Checking The Leds - IBM TotalStorage DS4100 Installation, User's, And Maintenance Manual

v Locate the failed component
v Determine the recovery procedures to repair the failure
Although the storage server has fault LEDs, these lights do not necessarily indicate
which component has failed or needs to be replaced, or which type of recovery
procedure you must perform. In some cases (such as loss of redundancy in various
components), the fault LED does not turn on. Only the DS4000 Storage Manager
client can detect the failure.
For example, the recovery procedure for a Predictive Failure Analysis
(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
DS4000 Storage Manager client 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
Recovering from a storage-server 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 DS4000 Storage Manager client gives these
procedures.
Attention:

Checking the LEDs

The LEDs display the status of the storage server and 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 storage server
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 host.
For information about the LEDs on the front of the storage server, see:
v Figure 57 on page 72
v Table 12 on page 72
For information about the LEDs on the back of the storage server, see:
v Figure 59 on page 74
v Table 13 on page 73
v Table 14 on page 74
turn on, so checking the LEDs will not notify you of the failure, even if the
risk of data loss is high.
Not following the software-recovery procedures can result in data loss.
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Chapter 4. Operating the storage server
(PFA) flag
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