| OID symbolic | OID numeric | Type | Access | Description |
|---|
| sysUpTimeInstance | 1.3.6.1.2.1.1.3.0 | | | |
| expressionMIB | 1.3.6.1.4.1.9.10.22 | | | The MIB module for defining expressions of MIB objects
for network management purposes.
This MIB is an early snapshot of work done by the IETF's
Distributed Management working group. After this snapshot
was taken, the MIB was modified, had new OIDs assigned,
and then published as RFC 2982. |
| expressionMIBObjects | 1.3.6.1.4.1.9.10.22.1 | | | |
| expResource | 1.3.6.1.4.1.9.10.22.1.1 | | | |
| I32 expResourceDeltaMinimum | 1.3.6.1.4.1.9.10.22.1.1.1 | Integer32 | read-write | The minimum expExpressionDeltaInterval this system will
accept. A system may use the larger values of this minimum
to lessen the impact of constantly computing deltas.
The value -1 indicates this system will not accept
deltaValue as a value for expObjectSampleType.
Unless explicitly resource limited, a system's value for
this object should be 1.
Changing this value will not invalidate an existing setting
of expObjectSampleType. |
| U32 expResourceDeltaWildcardInstanceMaximum | 1.3.6.1.4.1.9.10.22.1.1.2 | Unsigned32 | read-write | The maximum number of dynamic instance entries this system
will support for wildcarded delta objects in expressions.
These are the entries that maintain state, one for each
instance of each deltaValue object for each value of an
expression.
A value of 0 indicates no preset limit, that is, the limit
is dynamic based on system operation and resources.
Unless explicitly resource limited, a system's value for
this object should be 0.
Changing this value will not eliminate or inhibit existing
delta wildcard instance objects but will prevent the
creation of more such objects. |
| G32 expResourceDeltaWildcardInstances | 1.3.6.1.4.1.9.10.22.1.1.3 | Gauge32 | read-only | The number of currently active instance entries as
defined for expResourceDeltaWildcardInstanceMaximum. |
| G32 expResourceDeltaWildcardInstancesHigh | 1.3.6.1.4.1.9.10.22.1.1.4 | Gauge32 | read-only | The highest value of expResourceDeltaWildcardInstances
that has occurred since initialization of the management
system. |
| C32 expResourceDeltaWildcardInstanceResourceLacksEx | 1.3.6.1.4.1.9.10.22.1.1.5 | Counter32 | read-only | The number of times this system could not evaluate an
expression because that would have created a value
instance in excess of
expResourceDeltaWildcardInstanceMaximum. |
| expNames | 1.3.6.1.4.1.9.10.22.1.2 | | | |
| TIM expNameLastChange | 1.3.6.1.4.1.9.10.22.1.2.1 | TimeStamp | read-only | The value of sysUpTime the last time an expression was
created or deleted or had its name changed using
expExpressionName. |
| EXP expNameHighestIndex | 1.3.6.1.4.1.9.10.22.1.2.2 | ExpressionIndexOrZero | read-only | The highest value of ExpressionIndex ever assigned on
this system. Preferrably this value is preserved across
system reboots. A managed system that is unable to
store expressions across reboots need not preserve this
value across reboots.
If all expression-creating applications cooperate, they
may use this to avoid reusing an ExpressionIndex. To
do so, attempt creation of a new entry with this
value + 1 as the value of expExpressionIndex.
Although reusing ExpressionIndexes could lead to an
application receiving a misunderstood value, it is a
matter of local management policy whether to reuse them. |
| expNameTable | 1.3.6.1.4.1.9.10.22.1.2.3 | | not-accessible | A table of expression names, for creating and deleting
expressions. |
| expNameEntry | 1.3.6.1.4.1.9.10.22.1.2.3.1 | | not-accessible | Information about a single expression. New expressions
can be created using expNameStatus.
To create an expression first create the named entry in this
table. Then use expExpressionIndex to populate
expExpressionTable and expObjectTable. For expression
evaluation to succeed all related entries in expNameTable,
expExpressionTable, and expObjectTable must be 'active'. If
these conditions are not met the corresponding values in
expValue simply are not instantiated.
Deleting an entry deletes all related entries in
expExpressionTable and expObjectTable.
