IBM DDRS-39130 - Ultrastar 9.1 GB Hard Drive, Specifications

Page: 195 / 228

10.1.9 Degraded Mode
There are certain errors or conditions which may impair the file's ability to function normally. Rather than
fail hard, the file is designed to be as responsive as possible. Also, in most cases, some action on the part of
the initiator may be used to restore normal operation.
This mode of limited operation is called Degraded
Mode.
10.1.10 Degraded mode handling
If any degraded mode condition occurs an initiator will receive a sense key of Hardware error (4h) in the
next sense data requested. After clearing the sense key, the drive accepts commands according to the status
of the degraded mode.
The following table shows the degraded mode status with acceptable commands and aditional sense codes.
If a degraded mode exists, the Hardware error condition caused by the degrade mode will be recreated after
every POR, SCSI Reset or Bus Device Reset message.
The following list shows the various operation
modes.
10.1.10.1 Degraded Mode Entry Condition/Consequence State
Degraded
Mode Entry Reason Accepting
Request Description and sense code
Power on
Self Test
fail
Failure of a
start-up
sequence Request
Sense
Inquiry
Start/Stop
unit
Write
Buffer(except
download
and save)
The integrity of the drive is questionable.
Sense code =
4080 (diagnostic fail )
Spin-up Can not start up
motor
Request
Sense
Inquiry
Start/Stop
unit
Write
Buffer(except
download
and save)
Return Spin-up Degraded Mode.
Sense code = 0400
Additional Information
185