Sun SNMP Management Agent
Administration Guide for Sun Supported Servers | 
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| C H A P T E R 9 |
The SNMP agent provides traps to send asynchronous updates to management applications. The agent provides notifications for the following:
To configure the agent to send traps to a particular management application, see Chapter 2.
The SNMP variable sunPlatNotificationAdditionalText is now included in the following traps:
In previous versions of the SUN-PLATFORM-MIB, these traps did not include the sunPlatNotificationAdditionalText. The conventional value of this SNMP variable is the NAC name (a formal, slash-delimited path, in ASCII, which describes the entity’s position in the entity tree). Having the NAC name in each of the AttributeChange or StateChange traps helps remote network management systems more directly identify the entity that is causing the trap to be sent.
The information communicated in traps generated by the agent is based on a common set of attributes. For clarity, the sunPlatNotification prefix has been omitted from the following attribute names:
This is an integer uniquely identifying the notification and an indication of the order in which the notifications were generated by the agent.
Note - The agent does not guarantee that its sequencing reflects the order of the underlying events from which the notifications were generated. |
This is a time stamp indicating the time at which the notification was generated.
This attribute is an OID that provides a direct reference to an entry in the MIB representing the resource with which the event is associated.
This attribute is a comma-separated list of ID values that identify the other events to which this event is associated.
This attribute provides an additional OID that further qualifies the purpose of the trap. Not all traps populate this value, and a value of 0.0 identifies that no trap specific value is relevant to the trap.
This attribute provides a further textual description for the trap. The exact content of the string varies depending on the cause of the trap. However, the format used for this string is always of the form:
serial number/hostname/entPhysicalName:trap-specific text |
Where entPhysicalName identifies the physical name of the object raising the trap.
This attribute describes the severity of the cause of the trap. The attribute can take the following values:
This attribute provides a textual description of the probable cause. Examples of the permitted values include:
This attribute provides an additional textual description that supplies further information about the cause of the trap.
This attribute provides a textual description of the potential repair actions. Multiple repair actions might be described, in which case carriage return/line feed (<CR><LF>) sequences are used to delimit individual descriptions of the actions.
This attribute provides the OID of an object whose value changing caused the trap to be sent.
This section describes the function and properties of trap types.
The SNMP agent determines whether an error or warning condition exists against an object based on any sensors related to that object or any subcomponents of that object. For example, a CPU can have an associated fan, and the fan can have an associated tachometer. All three components have an ability to report their operational status. If the tachometer reports that it has a failed operational status, this relates only to the health of the tachometer. Multiple thresholds can be set for all numeric sensors:
The precise semantics of these thresholds depends on the underlying component, and not all components use all the thresholds. When a component uses a threshold, the agent always creates a trap when the threshold is crossed. This means that if the current value reported by the sensor changes dramatically and crosses multiple thresholds at the same time, multiple traps are delivered.
Note - Even if multiple thresholds are crossed in one sample, when the problem is cleared, the resultant traps can occur over a period of time. |
You can determine the threshold values assigned to a numeric sensor by reading the following properties:
These are all 32-bit integer values, the actual numeric threshold being determined by applying the exponent value provided by sunPlatNumericSensorExponent.
For binary sensors, a trap is sent when the value reported by sunPlatBinarySensorCurrent is not the same as that specified by sunPlatBinarySensorExpected. A trap indicating the problem has cleared is sent when sunPlatBinarySensorCurrent returns to the same value as sunPlatBinarySensorExpected.
For any binary sensor, you can determine the precise meanings of the reported values from the descriptions supplied by sunPlatBinarySensorInterpretTrue and sunPlatBinarySensorInterpretFalse.
The sunPlatObjectCreation trap is sent when an object is created within the agent to represent a new component. For example, a new component has been hot-plugged into the system. The agent sends object creation traps only for objects added once it has started, so traps are not generated during the initial phase of discovery when the agent first starts.
