Description

In MX204 a hardware issue with the PEM or an issue with the power supply to the PEM may generate the Major alarm related to PEM 0 Input Voltage Out Of Range

Symptoms


The MX204 is powered using either AC or DC power. 
It supports two power supply modules (PSMs) located at the rear of the chassis in slots 0 and 1
The AC or DC power supply modules directly plug on to main board and are placed on the right side of the rear chassis.
Each power supply has a handle, an ejector lever, and status LEDs. The power supply modules connect to the PSM board,
which distributes the different output voltages produced by the power supply modules to the router components, depending on their voltage requirements.
When both the power supply modules are present, they share power almost equally within a fully populated system.
If the first power supply in a redundant configuration fails or is removed, the second power supply assumes the entire electrical load without interruption.
A single power supply provides the maximum configuration with full power for as long as the router is operational.
A second power supply can be installed for redundancy. The chassis is designed to support 1+1 feed redundancy.

DC Power Supply

DC Power Supply
AC Power Supply

AC Power Supply
MX204 Chassis | Juniper Networks

The command ‘show chassis alarms’ reports the major alarm: PEM 0 Input Voltage Out Of Range and  PEM 0 Not Powered.

Lab> show chassis alarms no-forwarding

1 alarms currently active
Alarm time               Class  Description
2021-05-26 15:12:58 EDT  Major  PEM 0 Input Voltage Out Of Range

Messages logs :

May 25 00:18:45  alarmd[8455]: Alarm set: PS SFXPC id=654311499, color=RED, class=CHASSIS, reason=PEM 0 Input Voltage Out Of Range

May 25 00:33:26  chassisd[8211]: CHASSISD_SNMP_TRAP6: SNMP trap generated: Power Supply failed (jnxContentsContainerIndex 2, jnxContentsL1Index 1, jnxContentsL2Index 0, jnxContentsL3Index 0, jnxContentsDescr PEM 0, jnxOperatingState 6)
May 25 00:33:26  chassisd[8211]: CHASSISD_SNMP_TRAP10: SNMP trap generated: FRU power off (jnxFruContentsIndex 2, jnxFruL1Index 1, jnxFruL2Index 0, jnxFruL3Index 0, jnxFruName PEM 0, jnxFruType 7, jnxFruSlot 0, jnxFruOfflineReason 2, jnxFruLastPowerOff 0, jnxFruLastPowerOn 6487)
May 25 00:36:40  alarmd[8455]: Alarm cleared: PS SFXPC id=402653259, color=RED, class=CHASSIS, reason=PEM 0 Not Powered

Chassisd logs :

May 25 00:33:23  PEM power status has changed, run power budget again
May 25 00:33:23  [Alarm SET] Object 75 reason 24 Device FRU PEM 0, reason PEM 0 No Power(PEM 0 Not Powered), color 1, slot 0 Alarm id 1258291224
May 25 00:33:23  send: red alarm set, device FRU PEM 0, reason PEM 0 Not Powered
May 25 00:33:26 CHASSISD_SNMP_TRAP6: SNMP trap generated: Power Supply failed (jnxContentsContainerIndex 2, jnxContentsL1Index 1, jnxContentsL2Index 0, jnxContentsL3Index 0, jnxContentsDescr PEM 0, jnxOperatingState 6)
May 25 00:33:26 CHASSISD_SNMP_TRAP10: SNMP trap generated: FRU power off (jnxFruContentsIndex 2, jnxFruL1Index 1, jnxFruL2Index 0, jnxFruL3Index 0, jnxFruName PEM 0, jnxFruType 7, jnxFruSlot 0, jnxFruOfflineReason 2, jnxFruLastPowerOff 0, jnxFruLastPowerOn 6487)


 

Solution

 
This may be a hardware issue with the PEM, or an issue with the power supply to the PEM
  • Check if either the power cord is not installed properly.
  • It is important to verify that the PEM is receiving the correct voltage (which may require an electrician) before assuming it is a hardware issue with the PEM.
  • Kindly perform a reseat for PEM Module with a support of 1+1 feed redundancy available, If still issue persist Kindly contact JTAC support for initiating a RMA.

Modification History

Version 1
 

Related Information

N/A