IBM TotalStorage DS4100 Installation, User's, And Maintenance Manual page 146

Table 17. Symptom-to-FRU index (continued)
Problem
indicator
One or more
green LEDs off
(continued)
Intermittent or
sporadic power
loss to the storage
server
Unable to access
drives
Random errors
114
IBM TotalStorage DS4100 Storage Server: Installation, User's, and Maintenance Guide
Component Possible cause
Expansion loop Drives are
improperly
installed or not
installed
RAID controller
has no power or
has failed
Impending drive
failure
Externally
attached
expansion port
device has failed
Some or all CRUs Defective ac
power source or
partially
plugged-in power
cord
Power supply
has failed
Midplane has
failed
Drives and Fibre-channel
expansion loop cabling has
failed.
RAID controller
has failed
SFP has failed
Subsystem Midplane has
failed
Possible solutions
Ensure that the drives are
properly installed.
Ensure that the unit is powered
on. Replace the RAID controller.
A bad drive or drives can issue
LIPs that cause the drive
expansion loop to go down
momentarily. Use the RLS
function in the DS4000 Storage
Manager client to determine
which drives are bad. Replace
the bad drives.
Replace the expansion unit SFP
or fibre-channel cable.
Check the ac power source;
verify that the ac circuit that the
storage server connects to is not
being overloaded. Reseat all
installed power cables and power
supplies. If applicable, check the
power components. Replace
defective power cords.
Check for a Fault LED on the
power supply, and replace the
failed CRU.
Have the midplane replaced
(service technician only).
Ensure that the fibre-channel
cables are undamaged and
properly connected.
Replace the RAID controller.
Ensure SFP is seated properly;
replace SFP.
Have the midplane replaced
(service technician only).