The alternate block allocation is executed by the FORMAT UNIT command, the REASSIGN BLOCKS command, or the automatic alternate block allocation. Refer to Chapter 3 “Command Specification” and Subsection 5.3.2 “Auto alternate block allocation processing” of the SCSI Logical Interface Specifications for details of specifications on these commands. The logical data block is allocated to the next physically continued sectors after the above sector slip treatment is made. On the other hand, the logical data block is allocated to spare sectors which are not physically consecutive to the adjacent logical data blocks. If a command which processes several logical data blocks is specified, the HDD processes those blocks in ascending order of logical data block.

(1)Alternate block allocation during FORMAT UNIT command execution

When the FORMAT UNIT command is specified, the allocation of the alternate block to those defective sectors included in the specified lists (P, G, or D) is continued until all spare sectors in the same cell are used up. When they are used up, unused spare sectors in the alternate cylinder are allocated to the subsequent sectors in the cylinder by means of alternate sector treatment. Figure 3.7 is examples of the alternate block allocation during the FORMAT UNIT command execution.

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Fujitsu MAW3300NC/NP, MAW3073NC/NP, MAW3147NC/NP manual

MAW3147NC/NP, MAW3073NC/NP, MAW3300NC/NP specifications

Fujitsu has established itself as a key player in the world of hard disk drives, and their MAW3073NC/NP, MAW3300NC/NP, and MAW3147NC/NP models showcase exemplary engineering and innovative technology. These drives are designed primarily for enterprise applications, providing robust performance, reliability, and data integrity in demanding environments.

One of the standout features of the Fujitsu MAW series is its high storage capacity. The MAW3073NC/NP model comes with a generous 73 GB capacity, while the MAW3300NC/NP boasts 300 GB, and the MAW3147NC/NP offers 147 GB of storage. This range makes them suitable for various applications, from databases to data-intensive software.

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In terms of physical design, these drives are built to endure the rigors of high-demand environments. They feature a robust construction that allows for efficient heat dissipation, minimizing the risks associated with overheating. Additionally, their form factor is designed for easy integration into various server and storage systems, making them versatile solutions for IT infrastructure.

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