Because of the relationships among the multiple tables
for an expression (expNameTable, expExpressionTable,
expObjectTable, and expValueTable) and the SNMP rules
for independence in setting object values, it is
necessary to do final error checking when an expression
is evaluated, that is, when one of its instances in
expValueTable is read. Earlier checking need not be
done and an implementation may not impose any ordering
on the creation of objects related to an expression other
than to require values for expName and expExpressionIndex
before any other related objects can be created.
To maintain security of MIB information, when creating a new
row in this table, the managed system must record the
security credentials of the requester. If the subsequent
expression includes objects with expObjectSampleType
'deltaValue' the evaluation of that expression takes place
under the security credentials of the creator of its
expNameEntry. |
| EXP expName | 1.3.6.1.4.1.9.10.22.1.2.3.1.1 | ExpressionName | not-accessible | The name of the expression. Choosing names with useful
lexical ordering supports using GetNext or GetBulk to
retrieve a useful subset of the table. |
| EXP expExpressionIndex | 1.3.6.1.4.1.9.10.22.1.2.3.1.2 | ExpressionIndex | read-create | The numeric identification of the expression.
Applications may select this number in ascending numerical
order by using expNameHighestIndex as a hint or may use any
other acceptable, unused number.
Once set this value may not be set to a different value. |
| ROW expNameStatus | 1.3.6.1.4.1.9.10.22.1.2.3.1.3 | RowStatus | read-create | The control that allows creation/deletion of entries. |
| expDefine | 1.3.6.1.4.1.9.10.22.1.3 | | | |
| expExpressionTable | 1.3.6.1.4.1.9.10.22.1.3.1 | | not-accessible | A table of expression definitions. |
| expExpressionEntry | 1.3.6.1.4.1.9.10.22.1.3.1.1 | | not-accessible | Information about a single expression. An entry appears
in this table when an entry is created in expNameTable.
Deleting that expNameTable entry automatically deletes
this entry and its associated expObjectTable entries.
Values of read-write objects in this table may be changed
at any time. |
| EXP expExpressionName | 1.3.6.1.4.1.9.10.22.1.3.1.1.1 | ExpressionName | read-write | The unique name of the expression, the same as expName.
Use this object to change the expression's name without
changing its expExpressionIndex. |
| OCT expExpression | 1.3.6.1.4.1.9.10.22.1.3.1.1.2 | OCTET STRING | read-write | The expression to be evaluated. This object is the same
as a DisplayString (RFC 1903) except for its maximum length.
Except for the variable names the expression is in ANSI C
syntax. Only the subset of ANSI C operators and functions
listed here is allowed.
Variables are expressed as a dollar sign ('$') and an
integer that corresponds to an expObjectIndex. An
example of a valid expression is:
($1-$5)*100
Expressions may not be recursive, that is although an
expression may use the results of another expression, it
may not contain any variable that is directly or
indirectly a result of its own evaluation.
The only allowed operators are:
( )
- (unary)
+ - * / %
& | ^ > ~
! && || == != > >= > the result is the same as the left hand
operand.
For &&, ||, ==, !=, , and >= the result is always
Unsigned32.
For unary - the result is always Integer32.
For +, -, *, /, %, &, |, and ^ the result is promoted
according to the following rules, in order from most to
least preferred:
If left hand and right hand operands are the same
type, use that.
If either side is Counter64, use that.
If either side is IpAddress, use that.
If either side is TimeTicks, use that.
If either side is Counter32, use that.
Otherwise use Unsigned32.
The following rules say what operators apply with what
data types. Any combination not explicitly defined does
not work.
For all operators any of the following can be the left
hand or right hand operand: Integer32, Counter32,
Unsigned32, Counter64.
The operators +, -, *, /, %, , and >= also work with
TimeTicks.
The operators &, |, and ^ also work with IpAddress.
The operators > also work with IpAddress but only
as the left hand operand.
The + operator performs a concatenation of two OCTET STRINGs
or two OBJECT IDENTIFIERs.
The operators &, | perform bitwise operations on
OCTET STRINGs. If the OCTET STRING happens to be a
DisplayString the results may be meaningless, but the agent
system does not check this as some such systems do not
have this information.
The operators > perform bitwise operations on
OCTET STRINGs appearing as the left hand operand.
