Chapter 6 Disk Media Management; Defect Management - Fujitsu MAX3073NC - SCSI,80, Dell DC961,Hard Drive Scsi Logical Interface Specifications

CHAPTER 6
Disk Media Management
In this chapter, disk media defect management methods, treatment methods for media defects which occur during
operation, reinitialization procedures and other disk media management methods are discussed. Furthermore, see
Chapter 3, "Data Format" in the "Product Manual" concerning details of the data recording format on the disk
media.
6.1

Defect Management

(1) Defect lists
Information on the positions of defects in the disk media are managed by the types of defect list shown
below. See the description of the FORMAT UNIT command (Section 3.3.1) concerning methods for
using the defect lists.
• P List Defect position information at the point when the disk drive was shipped from the factory is
recorded in this list. The defective portions included in this list are permanent defects, and
when the disk media is initialized, it is necessary that this list be used and alternate block
processing be executed.
• D List This list includes defect position information specified by the INIT in the FORMAT UNIT
command when initializing the disk media.
• C List This list contains information on the positions of defective blocks detected during the data
block Verify operation (Certification) after initialization by the FORMAT UNIT command.
This information is generated internally by the IDD when the FORMAT UNIT command is
executed.
• G List This list is composed from the defective logical data block position information specified by
the INIT in the REASSIGN BLOCKS command, defective logical data block position
information from alternate blocks which have been allocated by the IDD's auto alternate
block allocation processing, information specified as the D List and information generated
as the C List.
The P List and G List are recorded in the system space on the disk media. The INIT can read the
contents of these lists by the READ DEFECT DATA command.
C141-C010
6.1 Defect Management
6.2 Disk Media Initialization
6.3 Data Block Verification Methods (Recommended)
6.4 Alternate Block Allocation Processing
6-1