The sunPlatObjectDeletion trap is sent when an object is deleted as a result of a component being removed or unconfigured from the system.
Note - The sunPlatNotification prefix has been omitted from the following attribute names for clarity. |
Object creation and deletion traps have the following properties:
This is an integer uniquely identifying the notification and an indication of the order in which the notifications were generated by the agent.
This is a time stamp indicating the time at which the notification was generated.
The attribute is the OID of the entPhysicalDescr column in the entPhysicalTable of the object being created or deleted.
This attribute is the OID of object being created. The OID is that of the entPhysicalDescr object for the row in the entPhysicalTable being created.
The agent can deliver traps whenever a value in an object changes. The type of trap depends on the type of the object:
The sunPlatStateChange trap is sent when a state attribute changes value.
The sunPlatAttributeChangeInteger trap is sent when the value of an integer property changes. This trap is used for all integer property value changes, with the exception of current values with respect to numeric sensors, because such values can change rapidly and can result in a large number of traps.
The sunPlatAttributeChangeString trap is sent when the value of a string property changes. This trap is used for all string property value changes.
The sunPlatAttributeChangeOID trap is sent when the value of an OID property changes. This trap is used for all OID property value changes.
Note - The sunPlatNotification prefix has been omitted from the following attribute names for clarity. |
Depending on the object type causing the trap, different attributes in the trap body are used to supply both before and after values of the changed attribute:
This attribute is used for sunPlatStateChange and sunPlatAttributeChangeInteger traps. The attribute provides the original value of the object identified by sunPlatNotificationChangedOID.
This attribute is used for sunPlatStateChange and sunPlatAttributeChangeInteger traps. The attribute provides the new value of the object identified by sunPlatNotificationChangedOID.
This attribute is used by the sunPlatAttributeChangeString trap. This is the original value of the object identified by sunPlatNotificationChangedOID.
This attribute is used by the sunPlatAttributeChangeString trap. This is the new value of the object identified by sunPlatNotificationChangedOID.
This attribute is used by the sunPlatAttributeChangeOID trap. This is the original value of the object identified by sunPlatNotificationChangedOID.
This attribute is used by the sunPlatAttributeChangeOID trap. This is the new value of the object identified by sunPlatNotificationChangedOID.
The agent sends traps to report potential environmental problems and other warning or error conditions. The definition of an environmental, or other, condition depends on the component. Examples include the speed of a fan dropping below a predetermined threshold and the temperature of a component rising above a threshold.
Sensors, such as numeric sensors, have multiple thresholds defined to reflect warning, critical, and failure conditions. If a sensor value crosses multiple thresholds when sampled, traps are sent for all thresholds that have been crossed. Similarly, when the reading provided by the sensor returns to a value within an acceptable range, traps are sent to indicate that the warning or error condition has cleared.
The traps used by the agent are:
The trap used depends on the nature of the problem as defined by the generic network information model (ITU-T Recommendation M.3100).
Note - The prefix has been omitted from the following attribute names for clarity. |
The attributes supplied by the traps are:
This attribute is set as described in Standard Trap Properties.
This attribute is set as described in Standard Trap Properties.
This attribute is set as described in Standard Trap Properties.
This attribute is assigned an empty string when an alarm is first raised. When the alarm condition is cleared, the value is the string representation of the sunPlatNotificationEventId value that was sent in the trap when the alarm condition was first raised.
This attribute is set as described in Standard Trap Properties.
This attribute is set as described in Standard Trap Properties.
This attribute is set as described in Standard Trap Properties.
This attribute is set as described in Standard Trap Properties.
This attribute is set as described in Standard Trap Properties.
This attribute is set as described in Standard Trap Properties.
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Sun SNMP Management Agent
Administration Guide for Sun Supported Servers | 821-0655-10 |
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Copyright © 2009, Sun Microsystems, Inc. All rights reserved.