Hitachi HUS154530VLF400 User Manual

Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification

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The Drive provides the capability to remove media defects without reducing capacity. If the mode parameter bit ARRE is 
active, the Drive will automatically reallocate LBA's determined to be defective. For those LBA's where the error is unrecov-
erable or the initiator elects to not have the Drive automatically reallocate LBA's, the Drive will recommend reassignment of 
the LBA.

Recovery from a failed reassignment consists of the following actions:

•

Updating the defect descriptor to remove the LBA's that have been successfully reassigned and then retry the Reas-

sign Blocks command. The LBA contained in the Command Specific Information field of the Sense Data is the LBA 
in the first defect descriptor that was not reassigned because of the failure. If the command failed because of an unre-
coverable read error other than those specified in the defect descriptor, add this LBA to the defect descriptor and retry 
the command. Refer to Section 19.26, “REASSIGN BLOCKS (07)” on page 238, for additional information.

•

If the retried Reassign Blocks (07) command completes successfully, returning to normal processing.

•

If the retried Reassign Blocks (07) command fails, servicing the drive using the service guidelines recommended in 

Section 21.21.1, “Drive Service Strategy” on page 339.

The Drive will follow a logical recovery procedure for nondata errors. The initiator options for non-data errors are limited to 
logging the error, retrying the failing command, or replacing the drive.

These recovery procedures assume the initiator practices data back-up and logs errors at the system level for interrogation by 
service personnel.

The Drive is busy performing an operation. This is not an error condition. The initiator can test for completion of the opera-
tion by issuing Test Unit Ready (00) (or media access) commands.

•

If  the  Test Unit Ready (00) (or media access) command completes with Check Condition Status then issue a Request 

-  If the specified recovery procedure for the sense data is for a condition other than drive busy, follow the recovery 

procedure for the condition reported.

-  If the specified recovery procedure for the sense data is for a drive busy condition, then continue re-issuing the Test 

Unit Ready (00) and Request Sense commands for the duration of a media access time-out or until the drive returns 
Good Status. 

-  If the drive has been busy for longer than the limit specified in Section 21.20, “Command Time out Limits” on 

page 337, then service the drive using the service guidelines recommended in Section 21.21.1, “Drive Service 
Strategy” on page 339. Otherwise return to normal processing.

•

If  the  Test Unit Ready (00) (or media access) command completes with Good Status, then return to normal process-

ing.

The initiator should retry the failing command. 

1.   If the retry of the failing command completes with Good Status or recovered Sense Key, follow the recovery procedure 

in Section 21.21.4.3, “Recovered Drive Error” on page 343.

2.   If the retry of the failing command completes with hardware error sense, verify there is no outside cause (e.g., power 

supply) for the failure, then retry the failing command. 
a.   If the retry of the failing command completes with Good Status, follow the recovery procedure in next Section 

b.   If the retry of the failing command completes with Recovered sense or Hardware error sense, then service the drive 

using the service guideline recommended in Section 21.21.1, “Drive Service Strategy” on page 339.