The only functions defined are:
counter32
counter64
arraySection
stringBegins
stringEnds
stringContains
oidBegins
oidEnds
oidContains
sum
exists
The following function definitions indicate their by naming
the data type of the parameter in the parameter's position
in the parameter list. The parameter must be of the type
indicated and generally may be a constant, a MIB object, a
function, or an expression.
counter32(integer) - wrapped around an integer value
counter32 forces Counter32 as a data type.
counter64(integer) - similar to counter32 except that the
resulting data type is 'counter64'.
arraySection(array, integer, integer) - selects a piece of
an array (i.e. part of an OCTET STRING or
OBJECT IDENTIFIER). The integer arguments are in the
range 0 to 4,294,967,295. The first is an initial array
index (1-based) and the second is an ending array index.
A value of 0 indicates first or last element, respectively.
If the first element is larger than the array length the
result is 0 length. If the second integer is less than or
equal to the first, the result is 0 length. If the second
is larger than the array length it indicates last element.
stringBegins/Ends/Contains(octetString, octetString) -
looks for the second string (which can be a string constant)
in the first and returns the 1-based index where the match
began. A return value of 0 indicates no match (i.e.
boolean false).
oidBegins/Ends/Contains(oid, oid) - looks for the second OID
(which can be an OID constant) in the first and returns the
the 1-based index where the match began. A return value
of 0 indicates no match (i.e. boolean false).
sum(integerObject*) - sums all availiable values of the
wildcarded integer object, resulting in an integer scalar.
Must be used with caution as it wraps on overflow with no
notification.
exists(anyTypeObject) - verifies the object instance
exists. A return value of 0 indicates NoSuchInstance
(i.e. boolean false). |
| INT expExpressionValueType | 1.3.6.1.4.1.9.10.22.1.3.1.1.3 | INTEGER | read-write | The type of the expression value. One and only one of
the value objects in expValueTable will be instantiated to
match this type.
If the result of the expression can not be made into this
type, an invalidOperandType error will occur. |
| I32 expExpressionDeltaInterval | 1.3.6.1.4.1.9.10.22.1.3.1.1.5 | Integer32 | read-write | Sampling interval for objects in this expression with
expObjectSampleType 'deltaValue'.
This object is not instantiated if not applicable.
A value of 0 indicates no automated sampling. In this case
the delta is the difference from the last time the
expression was evaluated. Note that this is subject to
unpredictable delta times in the face of retries or
multiple managers.
A value greater than zero is the number of seconds between
automated samples.
Until the delta interval has expired once the delta for the
object is effectively not instantiated and evaluating
the expression has results as if the object itself were not
instantiated.
Note that delta values potentially consume large amounts of
system CPU and memory. Delta state and processing must
continue constantly even if the expression is not being
used. That is, the expression is being evaluated every
delta interval, even if no application is reading those
values. For wildcarded objects this can be substantial
overhead.
Note that delta intervals, external expression value
sampling intervals and delta intervals for expressions
within other expressions can have unusual interactions as
they are impossible to synchronize accurately. In general
one interval embedded below another must be enough shorter
that the higher sample sees relatively smooth, predictable
behavior. |
| OID expExpressionPrefix | 1.3.6.1.4.1.9.10.22.1.3.1.1.6 | OBJECT IDENTIFIER | read-only | An object prefix to assist an application in determining
the instance indexing to use in expValueTable, relieving the
application of the need to scan the expObjectTable to
determine such a prefix.
See expObjectTable for information on wildcarded objects.
If the expValueInstance portion of the value OID may
be treated as a scalar (that is, normally, 0) the value of
expExpressionPrefix is zero length, that is, no OID at all.
Otherwise expExpressionPrefix is the value of any wildcarded
instance of expObjectID for the expression. This is
sufficient as the remainder, that is, the instance fragment
relevant to instancing the values must be the same for all
wildcarded objects in the expression. |
| C32 expExpressionErrors | 1.3.6.1.4.1.9.10.22.1.3.1.1.7 | Counter32 | read-only | The number of errors encountered while evaluating this
expression.
Note that an object in the expression not being accessible
is not considered an error. It is a legitimate condition
that causes the corresponding expression value not to be
instantiated. |
| TIM expExpressionErrorTime | 1.3.6.1.4.1.9.10.22.1.3.1.1.8 | TimeStamp | read-only | The value of sysUpTime the last time an error caused a
failure to evaluate this expression.
