False positive failed power supply alarm is seen after a power cycle

book

Article ID: 168000

calendar_today

Updated On:

Products

XOS

Issue/Introduction

After a power cycle of the chassis, it is possible that a benign false positive power supply failed alarm will be generated.

After  a power cycle of the chassis, a minor power supply failed alarm is generated, such as the one seen below, even though LEDs are lit on all power supplies and "show environment" command shows the power feed is operational.


Minor Alarms: 

  Power Supply A                   Failed              Sat Jun  1 17:53:52 2013

Cause

There may be instances where X80-AC chassis do not properly report the status of each individual power supply bay. When this problem occurs and the “show environment” command is issued, the overall power supply status may or may not be reported correctly and individual bay information will be missing. 
 
This is a very intermittent issue with the most common causes of the error being power glitches or removing and restoring AC power to the system very quickly. 

Resolution

Once the system is in a state where the individual power supply bay information is not being reported, the condition can be cleared by gracefully powering the chassis down, waiting AT LEAST 15-20 seconds, and then powering the chassis back up. Please refer to article# 000004789 (How to stop and power down gracefully an X-Series chassis) for steps to gracefully shut down the chassis prior to powering it down.
 
It will still be possible for the chassis to enter into the failed condition in the future if a very short duration power "hit" or power "glitch" is observed. It is very important to note, however, that although the chassis is still susceptible to this reporting error, there is no loss of actual power supply capacity. This is a cosmetic reporting error only.