Ultrastar C10K600 OEM Specification

18.26 REASSIGN BLOCKS (07)

Table 156: REASSIGN BLOCKS (07)

Byte

7 6 5

Bit

4 3

Command Code = 07h

2 1 0

2

3

4

5

0

1 Reserved = 0

Reserved = 0

Reserved = 0

VU = 0 Reserved = 0 FLAG LINK

The REASSIGN BLOCKS command requests the drive to reassign a logical block to an available spare. The REASSIGN

BLOCKS command attempts to allocate spare blocks on a spare track. The LBA is transferred to the drive during the DATA

OUT phase. One to four blocks may be specified for relocation per REASSIGN BLOCKS command.

Reassignment is complete upon the completion of the REASSIGN BLOCKS command. At this time, the defective logical block address has been added to the Glist.

All data is preserved during a reassign command except for the target LBA data. The Mode Page 0h DRRT (Disable Restore

Reassign Target) bit determines if the reassign blocks command will attempt to recover the Target LBA data. If the Target cannot recover the data at the Target LBA then the Initiator will have to restore the data after the REASSIGN BLOCKS command completes successfully.

If the reassignment begins to move data and is interrupted or fails to complete successfully, the Target enters a degraded mode of operation. In this mode data can be read but writing to the drive is prohibited.

Upon successful completion of this command, the location of the physical sectors reassigned during the command are added to the Glist. The reassigned sectors are marked defective and cannot be accessed again until after a format operation discards the

Glist.

HGST Ultrastar C10K600 (SAS) Hard Disk Drive Specification

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Following is the format of the data sent by the Initiator during the DATA OUT phase.

Table 157: Format of Reassign Blocks data

Byte

0

1

2-3

7 6 5

Bit

4

Reserved = 0

Reserved = 0

3

(MSB) Defect List Length = 4/8/12/16

2 1

(LSB)

(MSB)

4-7 Defect Logical Block Address 1

(LSB)

(MSB)

8-11 Defect Logical Block Address 2

(LSB)

(MSB)

12-15 Defect Logical Block Address 3

(LSB)

(MSB)

16-19 Defect Logical Block Address 4

(LSB)

•

• Defect List Length must be 4, 8, 12, or 16. Otherwise, the drive returns Check Condition with a sense key of Illegal

Request.

Defective Logical Block Address is four bytes in length. The Initiator can specify from 1 to 4 Defective Logical

Block Addresses according to the Defect List Length from 4 to 16, respectively. LBAs are not required to be in ascending order.

HGST Ultrastar C10K600 (SAS) Hard Disk Drive Specification

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