Field Name

Syntax

Size (bytes)

Description

PDU Type

Integer (Enumerated)

4

Request ID

Integer

4

Request Identifier: A number used to match requests with replies. It is generated by the device that sends a request and copied into this field in a Response-PDU by the responding SNMP entity.

Error Status

Integer (Enumerated)

4

Error Status: An integer value that is used in a Response-PDU to tell the requesting SNMP entity the result of its request. A value of zero indicates that no error occurred; the other values indicate what sort of error happened.

Note that the first six values (0 to 5) are maintained as used in SNMPv1 for compatibility, but SNMPv2 adds many new error codes that provide more specific indication of the exact nature of an error in a request. The genErr code is still used only when none of specific error types (either the old codes or the new ones) apply.

Since there are so many different Error Status codes, I have listed them separately in Table 219.

Error Index

Integer

4

Error Index: When Error Status is non-zero, this field contains a pointer that specifies which object generated the error. Always zero in a request.

Variable Bindings

Variable

Variable

Variable Bindings: A set of name-value pairs identifying the MIB objects in the PDU, and in the case of messages other than requests, containing their values. See the general message format topic for more on these bindings.

Error Status Value

Error Code

Description

0

noError

No error occurred. This code is also used in all request PDUs, since they have no error status to report.

1

tooBig

The size of the Response-PDU would be too large to transport.

2

noSuchName

The name of a requested object was not found.

3

badValue

A value in the request didn't match the structure that the recipient of the request had for the object. For example, an object in the request was specified with an incorrect length or type.

4

readOnly

An attempt was made to set a variable that has an Access value indicating that it is read-only.

5

genErr

An error occurred other than one indicated by a more specific error code in this table.

6

noAccess

Access was denied to the object for security reasons.

7

wrongType

The object type in a variable binding is incorrect for the object.

8

wrongLength

A variable binding specifies a length incorrect for the object.

9

wrongEncoding

A variable binding specifies an encoding incorrect for the object.

10

wrongValue

The value given in a variable binding is not possible for the object.

11

noCreation

A specified variable does not exist and cannot be created.

12

inconsistentValue

A variable binding specifies a value that could be held by the variable but cannot be assigned to it at this time.

13

resourceUnavailable

An attempt to set a variable required a resource that is not available.

14

commitFailed

An attempt to set a particular variable failed.

15

undoFailed

An attempt to set a particular variable as part of a group of variables failed, and the attempt to then undo the setting of other variables was not successful.

16

authorizationError

A problem occurred in authorization.

17

notWritable

The variable cannot be written or created.

18

inconsistentName

The name in a variable binding specifies a variable that does not exist.