Power Supplies Test

The chassis of the Juniper EX Switch is a rigid sheet-metal structure that houses the hardware components. The field-replaceable units (FRUs) in the EX series switches are:

  • Power supply
  • Fan tray
  • Uplink module
  • SFP transceiver
  • SFP+ transceiver
  • XFP transceiver

The power supply in the switches is a hot-removable and hot-insertable field-replaceable unit (FRU) that you can install on the rear panel without powering off the switch or disrupting the switching function. Some of the EX series switches have an internal redundant power supply, making the power supply fully redundant.

Abnormal power fluctuation to the hardware components often lead to the malfunctioning of the Juniper EX Switch which when left unnoticed can prove to be fatal to the availability and overall health. This test intercepts the traps sent by the switch, extracts information related to power supply failures from the traps, and reports the count of these trap messages to the eG manager. This information enables administrators to detect the abnormalities in the power supply if any, understand the nature of these failures, and accordingly decide on the remedial measures.

Target of the test : A Juniper EX Switch

Agent deploying the test : An external agent

Outputs of the test : One set of results for each type of event that occurred on the target Juniper EX Switch.

Configurable parameters for the test
Parameters Description

Test Period

How often should the test be executed


The host for which the test is to be configured.

Source Address

Specify a comma-separated list of IP addresses or address patterns of the hosts from which traps are considered in this test. For example,,192.168.10.*. A leading '*' signifies any number of leading characters, while a trailing '*' signifies any number of trailing characters.

OID Value

By default, this parameter is pre-configured with a comma-separated list of Display name:OID pairs returned by the traps for specific failure events/conditions.

The DisplayName in every pair will appear as descriptors of this test in the monitor interface.

You can, if you so wish, override this default specification by appending more DisplayName:OID pairs to the pre-configured list. This way, you can instruct the test to receive traps for failure conditions that are of interest to you. For example, say you want to capture the traps generated for abnormalities in the power supply to the hardware components on the target Juniper EX Switch. To achieve this, you need to append an entry of the following format: DisplayName:OID-any. Typically, the DisplayName can be any meaningful text string that qualifies the failure condition that is to be captured. Since our example seeks to capture abnormalities in the power supply, let us use 'PowerFailure' as the appropriate DisplayName. The OID that reports power failure on Juniper EX Switch is . Therefore, the entry you need to append to the default list will be: PowerFailure:. Similarly, you can append more entries. However, make sure that the new entries are also comma-separated.


Specifying True against ShowOID will ensure that the detailed diagnosis of this test shows the OID strings along with their corresponding values. If you enter False, then the values alone will appear in the detailed diagnosis page, and not the OIDs. 


By default, this parameter is set to all, indicating that the eG agent considers all the traps received from the specified sourceaddresses. To make sure that the agent considers only specific traps received from the SourceAddress, then provide a comma-separated list of OIDs in the trapoids text box. A series of OID patterns can also be specified here, so that the test considers only those OIDs that match the specified pattern(s). For instance, *94.2*,*.*, where * indicates leading and/or trailing spaces.

DD Frequency

Refers to the frequency with which detailed diagnosis measures are to be generated for this test. The default is 1:1. This indicates that, by default, detailed measures will be generated every time this test runs, and also every time the test detects a problem. You can modify this frequency, if you so desire. Also, if you intend to disable the detailed diagnosis capability for this test, you can do so by specifying none against DD frequency.

Measurements made by the test
Measurement Description Measurement Unit Interpretation

Failed power supplies

Indicates the number of times this event was triggered due to power supply failure during the last measurement period.


The failure events may be generated due to the failure of the Power supply units of the Juniper EX Switch. If the failure events are not rectified within a certain pre-defined timeperiod, the switch will be shutdown automatically.

Ideally, the value of this measure should be zero. A high value is an indication of performance degradation of the Juniper EX Switch.