Deferred Error; Degraded Mode - IBM Ultrastar 36LZX Specifications

11.1.8 Deferred Error

Error code (71h) of sense data indicates that the Check Condition status returned is the result of an error
or exception condition that occurred during execution of a previous command for which Good status has
already been returned.
The drive creates an Deferred Error condition when
Ÿ Execution of a Format Unit command with the immediate bit of one ends with an error.
Ÿ Execution of a Write command with WCE (Write Cache Enable) bit of one ends with an error.

11.1.9 Degraded Mode

There are certain errors or conditions which may impair the ability of the drive to function normally.
Rather than fail hard the drive 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.
There are 3 conditions in the Degraded Mode:
Ÿ Spindle Motor Degrade is caused by one of the following conditions:
- Spindle Motor is not started by the option jumper setting (Disable Auto Spin Up)
- Spindle Motor is delayed from spinning up by the option jumper setting (Auto Start Delay)
- Spindle Motor was started (by POR or Unit Start command) and the Target is under Self Con-
figuration.
- Spindle Motor Failed to start.
- Spindle Motor was stopped by Unit Stop command after the Target successfully completed the
Self Configuration.
Ÿ Self Configuration Failure Degraded is caused by one of the following conditions:
- RAM Code, Configuration Sector Read Failure
- RAM Code, Configuration Sector Revision Mismatch
Ÿ Format Command Failure Degraded
This condition is caused when Format Unit command failed or was interrupted abnormally (Mode
Page 0, byte 5, bit 4 FDD controls Format Degraded mode).
Ultrastar 36LZX hard disk drive specifications
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