1
SNMPv2-TC DEFINITIONS ::= BEGIN
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TimeTicks FROM SNMPv2-SMI;
7
TEXTUAL-CONVENTION MACRO ::=
18
value(VALUE Syntax) -- adapted ASN.1
33
-- a character string as defined in [2]
34
Text ::= value(IA5String)
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Syntax ::= -- Must be one of the following:
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-- a base type (or its refinement), or
40
| "BITS" "{" NamedBits "}"
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NamedBits ::= NamedBit
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| NamedBits "," NamedBit
45
NamedBit ::= identifier "(" number ")" -- number is nonnegative
49
DisplayString ::= TEXTUAL-CONVENTION
53
"Represents textual information taken from the NVT ASCII
55
character set, as defined in pages 4, 10-11 of RFC 854.
57
To summarize RFC 854, the NVT ASCII repertoire specifies:
59
- the use of character codes 0-127 (decimal)
61
- the graphics characters (32-126) are interpreted as
64
- NUL, LF, CR, BEL, BS, HT, VT and FF have the special
65
meanings specified in RFC 854
67
- the other 25 codes have no standard interpretation
69
- 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
74
same column on the next line.
76
- the sequence 'CR x' for any x other than LF or NUL is
77
illegal. (Note that this also means that a string may
78
end with either 'CR LF' or 'CR NUL', but not with CR.)
80
Any object defined using this syntax may not exceed 255
81
characters in length."
82
SYNTAX OCTET STRING (SIZE (0..255))
84
PhysAddress ::= TEXTUAL-CONVENTION
88
"Represents media- or physical-level addresses."
91
MacAddress ::= TEXTUAL-CONVENTION
95
"Represents an 802 MAC address represented in the
96
`canonical' order defined by IEEE 802.1a, i.e., as if it
97
were transmitted least significant bit first, even though
98
802.5 (in contrast to other 802.x protocols) requires MAC
99
addresses to be transmitted most significant bit first."
100
SYNTAX OCTET STRING (SIZE (6))
102
TruthValue ::= TEXTUAL-CONVENTION
105
"Represents a boolean value."
106
SYNTAX INTEGER { true(1), false(2) }
108
TestAndIncr ::= TEXTUAL-CONVENTION
111
"Represents integer-valued information used for atomic
112
operations. When the management protocol is used to specify
113
that an object instance having this syntax is to be
114
modified, the new value supplied via the management protocol
115
must precisely match the value presently held by the
116
instance. If not, the management protocol set operation
117
fails with an error of `inconsistentValue'. Otherwise, if
118
the current value is the maximum value of 2^31-1 (2147483647
119
decimal), then the value held by the instance is wrapped to
120
zero; otherwise, the value held by the instance is
121
incremented by one. (Note that regardless of whether the
122
management protocol set operation succeeds, the variable-
123
binding in the request and response PDUs are identical.)
125
The value of the ACCESS clause for objects having this
126
syntax is either `read-write' or `read-create'. When an
127
instance of a columnar object having this syntax is created,
128
any value may be supplied via the management protocol.
130
When the network management portion of the system is re-
131
initialized, the value of every object instance having this
132
syntax must either be incremented from its value prior to
133
the re-initialization, or (if the value prior to the re-
134
initialization is unknown) be set to a pseudo-randomly
136
SYNTAX INTEGER (0..2147483647)
138
AutonomousType ::= TEXTUAL-CONVENTION
141
"Represents an independently extensible type identification
142
value. It may, for example, indicate a particular sub-tree
143
with further MIB definitions, or define a particular type of
144
protocol or hardware."
145
SYNTAX OBJECT IDENTIFIER
147
InstancePointer ::= TEXTUAL-CONVENTION
150
"A pointer to either a specific instance of a MIB object or
151
a conceptual row of a MIB table in the managed device. In
152
the latter case, by convention, it is the name of the
153
particular instance of the first accessible columnar object
154
in the conceptual row.
156
The two uses of this textual convention are replaced by
157
VariablePointer and RowPointer, respectively."
158
SYNTAX OBJECT IDENTIFIER
160
VariablePointer ::= TEXTUAL-CONVENTION
163
"A pointer to a specific object instance. For example,
164
sysContact.0 or ifInOctets.3."