This object is not instantiated if there have been no
errors. |
| I32 expExpressionErrorIndex | 1.3.6.1.4.1.9.10.22.1.3.1.1.9 | Integer32 | read-only | The 1-based character index into expExpression for where
the error occurred. The value zero indicates irrelevance.
This object is not instantiated if there have been no
errors. |
| INT expExpressionError | 1.3.6.1.4.1.9.10.22.1.3.1.1.10 | INTEGER | read-only | The error that occurred. In the following explanations the
expected timing of the error is in parentheses. 'S' means
the error occurs on a Set request. 'E' means the error
occurs on the attempt to evaluate the expression either
due to Get from expValueTable or in ongoing delta
processing.
invalidSyntax the value sent for expExpression
is not valid Expression MIB
expression syntax (S)
undefinedObjectIndex an object reference ($n) in
expExpression does not have a
matching instance in
expObjectTable (E)
unrecognizedOperator the value sent for expExpression
held an unrecognized operator (S)
unrecognizedFunction the value sent for expExpression
held an unrecognized function
name (S)
invalidOperandType an operand in expExpression is not
the right type for the associated
operator or result (SE)
unmatchedParenthesis the value sent for expExpression
is not correctly parenthesized (S)
tooManyWildcardValues evaluating the expression exceeded
the limit set by expResourceDelta
WildcardInstanceMaximum (E)
recursion through some chain of embedded
expressions the expression invokes
itself (E)
deltaTooShort the delta for the next evaluation
passed before the system could
evaluate the present sample (E)
resourceUnavailable some resource, typically dynamic
memory, was unavailable (SE)
divideByZero an attempt to divide by zero
occurred (E)
For the errors that occur when the attempt is made to set
expExpression Set request fails with the SNMP error code
'wrongValue'. Such failures refer to the most recent failure
to Set expExpression, not to the present value of
expExpression which must be either unset or syntactically
correct.
Errors that occur during evalutaion for a Get* operation
return the SNMP error code 'genErr' except for
'tooManyWildcardValues' and 'resourceUnavailable' which
return the SNMP error code 'resourceUnavailable'.
This object is not instantiated if there have been no
errors. |
| OID expExpressionInstance | 1.3.6.1.4.1.9.10.22.1.3.1.1.11 | OBJECT IDENTIFIER | read-only | The expValueInstance being evaluated when the error
occurred. A zero-length indicates irrelevance.
This object is not instantiated if there have been no
errors. |
| STR expExpressionOwner | 1.3.6.1.4.1.9.10.22.1.3.1.1.12 | DisplayString | read-write | The entity that configured this entry and is therefore
using the resources assigned to it. |
| expObjectTable | 1.3.6.1.4.1.9.10.22.1.3.2 | | not-accessible | A table of object definitions for each expExpression.
Wildcarding instance IDs:
It is legal to omit all or part of the instance portion for
some or all of the objects in an expression. (See the
DESCRIPTION of expObjectID for details. However, note that
if more than one object in the same expression is wildcarded
in this way, they all must be objects where that portion of
the instance is the same. In other words, all objects may
be in the same SEQUENCE or in different SEQUENCEs but with
the same semantic index value (e.g., a value of ifIndex)
for the wildcarded portion. |
| expObjectEntry | 1.3.6.1.4.1.9.10.22.1.3.2.1 | | not-accessible | Information about an object. An application uses
expObjectStatus to create entries in this table while
in the process of defining an expression.
Values of read-create objects in this table may be
changed at any time. |
| U32 expObjectIndex | 1.3.6.1.4.1.9.10.22.1.3.2.1.1 | Unsigned32 | not-accessible | Within an expression, a unique, numeric identification
for an object. Prefixed with a dollar sign ('$') this is
used to reference the object in the corresponding
expExpression. |
| OID expObjectID | 1.3.6.1.4.1.9.10.22.1.3.2.1.2 | OBJECT IDENTIFIER | read-create | The OBJECT IDENTIFIER (OID) of this object. The OID may be
fully qualified, meaning it includes a complete instance
identifier part (e.g., ifInOctets.1 or sysUpTime.0), or it
may not be fully qualified, meaning it may lack all or part
of the instance identifier. If the expObjectID is not fully
qualified, then expObjectWildcard must be set to true(1).
