Checking The Leds - IBM TotalStorage 300 Service Manual

procedure that you must perform. In some cases (such as loss of redundancy in
various components), the fault LED does not turn on. Only the storage-management
software can detect the failure. For example, the recovery procedure for a
Predictive Failure Analysis (PFA) flag (impending drive failure) on a drive varies
depending on the drive status (hot spare, unassigned, RAID level, current logical
drive status, and so on). Depending on the circumstances, a PFA flag on a drive
can indicate a high risk of data loss (if the drive is in a RAID 0 volume) or a minimal
risk (if the drive is unassigned). Only the storage-management software can identify
the risk level and provide the necessary recovery procedures.
Note: For PFA flags, the General-system-error LED and Drive fault LEDs do not
Attention:

Checking the LEDs

The LEDs display the status of the IBM NAS 300 components. Green LEDs indicate
a normal operating status; amber LEDs indicate a possible failure.
It is important to check all the LEDs on the front and back of the components when
you turn on the power. In addition to checking for faults, you can use the LEDs on
the front of the storage server to determine if the drives are responding to I/O
transmissions from the network.
See the following diagram and Table 8 for information about the front-panel LEDs.
For information about rear-panel LEDs, see:
v Table 9 on page 37
v Table 10 on page 39
v Table 11 on page 39
36
IBM NAS 300 Service Guide
turn on, so checking the LEDs will not notify you of the failure, even if the
risk of data loss is high. Recovering from a RAID storage controller failure
might require you to perform procedures other than replacing the component
(such as backing up the logical drive or failing a drive before removing it).
The storage-management software gives these procedures.
Not following the software-recovery procedures can result in data loss.
Power-on LED
General-system-
error LED
Tray handle
Table 8. LEDs located on front panel of a RAID storage controller
LED Color
Hot-swap
drive CRU
Latch
Drive fault LED
1
Operating states
Drive activity LED