165
SYNTAX OBJECT IDENTIFIER
167
RowPointer ::= TEXTUAL-CONVENTION
170
"Represents a pointer to a conceptual row. The value is the
171
name of the instance of the first accessible columnar object
172
in the conceptual row.
174
For example, ifIndex.3 would point to the 3rd row in the
175
ifTable (note that if ifIndex were not-accessible, then
176
ifDescr.3 would be used instead)."
177
SYNTAX OBJECT IDENTIFIER
179
RowStatus ::= TEXTUAL-CONVENTION
182
"The RowStatus textual convention is used to manage the
183
creation and deletion of conceptual rows, and is used as the
184
value of the SYNTAX clause for the status column of a
185
conceptual row (as described in Section 7.7.1 of [2].)
187
The status column has six defined values:
189
- `active', which indicates that the conceptual row is
190
available for use by the managed device;
192
- `notInService', which indicates that the conceptual
193
row exists in the agent, but is unavailable for use by
194
the managed device (see NOTE below); 'notInService' has
195
no implication regarding the internal consistency of
196
the row, availability of resources, or consistency with
197
the current state of the managed device;
199
- `notReady', which indicates that the conceptual row
200
exists in the agent, but is missing information
201
necessary in order to be available for use by the
202
managed device (i.e., one or more required columns in
203
the conceptual row have not been instanciated);
205
- `createAndGo', which is supplied by a management
206
station wishing to create a new instance of a
207
conceptual row and to have its status automatically set
208
to active, making it available for use by the managed
211
- `createAndWait', which is supplied by a management
212
station wishing to create a new instance of a
213
conceptual row (but not make it available for use by
214
the managed device); and,
215
- `destroy', which is supplied by a management station
216
wishing to delete all of the instances associated with
217
an existing conceptual row.
219
Whereas five of the six values (all except `notReady') may
220
be specified in a management protocol set operation, only
221
three values will be returned in response to a management
222
protocol retrieval operation: `notReady', `notInService' or
223
`active'. That is, when queried, an existing conceptual row
224
has only three states: it is either available for use by
225
the managed device (the status column has value `active');
226
it is not available for use by the managed device, though
227
the agent has sufficient information to attempt to make it
228
so (the status column has value `notInService'); or, it is
229
not available for use by the managed device, and an attempt
230
to make it so would fail because the agent has insufficient
231
information (the state column has value `notReady').
235
This textual convention may be used for a MIB table,
236
irrespective of whether the values of that table's
237
conceptual rows are able to be modified while it is
238
active, or whether its conceptual rows must be taken
239
out of service in order to be modified. That is, it is
240
the responsibility of the DESCRIPTION clause of the
241
status column to specify whether the status column must
242
not be `active' in order for the value of some other
243
column of the same conceptual row to be modified. If
244
such a specification is made, affected columns may be
245
changed by an SNMP set PDU if the RowStatus would not
246
be equal to `active' either immediately before or after
247
processing the PDU. In other words, if the PDU also
248
contained a varbind that would change the RowStatus
249
value, the column in question may be changed if the
250
RowStatus was not equal to `active' as the PDU was
251
received, or if the varbind sets the status to a value
254
Also note that whenever any elements of a row exist, the
255
RowStatus column must also exist.
257
To summarize the effect of having a conceptual row with a
258
status column having a SYNTAX clause value of RowStatus,
259
consider the following state diagram:
262
+--------------+-----------+-------------+-------------
264
| |status col.|status column|
265
|status column | is | is |status column
266
ACTION |does not exist| notReady | notInService| is active
267
--------------+--------------+-----------+-------------+-------------
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set status |noError ->D|inconsist- |inconsistent-|inconsistent-
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column to | or | entValue| Value| Value
270
createAndGo |inconsistent- | | |
272
--------------+--------------+-----------+-------------+-------------
273
set status |noError see 1|inconsist- |inconsistent-|inconsistent-
274
column to | or | entValue| Value| Value
275
createAndWait |wrongValue | | |
276
--------------+--------------+-----------+-------------+-------------
277
set status |inconsistent- |inconsist- |noError |noError
278
column to | Value| entValue| |
282
| |see 2 ->D|see 8 ->D| ->D
283
--------------+--------------+-----------+-------------+-------------
284
set status |inconsistent- |inconsist- |noError |noError ->C
285
column to | Value| entValue| |
289
| |see 3 ->C| ->C|see 6
290
--------------+--------------+-----------+-------------+-------------
291
set status |noError |noError |noError |noError ->A
293
destroy | ->A| ->A| ->A|see 7
294
--------------+--------------+-----------+-------------+-------------
295
set any other |see 4 |noError |noError |see 5
296
column to some| | | |
297
value | | see 1| ->C| ->D
298
--------------+--------------+-----------+-------------+-------------
300
(1) goto B or C, depending on information available to the
303
(2) if other variable bindings included in the same PDU,
304
provide values for all columns which are missing but
305
required, and all columns have acceptable values, then
306
return noError and goto D.
