- IBM switch Users and Maintenance Guide

Table 17. Symptom-to-FRU index (continued)
Problem
indicator Component Possible cause Possible solutions
All green LEDs off All CRUs Subsystem
power is off
Check that all storage-server
power cords are plugged in and
the power switches are on. If
applicable, check that the main
circuit breakers for the rack
cabinet are turned on.
AC power failure Check the main circuit breaker
and ac outlet.
Power supply
failure
Replace the power supply.
Midplane failure Have the midplane replaced
(service technician only).
Amber LED
flashing
Drive CRUs Drive identify is in
process
No corrective action is needed.
One or more
green LEDs off
Power supply
CRUs
Power cord
unplugged or
switches turned
off
Make sure that the power cord is
plugged in and the power-supply
switches are turned on.
All drive CRUs Midplane failure Have the midplane replaced
(service technician only).
Front panel Power supply
problem
Make sure that the cords are
plugged in and power supplies
are turned on.
Hardware failure If any other LEDs are on, replace
the midplane (service technician
only).
Battery Battery failure Replace the battery.
Cache active The cache is
disabled
Use the DS4000 Storage
Manager client to enable the
logical drive read and write cache
settings.
The cache
memory has
failed
Replace the RAID controller.
The cache
battery has failed
Use the DS4000 Storage
Manager client to check and
replace the battery.
Host loop Host or switch is
off or has failed
Check if host or switch is on.
Replace attached devices that
have failed.
Fibre-channel
cable has failed
Ensure that the fibre-channel
cables are undamaged and
properly connected.
SFP has failed Ensure SFP is seated properly;
replace SFP.
RAID controller
has no power or
has failed
Ensure that the unit is powered
on. Replace RAID controller.
Chapter 6. Hardware maintenance 113