7.0Defect 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 FC system error con- siderations (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 7.4)

Media Pre-Scan (see Section 7.5)

Deferred Auto-Reallocation (see Section 7.6)

Idle Read After Write (see Section 7.7)

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

7.1Drive 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 Fibre Channel Interface Manual. Also, more information on the drive Error Recovery philosophy is presented in the Fibre Channel Interface Manual.

7.2Drive 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 Fibre Channel 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 ST31000640FC, ES.2 FC Defect and error management, Drive internal defects/errors, Drive error recovery procedures

ST31000640FC, ES.2 FC specifications

The Seagate ES.2 FC, model ST31000640FC, is a high-performance hard drive designed specifically for enterprise environments. This drive is engineered to provide reliable and efficient data storage, catering to the demands of critical business applications, data centers, and server infrastructures.

One of the standout features of the ST31000640FC is its large storage capacity. With a 1TB capacity, it offers ample space for storing vast amounts of data, making it an excellent choice for businesses that require extensive storage solutions. This capacity enables the drive to support extensive databases, applications, and virtualized environments without compromising performance.

The Seagate ES.2 FC utilizes Fibre Channel (FC) interface technology, which is known for its high-speed data transfer capabilities. Operating at 4 Gbps, this interface facilitates faster communication between the drive and the server, significantly enhancing overall system performance. The Fibre Channel technology also improves data integrity through its ability to manage large amounts of data traffic efficiently.

In terms of performance specifications, the ST31000640FC boasts a rotational speed of 7200 RPM and a sustained data transfer rate that offers quick access to information. Additionally, it features an advanced caching mechanism that optimizes read and write operations, ensuring rapid data retrieval and improved application responsiveness.

The drive's advanced error recovery and data protection mechanisms, such as the Seagate PowerTrim technology, work to minimize downtime and data loss. This is particularly crucial for enterprise applications that demand high availability and reliability. PowerTrim intelligently manages the drive’s internal resources to enhance performance and durability.

Another essential characteristic of the Seagate ES.2 FC is its enterprise-grade reliability. It boasts a mean time between failures (MTBF) rating of 1.2 million hours, indicating its robustness for continuous operation in demanding environments. Furthermore, it is designed to operate in a range of temperatures, ensuring consistent performance across various operational conditions.

Lastly, the Seagate ES.2 FC incorporates vibration tolerance and advanced acoustic performance features, which help to reduce noise and ensure quieter operation in data center environments. This makes it an attractive option for enterprises looking to optimize their infrastructure while minimizing disturbances.

In summary, the Seagate ES.2 FC, ST31000640FC hard drive is an excellent choice for enterprises seeking a balance of large storage capacity, high-speed performance, and reliability in a Fibre Channel environment. With its array of technologies and robust characteristics, it meets the rigorous demands of modern business storage needs.