308
(3) if other variable bindings included in the same PDU,
309
provide legal values for all columns which are missing but
310
required, then return noError and goto C.
312
(4) at the discretion of the agent, the return value may be
315
inconsistentName: because the agent does not choose to
316
create such an instance when the corresponding
317
RowStatus instance does not exist, or
319
inconsistentValue: if the supplied value is
320
inconsistent with the state of some other MIB object's
323
noError: because the agent chooses to create the
326
If noError is returned, then the instance of the status
327
column must also be created, and the new state is B or C,
328
depending on the information available to the agent. If
329
inconsistentName or inconsistentValue is returned, the row
332
(5) depending on the MIB definition for the column/table,
333
either noError or inconsistentValue may be returned.
335
(6) the return value can indicate one of the following
338
wrongValue: because the agent does not support
339
notInService (e.g., an agent which does not support
342
inconsistentValue: because the agent is unable to take
343
the row out of service at this time, perhaps because it
344
is in use and cannot be de-activated.
346
(7) the return value can indicate the following error:
348
inconsistentValue: because the agent is unable to
349
remove the row at this time, perhaps because it is in
350
use and cannot be de-activated.
352
(8) the transition to D can fail, e.g., if the values of the
353
conceptual row are inconsistent, then the error code would
354
be inconsistentValue.
356
NOTE: Other processing of (this and other varbinds of) the
357
set request may result in a response other than noError
358
being returned, e.g., wrongValue, noCreation, etc.
360
Conceptual Row Creation
362
There are four potential interactions when creating a
363
conceptual row: selecting an instance-identifier which is
364
not in use; creating the conceptual row; initializing any
365
objects for which the agent does not supply a default; and,
366
making the conceptual row available for use by the managed
369
Interaction 1: Selecting an Instance-Identifier
371
The algorithm used to select an instance-identifier varies
372
for each conceptual row. In some cases, the instance-
373
identifier is semantically significant, e.g., the
374
destination address of a route, and a management station
375
selects the instance-identifier according to the semantics.
377
In other cases, the instance-identifier is used solely to
378
distinguish conceptual rows, and a management station
379
without specific knowledge of the conceptual row might
380
examine the instances present in order to determine an
381
unused instance-identifier. (This approach may be used, but
382
it is often highly sub-optimal; however, it is also a
383
questionable practice for a naive management station to
384
attempt conceptual row creation.)
386
Alternately, the MIB module which defines the conceptual row
387
might provide one or more objects which provide assistance
388
in determining an unused instance-identifier. For example,
389
if the conceptual row is indexed by an integer-value, then
390
an object having an integer-valued SYNTAX clause might be
391
defined for such a purpose, allowing a management station to
392
issue a management protocol retrieval operation. In order
393
to avoid unnecessary collisions between competing management
394
stations, `adjacent' retrievals of this object should be
397
Finally, the management station could select a pseudo-random
398
number to use as the index. In the event that this index
400
was already in use and an inconsistentValue was returned in
401
response to the management protocol set operation, the
402
management station should simply select a new pseudo-random
403
number and retry the operation.