The value of the expression will be multiple
values, as if done for a GetNext sweep of the object.
An object here may itself be the result of an expression but
recursion is not allowed.
NOTE: The simplest implementations of this MIB may not
allow wildcards. |
| T/F expObjectIDWildcard | 1.3.6.1.4.1.9.10.22.1.3.2.1.3 | TruthValue | read-create | A true value indicates the expObjecID of this row is a
wildcard object. False indicates that expObjectID is fully
instanced. If all expObjectWildcard values for a given
expression are FALSE, expExpressionPrefix will reflect a
scalar object (ie will be 0.0).
NOTE: The simplest implementations of this MIB may not
allow wildcards. |
| INT expObjectSampleType | 1.3.6.1.4.1.9.10.22.1.3.2.1.4 | INTEGER | read-create | The method of sampling the selected variable.
An 'absoluteValue' is simply the present value of the
object.
A 'deltaValue' is the present value minus the previous
value, which was sampled expExpressionDeltaInterval
seconds ago. This is intended primarily for use with
SNMP counters, which are meaningless as an 'absoluteValue',
but may be used with any integer-based value.
When an expression contains both delta and absolute values
the absolute values are obtained at the end of the delta
period. |
| OID expObjectDeltaDiscontinuityID | 1.3.6.1.4.1.9.10.22.1.3.2.1.5 | OBJECT IDENTIFIER | read-create | The OBJECT IDENTIFIER (OID) of a TimeTicks or TimeStamp
object that indicates a discontinuity in the value at
expObjectID.
This object is not instantiated if expObject is not
'deltaValue'.
The OID may be for a leaf object (e.g. sysUpTime.0) or may
be wildcarded to match expObjectID.
This object supports normal checking for a discontinuity
in a counter. Note that if this object does not point to
sysUpTime discontinuity checking must still check sysUpTime
for an overall discontinuity.
If the object identified is not accessible no discontinuity
check will be made. |
| T/F expObjectDiscontinuityIDWildcard | 1.3.6.1.4.1.9.10.22.1.3.2.1.6 | TruthValue | read-create | A true value indicates the expObjectDeltaDiscontinuityID
of this row is a wildcard object. False indicates that
expObjectDeltaDiscontinuityID is fully instanced.
This object is not instantiated if expObject is not
'deltaValue'.
NOTE: The simplest implementations of this MIB may not
allow wildcards. |
| INT expObjectDiscontinuityIDType | 1.3.6.1.4.1.9.10.22.1.3.2.1.7 | INTEGER | read-create | The value 'timeTicks' indicates the
expObjectDeltaDiscontinuityID of this row is of syntax
TimeTicks. The value 'timeStamp' indicates that
expObjectDeltaDiscontinuityID is of syntax TimeStamp.
This object is not instantiated if expObject is not
'deltaValue'. |
| OID expObjectConditional | 1.3.6.1.4.1.9.10.22.1.3.2.1.8 | OBJECT IDENTIFIER | read-create | The OBJECT IDENTIFIER (OID) of an object that overrides
whether the instance of expObjectID is to be considered
usable. If the value of the object at expObjectConditional
is 0 or not instantiated, the object at expObjectID is
treated as if it is not instantiated. In other words,
expObjectConditional is a filter that controls whether or
not to use the value at expObjectID.
The OID may be for a leaf object (e.g. sysObjectID.0) or
may be wildcarded to match expObjectID. If expObject is
wildcarded and expObjectID in the same row is not, the wild
portion of expObjectConditional must match the wildcarding
of the rest of the expression. If no object in the
expression is wildcarded but expObjectConditional is, use
the lexically first instance (if any) of
expObjectConditional.
If the value of expObjectConditional is 0.0 operation is
as if the value pointed to by expObjectConditional is a
non-zero (true) value.
Note that expObjectConditional can not trivially use an
object of syntax TruthValue, since the underlying value is
not 0 or 1. |
| T/F expObjectConditionalWildcard | 1.3.6.1.4.1.9.10.22.1.3.2.1.9 | TruthValue | read-create | A true value indicates the expObjectConditional of this
row is a wildcard object. False indicates that
expObjectConditional is fully instanced.
