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 ST9300603SS manual Defect and error management, Drive internal defects/errors, Drive error recovery procedures
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ST9146803SS, ST9300603SS, ST9300503SS, ST9146603SS, ST9146703SS specifications

Seagate has long been a key player in the storage technology industry, and its enterprise-class hard drives such as the ST9300503SS, ST9300403SS, ST9146603SS, ST9146803SS, and ST9146703SS stand out for their performance, reliability, and innovative features. Designed primarily for use in data centers and server environments, these drives offer a range of specifications suited for high-demand applications.

The Seagate ST9300503SS is a 300GB 2.5-inch SAS (Serial Attached SCSI) hard drive that operates at 10,000 RPM, which is essential for ensuring rapid data access. It provides a data transfer rate of 6 Gb/s and features Seagate's AgileArray technology, which enhances RAID performance and reliability by improving data integrity and optimizing power consumption. The drive is also designed to withstand the rigors of enterprise use, boasting a mean time between failures (MTBF) rating of 1.6 million hours.

In contrast, the ST9300403SS offers a similar 300GB capacity and speed, but with slight variations in features that make it better suited for specific applications. This drive also supports SAS 2.0 and includes features that enhance error recovery and data protection.

The ST9146603SS is another powerhouse, providing 146GB of storage. Operating at the same high spindle speed of 10,000 RPM, it is optimized for low-latency performance. This makes it highly suitable for transactional applications and environments where quick access to data is crucial. Like its counterparts, this drive is built with robust technologies that ensure reliable operation and enhanced data security.

The ST9146803SS bumps up the storage capacity to 300GB while maintaining the same impressive speed and performance features. Its incorporation of Seagate’s SeaTach technology allows for advanced communication protocols, which facilitate faster data transfers and lower latency.

Finally, the ST9146703SS also offers 146GB of storage and is known for its energy efficiency features that reduce operational costs in large-scale deployments. All these drives support a wide range of operating systems, making them versatile picks for businesses looking to upgrade their storage solutions.

Overall, the Seagate ST9300503SS, ST9300403SS, ST9146603SS, ST9146803SS, and ST9146703SS are essential components in any enterprise environment, delivering high performance, reliability, and advanced technology features that meet the critical demands of modern data storage.
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