405
A MIB designer should choose between the two latter
406
algorithms based on the size of the table (and therefore the
407
efficiency of each algorithm). For tables in which a large
408
number of entries are expected, it is recommended that a MIB
409
object be defined that returns an acceptable index for
410
creation. For tables with small numbers of entries, it is
411
recommended that the latter pseudo-random index mechanism be
414
Interaction 2: Creating the Conceptual Row
416
Once an unused instance-identifier has been selected, the
417
management station determines if it wishes to create and
418
activate the conceptual row in one transaction or in a
419
negotiated set of interactions.
421
Interaction 2a: Creating and Activating the Conceptual Row
423
The management station must first determine the column
424
requirements, i.e., it must determine those columns for
425
which it must or must not provide values. Depending on the
426
complexity of the table and the management station's
427
knowledge of the agent's capabilities, this determination
428
can be made locally by the management station. Alternately,
429
the management station issues a management protocol get
430
operation to examine all columns in the conceptual row that
431
it wishes to create. In response, for each column, there
432
are three possible outcomes:
434
- a value is returned, indicating that some other
435
management station has already created this conceptual
436
row. We return to interaction 1.
438
- the exception `noSuchInstance' is returned,
439
indicating that the agent implements the object-type
440
associated with this column, and that this column in at
441
least one conceptual row would be accessible in the MIB
442
view used by the retrieval were it to exist. For those
443
columns to which the agent provides read-create access,
444
the `noSuchInstance' exception tells the management
445
station that it should supply a value for this column
446
when the conceptual row is to be created.
448
- the exception `noSuchObject' is returned, indicating
449
that the agent does not implement the object-type
450
associated with this column or that there is no
451
conceptual row for which this column would be
452
accessible in the MIB view used by the retrieval. As
453
such, the management station can not issue any
454
management protocol set operations to create an
455
instance of this column.
457
Once the column requirements have been determined, a
458
management protocol set operation is accordingly issued.
459
This operation also sets the new instance of the status
460
column to `createAndGo'.
462
When the agent processes the set operation, it verifies that
463
it has sufficient information to make the conceptual row
464
available for use by the managed device. The information
465
available to the agent is provided by two sources: the
466
management protocol set operation which creates the
467
conceptual row, and, implementation-specific defaults
468
supplied by the agent (note that an agent must provide
469
implementation-specific defaults for at least those objects
470
which it implements as read-only). If there is sufficient
471
information available, then the conceptual row is created, a
472
`noError' response is returned, the status column is set to
473
`active', and no further interactions are necessary (i.e.,
474
interactions 3 and 4 are skipped). If there is insufficient
475
information, then the conceptual row is not created, and the
476
set operation fails with an error of `inconsistentValue'.
477
On this error, the management station can issue a management
478
protocol retrieval operation to determine if this was
479
because it failed to specify a value for a required column,
480
or, because the selected instance of the status column
481
already existed. In the latter case, we return to
482
interaction 1. In the former case, the management station
483
can re-issue the set operation with the additional
484
information, or begin interaction 2 again using
485
`createAndWait' in order to negotiate creation of the
490
Regardless of the method used to determine the column
491
requirements, it is possible that the management
492
station might deem a column necessary when, in fact,
493
the agent will not allow that particular columnar
494
instance to be created or written. In this case, the
495
management protocol set operation will fail with an
496
error such as `noCreation' or `notWritable'. In this
497
case, the management station decides whether it needs
498
to be able to set a value for that particular columnar
499
instance. If not, the management station re-issues the
500
management protocol set operation, but without setting
501
a value for that particular columnar instance;
502
otherwise, the management station aborts the row
505
Interaction 2b: Negotiating the Creation of the Conceptual
508
The management station issues a management protocol set
509
operation which sets the desired instance of the status
510
column to `createAndWait'. If the agent is unwilling to
511
process a request of this sort, the set operation fails with
512
an error of `wrongValue'. (As a consequence, such an agent
513
must be prepared to accept a single management protocol set
514
operation, i.e., interaction 2a above, containing all of the
515
columns indicated by its column requirements.) Otherwise,
516
the conceptual row is created, a `noError' response is
517
returned, and the status column is immediately set to either
518
`notInService' or `notReady', depending on whether it has
519
sufficient information to (attempt to) make the conceptual
520
row available for use by the managed device. If there is
521
sufficient information available, then the status column is
522
set to `notInService'; otherwise, if there is insufficient
523
information, then the status column is set to `notReady'.
