All MIBs › ENTITY-SENSOR-MIB
Organization: IETF Entity MIB Working Group
Last Updated: 2002-12-16
Category: Hardware and Environment
Description:
An extension of ENTITY-MIB adding support for physical sensors on networking equipment, so environmental parameters like temperature, voltage, and fan speed can be monitored.
Imported Objects
From ENTITY-MIB
| entPhysicalIndex | OBJECT-TYPE |
| entityPhysicalGroup | OBJECT-GROUP |
From SNMP-FRAMEWORK-MIB
| SnmpAdminString |
From SNMPv2-CONF
| MODULE-COMPLIANCE | |
| OBJECT-GROUP |
From SNMPv2-SMI
| Integer32 | |
| MODULE-IDENTITY | |
| OBJECT-TYPE | |
| Unsigned32 | |
| mib-2 |
From SNMPv2-TC
| TEXTUAL-CONVENTION | |
| TimeStamp |
What Is ENTITY-SENSOR-MIB?
ENTITY-SENSOR-MIB is a vendor-neutral IETF standards-track module (RFC 3433) that extends the ENTITY-MIB to describe physical sensors mounted on networking equipment components. It exposes data on sensor type, measurement scale, precision, current reading, operational status, and the timestamp of the last update, covering environmental parameters like temperature, voltage, current, and fan speed. It is squarely a hardware health monitoring MIB: administrators use it to track whether temperature sensors, power-supply voltage sensors, and fan tachometers are reading normal values or reporting a fault/out-of-range condition on physical entities such as chassis, modules, and power supplies. Because entPhySensorTable entries are indexed against entPhysicalIndex, this MIB has a hard dependency on ENTITY-MIB for entity identification. It is deployed on any router, switch, or chassis-based device that reports physical sensor readings via SNMP, typically polled by NMS platforms for environmental alerting, and engineers researching entity-sensor-mib object definitions will find RFC 3433 the canonical reference for how those readings are structured.
IPNetwork Monitor allows you to monitor SNMP objects defined in ENTITY-SENSOR-MIB. Use the built-in SNMP Monitoring Browser to explore available variables, view their current values and descriptions, and select the objects you want to monitor. You can then create SNMP monitors, configure thresholds, and receive alerts when monitored values change.
What Can Be Monitored
- temperature sensor readings
- voltage sensor readings
- fan speed
- sensor operational status
- sensor value precision/scale
- sensor reading freshness (timestamp/update rate)
Supported Devices
- vendor-neutral, standards-based MIB, not tied to a specific manufacturer
- modular routers and switches
- chassis-based network equipment
Monitoring Examples
An admin polls entPhySensorTable, joining entPhySensorValue (scaled by entPhySensorScale and entPhySensorPrecision) with entPhySensorType to distinguish a temperature sensor from a voltage or fan-speed sensor on a given entPhysicalIndex. A rising entPhySensorValue on a temperature-type sensor combined with entPhySensorOperStatus moving from 'ok' to 'nonoperational' would flag an overheating card or failed fan before a hard failure. entPhySensorValueTimeStamp and entPhySensorValueUpdateRate help the poller confirm the sensor reading is fresh rather than stale.
OIDs
| OID symbolic | OID numeric | Type | Access | Description |
|---|---|---|---|---|
| entitySensorMIB | 1.3.6.1.2.1.99 | This module defines Entity MIB extensions for physical sensors. Copyright (C) The Internet Society (2002). This version of this MIB module is part of RFC 3433; see the RFC itself for full legal notices. | ||
| entitySensorObjects | 1.3.6.1.2.1.99.1 | |||
| entPhySensorTable | 1.3.6.1.2.1.99.1.1 | not-accessible | This table contains one row per physical sensor represented by an associated row in the entPhysicalTable. | |
| entPhySensorEntry | 1.3.6.1.2.1.99.1.1.1 | not-accessible | Information about a particular physical sensor. An entry in this table describes the present reading of a sensor, the measurement units and scale, and sensor operational status. Entries are created in this table by the agent. An entry for each physical sensor SHOULD be created at the same time as the associated entPhysicalEntry. An entry SHOULD be destroyed if the associated entPhysicalEntry is destroyed. | |
| ENT entPhySensorType | 1.3.6.1.2.1.99.1.1.1.1 | EntitySensorDataType | read-only | The type of data returned by the associated entPhySensorValue object. This object SHOULD be set by the agent during entry creation, and the value SHOULD NOT change during operation. |
| ENT entPhySensorScale | 1.3.6.1.2.1.99.1.1.1.2 | EntitySensorDataScale | read-only | The exponent to apply to values returned by the associated entPhySensorValue object. This object SHOULD be set by the agent during entry creation, and the value SHOULD NOT change during operation. |
| ENT entPhySensorPrecision | 1.3.6.1.2.1.99.1.1.1.3 | EntitySensorPrecision | read-only | The number of decimal places of precision in fixed-point sensor values returned by the associated entPhySensorValue object. This object SHOULD be set to '0' when the associated entPhySensorType value is not a fixed-point type: e.g., 'percentRH(9)', 'rpm(10)', 'cmm(11)', or 'truthvalue(12)'. This object SHOULD be set by the agent during entry creation, and the value SHOULD NOT change during operation. |
| ENT entPhySensorValue | 1.3.6.1.2.1.99.1.1.1.4 | EntitySensorValue | read-only | The most recent measurement obtained by the agent for this sensor. To correctly interpret the value of this object, the associated entPhySensorType, entPhySensorScale, and entPhySensorPrecision objects must also be examined. |
| ENT entPhySensorOperStatus | 1.3.6.1.2.1.99.1.1.1.5 | EntitySensorStatus | read-only | The operational status of the sensor. |
| STR entPhySensorUnitsDisplay | 1.3.6.1.2.1.99.1.1.1.6 | SnmpAdminString | read-only | A textual description of the data units that should be used in the display of entPhySensorValue. |
| TIM entPhySensorValueTimeStamp | 1.3.6.1.2.1.99.1.1.1.7 | TimeStamp | read-only | The value of sysUpTime at the time the status and/or value of this sensor was last obtained by the agent. |
| U32 entPhySensorValueUpdateRate | 1.3.6.1.2.1.99.1.1.1.8 | Unsigned32 | read-only | An indication of the frequency that the agent updates the associated entPhySensorValue object, representing in milliseconds. The value zero indicates: - the sensor value is updated on demand (e.g., when polled by the agent for a get-request), - the sensor value is updated when the sensor value changes (event-driven), - the agent does not know the update rate. |
| entitySensorConformance | 1.3.6.1.2.1.99.3 | |||
| entitySensorCompliances | 1.3.6.1.2.1.99.3.1 | |||
| entitySensorCompliance | 1.3.6.1.2.1.99.3.1.1 | Describes the requirements for conformance to the Entity Sensor MIB module. | ||
| entitySensorGroups | 1.3.6.1.2.1.99.3.2 | |||
| entitySensorValueGroup | 1.3.6.1.2.1.99.3.2.1 | A collection of objects representing physical entity sensor information. |
RFC description
Extends ENTITY-MIB with support for physical sensors on networking equipment, enabling monitoring of environmental parameters such as temperature, voltage, and fan speed.
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