Chapter 9 Hardware installation and configuration issues
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Power supply unit fault LEDs
Each power supply unit (PSU) has three status LEDs. The asterisk (*) indicates a fault condition.
LED
Status
Type
PSU fault AC fault PSU OK
N/A
Color
Amber
Amber
Green
State
Off
AC power not present
On*
Off
PSU present, but not supplying power
Flashing
Off
Firmware download to PSU in progress
Off
On
AC power present, power switch is on, providing power
Off
Flashing AC power present, PSU on standby, other PSU providing power
On*
Communication with controller module (CM) lost
On*
N/A
Off
PSU hardware fault
On*
Off
PSU alert state or hardware fault: over temperature, over voltage, or over current
Off
On*
Off
AC power failed, PSU not providing power, other PSU providing power
Off
On*
AC power failed, PSU running on battery
Figure 63 Power supply unit fault LEDs
Identify 2U enclosure fault conditions
Fault conditions do not necessarily cause the storage enclosure to cease functioning. Fault conditions do
require a system administrator to take an appropriate action to clear the fault condition.
The controller modules (CMs) allow you to choose from multiple fault isolation methods. This section provides
the basic methodology used to locate faults within a storage system, then identify the affected FRUs.
When performing fault isolation and troubleshooting steps, select the option or options that best suit your site
environment. Use of any one of the following options is not mutually exclusive to the use of another option. The
order for the options is based on frequency of use.
To identify 2U enclosure fault conditions:
1. Monitor event and alert notifications through your host system interface or your preferred alternate method
and based on the notification settings you enable.
a. Event notifications: The system event logs record all system events and identifies the event type and its
severity.
b. Alert notifications: An alert reports a system fault, registers the type and severity, then tracks its
resolution.
2. Alerts fall into three categories, listed in order of severity. Resolve them, moving from most severe to least
severe.