524
Regardless, we proceed to interaction 3.
526
Interaction 3: Initializing non-defaulted Objects
528
The management station must now determine the column
529
requirements. It issues a management protocol get operation
530
to examine all columns in the created conceptual row. In
531
the response, for each column, there are three possible
534
- a value is returned, indicating that the agent
535
implements the object-type associated with this column
536
and had sufficient information to provide a value. For
537
those columns to which the agent provides read-create
538
access (and for which the agent allows their values to
539
be changed after their creation), a value return tells
540
the management station that it may issue additional
541
management protocol set operations, if it desires, in
542
order to change the value associated with this column.
544
- the exception `noSuchInstance' is returned,
545
indicating that the agent implements the object-type
546
associated with this column, and that this column in at
547
least one conceptual row would be accessible in the MIB
548
view used by the retrieval were it to exist. However,
549
the agent does not have sufficient information to
550
provide a value, and until a value is provided, the
551
conceptual row may not be made available for use by the
552
managed device. For those columns to which the agent
553
provides read-create access, the `noSuchInstance'
554
exception tells the management station that it must
555
issue additional management protocol set operations, in
556
order to provide a value associated with this column.
558
- the exception `noSuchObject' is returned, indicating
559
that the agent does not implement the object-type
560
associated with this column or that there is no
561
conceptual row for which this column would be
562
accessible in the MIB view used by the retrieval. As
563
such, the management station can not issue any
564
management protocol set operations to create an
565
instance of this column.
567
If the value associated with the status column is
568
`notReady', then the management station must first deal with
569
all `noSuchInstance' columns, if any. Having done so, the
570
value of the status column becomes `notInService', and we
571
proceed to interaction 4.
573
Interaction 4: Making the Conceptual Row Available
575
Once the management station is satisfied with the values
576
associated with the columns of the conceptual row, it issues
577
a management protocol set operation to set the status column
578
to `active'. If the agent has sufficient information to
579
make the conceptual row available for use by the managed
580
device, the management protocol set operation succeeds (a
581
`noError' response is returned). Otherwise, the management
582
protocol set operation fails with an error of
587
A conceptual row having a status column with value
588
`notInService' or `notReady' is unavailable to the
589
managed device. As such, it is possible for the
590
managed device to create its own instances during the
591
time between the management protocol set operation
592
which sets the status column to `createAndWait' and the
593
management protocol set operation which sets the status
594
column to `active'. In this case, when the management
595
protocol set operation is issued to set the status
596
column to `active', the values held in the agent
597
supersede those used by the managed device.
599
If the management station is prevented from setting the
600
status column to `active' (e.g., due to management station
601
or network failure) the conceptual row will be left in the
602
`notInService' or `notReady' state, consuming resources
603
indefinitely. The agent must detect conceptual rows that
604
have been in either state for an abnormally long period of
605
time and remove them. It is the responsibility of the
606
DESCRIPTION clause of the status column to indicate what an
607
abnormally long period of time would be. This period of
608
time should be long enough to allow for human response time
609
(including `think time') between the creation of the
610
conceptual row and the setting of the status to `active'.
611
In the absence of such information in the DESCRIPTION
612
clause, it is suggested that this period be approximately 5
613
minutes in length. This removal action applies not only to
614
newly-created rows, but also to previously active rows which
615
are set to, and left in, the notInService state for a
616
prolonged period exceeding that which is considered normal
617
for such a conceptual row.
619
Conceptual Row Suspension
621
When a conceptual row is `active', the management station
622
may issue a management protocol set operation which sets the
623
instance of the status column to `notInService'. If the
624
agent is unwilling to do so, the set operation fails with an
625
error of `wrongValue' or `inconsistentValue'. Otherwise,
626
the conceptual row is taken out of service, and a `noError'
627
response is returned. It is the responsibility of the
628
DESCRIPTION clause of the status column to indicate under
629
what circumstances the status column should be taken out of
630
service (e.g., in order for the value of some other column
631
of the same conceptual row to be modified).