NOTE: The simplest implementations of this MIB may not allow
wildcards. |
| ROW expObjectStatus | 1.3.6.1.4.1.9.10.22.1.3.2.1.10 | RowStatus | read-create | The control that allows creation/deletion of entries.
Objects in this table may be changed while expObjectStatus
is in any state. |
| expValue | 1.3.6.1.4.1.9.10.22.1.4 | | | |
| expValueTable | 1.3.6.1.4.1.9.10.22.1.4.1 | | not-accessible | A table of values from evaluated expressions. |
| expValueEntry | 1.3.6.1.4.1.9.10.22.1.4.1.1 | | not-accessible | A single value from an evaluated expression. For a given
instance, only one 'Val' object in the conceptual row will
be instantiated, that is, the one with the appropriate type
for the value. For values that contain no objects of
expObjectSampleType 'deltaValue', reading a value from the
table causes the evaluation of the expression for that
value. For those that contain a 'deltaValue' the value
read is as of the last delta interval.
If in the attempt to evaluate the expression one or more
of the necessary objects is not available, the corresponding
entry in this table is effectively not instantiated.
To maintain security of MIB information, expression
evaluation must take place using security credentials for
the implied Gets of the objects in the expression. For
expressions with no deltaValue those security credentials
are the ones that came with the Get* for the value. For
expressions with a deltaValue the ongoing expression
evaluation is under the security credentials of the
creator of the corresponding expNameEntry. |
| OID expValueInstance | 1.3.6.1.4.1.9.10.22.1.4.1.1.1 | OBJECT IDENTIFIER | not-accessible | The final instance portion of a value's OID according to
the wildcarding in instances of expObjectID for the
expression. The prefix of this OID fragment is 0.0,
leading to the following behavior.
If there is no wildcarding, the value is 0.0.0. In other
words, there is one value which standing alone would have
been a scalar with a 0 at the end of its OID.
If there is wildcarding, the value is 0.0 followed by
a value that the wildcard can take, thus defining one value
instance for each real, possible value of the wildcard.
So, for example, if the wildcard worked out to be an
ifIndex, there is an expValueInstance for each applicable
ifIndex. |
| C32 expValueCounter32Val | 1.3.6.1.4.1.9.10.22.1.4.1.1.2 | Counter32 | read-only | The value when expExpressionValueType is 'counter32'. |
| U32 expValueUnsigned32Val | 1.3.6.1.4.1.9.10.22.1.4.1.1.3 | Unsigned32 | read-only | The value when expExpressionValueType is
'unsignedOrGauge32' or 'timeTicks'. |
| I32 expValueInteger32Val | 1.3.6.1.4.1.9.10.22.1.4.1.1.4 | Integer32 | read-only | The value when expExpressionValueType is 'integer32'. |
| IP expValueIpAddressVal | 1.3.6.1.4.1.9.10.22.1.4.1.1.5 | IpAddress | read-only | The value when expExpressionValueType is 'ipAddress'. |
| OCT expValueOctetStringVal | 1.3.6.1.4.1.9.10.22.1.4.1.1.6 | OCTET STRING | read-only | The value when expExpressionValueType is 'octetString'. |
| OID expValueOidVal | 1.3.6.1.4.1.9.10.22.1.4.1.1.7 | OBJECT IDENTIFIER | read-only | The value when expExpressionValueType is 'objectId'. |
| C64 expValueCounter64Val | 1.3.6.1.4.1.9.10.22.1.4.1.1.8 | Counter64 | read-only | The value when expExpressionValueType is 'counter64'. |
| expressionMIBConformance | 1.3.6.1.4.1.9.10.22.3 | | | |
| expressionMIBCompliances | 1.3.6.1.4.1.9.10.22.3.1 | | | |
| expressionMIBCompliance | 1.3.6.1.4.1.9.10.22.3.1.1 | | | The compliance statement for entities which implement
the Expression MIB. |
| expressionMIBGroups | 1.3.6.1.4.1.9.10.22.3.2 | | | |
| expressionResourceGroup | 1.3.6.1.4.1.9.10.22.3.2.1 | | | Expression definition resource management. |
| expressionDefinitionGroup | 1.3.6.1.4.1.9.10.22.3.2.2 | | | Expression definition resource management. |
| expressionValueGroup | 1.3.6.1.4.1.9.10.22.3.2.3 | | | Expression definition resource management. |
