7.3FC-AL system errors

Information on the reporting of operational errors or faults across the interface is given in the Fibre Channel Interface Manual. The FCP Response returns information to the host about numerous kinds of errors or faults. The Receive Diagnostic Results reports the results of diagnostic operations performed by the drive.

Status returned by the drive to the initiator is described in the Fibre Channel Interface Manual. Status reporting plays a role in systems error management and its use in that respect is described in sections where the various commands are discussed.

7.4Background Media Scan

Background Media Scan (BMS) is a self-initiated media scan. BMS is defined in the T10 document SPC-4 available from the T10 committee. BMS performs sequential reads across the entire pack of the media while the drive is idle. In RAID arrays, BMS allows hot spare drives to be scanned for defects prior to being put into service by the host system. On regular duty drives, if the host system makes use of the BMS Log Page, it can avoid placing data in suspect locations on the media. Unreadable and recovered error sites will be logged or reallocated per ARRE/AWRE settings.

With BMS, the host system can consume less power and system overhead by only checking BMS status and results rather than tying up the bus and consuming power in the process of host-initiated media scanning activ- ity.

Since the background scan functions are only done during idle periods, BMS causes a negligible impact to sys- tem performance. The first BMS scan for a newly manufactured drive is performed as quickly as possible to verify the media and protect data by setting the “Start time after idle” to 5ms, all subsequent scans begin after 500ms of idle time. Other features that normally use idle time to function will function normally because BMS functions for bursts of 800ms and then suspends activity for 100ms to allow other background functions to operate.

BMS interrupts immediately to service host commands from the interface bus while performing reads. BMS will complete any BMS-initiated error recovery prior to returning to service host-initiated commands. Overhead associated with a return to host-servicing activity from BMS only impacts the first command that interrupted BMS, this results in a typical delay of about 1 ms.

7.5Media Pre-Scan

Media Pre-Scan is a feature that allows the drive to repair media errors that would otherwise have been found by the host system during critical data accesses early in the drive’s life. The default setting for Media Pre-Scan is enabled on standard products. Media Pre-Scan checks each write command to determine if the destination LBAs have been scanned by BMS. If the LBAs have been verified, the drive proceeds with the normal write command. If the LBAs have not been verified by BMS, Pre-Scan will convert the write to a write verify to certify that the data was properly written to the disc.

Note. During Pre-Scan write verify commands, write performance may decrease by 50% until Pre-Scan completes. Write performance testing should be performed after Pre-Scan is complete. This may be checked by reading the BMS status.

To expedite the scan of the full pack and subsequently exit from the Pre-Scan period, BMS will begin scanning immediately when the drive goes to idle during the Pre-Scan period. In the event that the drive is in a high transaction traffic environment and is unable to complete a BMS scan within 24 power on hours BMS will dis- able Pre-Scan to restore full performance to the system.

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Seagate ST31000640FC, ES.2 FC manual FC-AL system errors, Background Media Scan, Media Pre-Scan
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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.
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