633
Conceptual Row Deletion
635
For deletion of conceptual rows, a management protocol set
636
operation is issued which sets the instance of the status
637
column to `destroy'. This request may be made regardless of
638
the current value of the status column (e.g., it is possible
639
to delete conceptual rows which are either `notReady',
640
`notInService' or `active'.) If the operation succeeds,
641
then all instances associated with the conceptual row are
642
immediately removed."
644
-- the following two values are states:
645
-- these values may be read or written
648
-- the following value is a state:
649
-- this value may be read, but not written
651
-- the following three values are
652
-- actions: these values may be written,
653
-- but are never read
659
TimeStamp ::= TEXTUAL-CONVENTION
662
"The value of the sysUpTime object at which a specific
663
occurrence happened. The specific occurrence must be
665
defined in the description of any object defined using this
668
If sysUpTime is reset to zero as a result of a re-
669
initialization of the network management (sub)system, then
670
the values of all TimeStamp objects are also reset.
671
However, after approximately 497 days without a re-
672
initialization, the sysUpTime object will reach 2^^32-1 and
673
then increment around to zero; in this case, existing values
674
of TimeStamp objects do not change. This can lead to
675
ambiguities in the value of TimeStamp objects."
678
TimeInterval ::= TEXTUAL-CONVENTION
681
"A period of time, measured in units of 0.01 seconds."
682
SYNTAX INTEGER (0..2147483647)
684
DateAndTime ::= TEXTUAL-CONVENTION
685
DISPLAY-HINT "2d-1d-1d,1d:1d:1d.1d,1a1d:1d"
688
"A date-time specification.
690
field octets contents range
691
----- ------ -------- -----
698
(use 60 for leap-second)
699
7 8 deci-seconds 0..9
700
8 9 direction from UTC '+' / '-'
701
9 10 hours from UTC* 0..13
702
10 11 minutes from UTC 0..59
705
- the value of year is in network-byte order
706
- daylight saving time in New Zealand is +13
708
For example, Tuesday May 26, 1992 at 1:30:15 PM EDT would be
711
1992-5-26,13:30:15.0,-4:0
713
Note that if only local time is known, then timezone
714
information (fields 8-10) is not present."
715
SYNTAX OCTET STRING (SIZE (8 | 11))
717
StorageType ::= TEXTUAL-CONVENTION
720
"Describes the memory realization of a conceptual row. A
721
row which is volatile(2) is lost upon reboot. A row which
722
is either nonVolatile(3), permanent(4) or readOnly(5), is
723
backed up by stable storage. A row which is permanent(4)
724
can be changed but not deleted. A row which is readOnly(5)
725
cannot be changed nor deleted.
727
If the value of an object with this syntax is either
728
permanent(4) or readOnly(5), it cannot be written.
729
Conversely, if the value is either other(1), volatile(2) or
730
nonVolatile(3), it cannot be modified to be permanent(4) or
731
readOnly(5). (All illegal modifications result in a
734
Every usage of this textual convention is required to
735
specify the columnar objects which a permanent(4) row must
736
at a minimum allow to be writable."
739
volatile(2), -- e.g., in RAM
740
nonVolatile(3), -- e.g., in NVRAM
741
permanent(4), -- e.g., partially in ROM
742
readOnly(5) -- e.g., completely in ROM
745
TDomain ::= TEXTUAL-CONVENTION
748
"Denotes a kind of transport service.
750
Some possible values, such as snmpUDPDomain, are defined in
751
the SNMPv2-TM MIB module. Other possible values are defined
752
in other MIB modules."
753
REFERENCE "The SNMPv2-TM MIB module is defined in RFC 1906."
754
SYNTAX OBJECT IDENTIFIER
756
TAddress ::= TEXTUAL-CONVENTION
759
"Denotes a transport service address.
761
A TAddress value is always interpreted within the context of a
762
TDomain value. Thus, each definition of a TDomain value must
763
be accompanied by a definition of a textual convention for use
764
with that TDomain. Some possible textual conventions, such as
765
SnmpUDPAddress for snmpUDPDomain, are defined in the SNMPv2-TM
766
MIB module. Other possible textual conventions are defined in
768
REFERENCE "The SNMPv2-TM MIB module is defined in RFC 1906."
769
SYNTAX OCTET STRING (SIZE (1..255))
added
removed
mibs/SNMPv2-TC.txt
