), -- e.g., in RAM
|
|||
|
nonVolatile(3), -- e.g., in NVRAM
|
|||
|
permanent(4), -- e.g., partially in ROM
|
|||
|
readOnly(5) -- e.g., completely in ROM
|
|||
|
}
|
|||
|
|
|||
|
|
|||
|
|
|||
|
TDomain ::= TEXTUAL-CONVENTION
|
|||
|
STATUS current
|
|||
|
DESCRIPTION
|
|||
|
"Denotes a kind of transport service.
|
|||
|
|
|||
|
Some possible values, such as snmpUDPDomain, are defined in
|
|||
|
the SNMPv2-TM MIB module. Other possible values are defined
|
|||
|
in other MIB modules."
|
|||
|
REFERENCE "The SNMPv2-TM MIB module is defined in RFC 1906."
|
|||
|
SYNTAX OBJECT IDENTIFIER
|
|||
|
|
|||
|
|
|||
|
TAddress ::= TEXTUAL-CONVENTION
|
|||
|
STATUS current
|
|||
|
DESCRIPTION
|
|||
|
"Denotes a transport service address.
|
|||
|
|
|||
|
A TAddress value is always interpreted within the context of a
|
|||
|
TDomain value. Thus, each definition of a TDomain value must
|
|||
|
be accompanied by a definition of a textual convention for use
|
|||
|
with that TDomain. Some possible textual conventions, such as
|
|||
|
SnmpUDPAddress for snmpUDPDomain, are defined in the SNMPv2-TM
|
|||
|
MIB module. Other possible textual conventions are defined in
|
|||
|
other MIB modules."
|
|||
|
REFERENCE "The SNMPv2-TM MIB module is defined in RFC 1906."
|
|||
|
SYNTAX OCTET STRING (SIZE (1..255))
|
|||
|
|
|||
|
|
|||
|
END
|
|||
|
|
|||
|
|