10.0Defect and error management

Seagate continues to use innovative technologies to manage defects and errors. These technologies are designed to increase data integrity, perform drive self-maintenance, and validate proper drive operation.

SCSI defect and error management involves drive internal defect/error management and SAS system error considerations (errors in communications between the initiator and the drive). In addition, Seagate provides the following technologies used to increase data integrity and drive reliability:

•Background Media Scan (see Section 10.4)

•Media Pre-Scan (see Section 10.5)

•Deferred Auto-Reallocation (see Section 10.6)

•Idle Read After Write (see Section 10.7)

The read error rates and specified storage capacities are not dependent on host (initiator) defect management routines.

10.1Drive internal defects/errors

During the initial drive format operation at the factory, media defects are identified, tagged as being unusable, and their locations recorded on the drive primary defects list (referred to as the “P’ list and also as the ETF defect list). At factory format time, these known defects are also reallocated, that is, reassigned to a new place on the medium and the location listed in the defects reallocation table. The “P” list is not altered after factory formatting. Locations of defects found and reallocated during error recovery procedures after drive shipment are listed in the “G” list (defects growth list). The “P” and “G” lists may be referenced by the initiator using the Read Defect Data command.

Details of the SCSI commands supported by the drive are described in the SAS Interface Manual. Also, more information on the drive Error Recovery philosophy is presented in the SAS Interface Manual.

10.2Drive error recovery procedures

When an error occurs during drive operation, the drive, if programmed to do so, performs error recovery proce- dures to attempt to recover the data. The error recovery procedures used depend on the options previously set in the Error Recovery Parameters mode page. Error recovery and defect management may involve using sev- eral SCSI commands described in the SAS Interface Manual. The drive implements selectable error recovery time limits required in video applications.

The error recovery scheme supported by the drive provides a way to control the total error recovery time for the entire command in addition to controlling the recovery level for a single LBA. The total amount of time spent in error recovery for a command can be limited using the Recovery Time Limit bytes in the Error Recovery mode page. The total amount of time spent in error recovery for a single LBA can be limited using the Read Retry Count or Write Retry Count bytes in the Error Recovery mode page.

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Seagate ST32000646NS manual Defect and error management, Drive internal defects/errors, Drive error recovery procedures
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ST4000NM0053, ST4000NM0023, ST32000444SSIM, ST32000646NS, ST3000NM0063 specifications

Seagate is a prominent name in the storage industry, renowned for its high-performance hard disk drives (HDDs). Among its popular enterprise offerings are models like the ST2000NM0043, ST32000645NS, ST3000NM0043, ST2000NM0033, and ST2000NM0023, which cater to various data center and server needs.

The Seagate ST2000NM0043 is a 2TB 7200 RPM SATA drive designed for high availability and performance in enterprise environments. It features a 128MB cache, ensuring efficient data transfer speeds and quick access to frequently used data. This model boasts a mean time between failures (MTBF) of 1.4 million hours, emphasizing its reliability for continuous operation in demanding applications.

The ST32000645NS, offering 2TB of storage and a 7200 RPM spindle speed, is ideal for environments where large amounts of data need to be stored and accessed quickly. It supports SAS interfaces, providing enhanced data integrity and improved system performance. With its aggressive power management features, this model strikes a balance between performance and energy efficiency, making it suitable for both traditional data centers and cloud applications.

The ST3000NM0043 stands out with a capacity of 3TB, further addressing the growing need for more substantial storage solutions. Like its counterparts, it operates at 7200 RPM and is equipped with advanced caching mechanisms that help enhance overall performance. Its high durability and enterprise-grade features make it a preferred choice for storage-intensive applications.

The ST2000NM0033 focuses on delivering storage solutions for environments needing both capacity and reliability. With its 2TB capacity and 7200 RPM rotation speed, it provides an effective solution for businesses looking to balance workload and storage needs without compromising performance. This model also features Seagate's advanced technology that optimizes workflow and minimizes latency.

Lastly, the ST2000NM0023 mirrors many of the features found in its siblings, offering a 2TB capacity and optimized for high reliability and performance. With Seagate's commitment to innovating in the HDD space, features such as self-monitoring, analysis, and reporting technology (SMART) help maintain the drive's health and prevent potential failures.

In conclusion, Seagate's range of HDDs, exemplified by the ST2000NM0043, ST32000645NS, ST3000NM0043, ST2000NM0033, and ST2000NM0023, reflects a dedication to providing robust, high-capacity storage solutions. Their advanced technologies, reliability ratings, and performance features make them ideal choices for enterprise environments demanding efficiency and durability.
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