6.2.6Drive Self Test (DST)

Drive Self Test (DST) is a technology designed to recognize drive fault conditions that qualify the drive as a failed unit. DST validates the functionality of the drive at a system level.

There are two test coverage options implemented in DST:

1.Extended test

2.Short test

The most thorough option is the extended test that performs various tests on the drive and scans every logical block address (LBA) of the drive. The short test is time-restricted and limited in length—it does not scan the entire media surface, but does some fundamental tests and scans portions of the media.

If DST encounters an error during either of these tests, it reports a fault condition. If the drive fails the test, remove it from service and return it to Seagate for service.

6.2.6.1DST failure definition

The drive will present a “diagnostic failed” condition through the self-tests results value of the diagnostic log page if a functional failure is encountered during DST. The channel and servo parameters are not modified to test the drive more stringently, and the number of retries are not reduced. All retries and recovery processes are enabled during the test. If data is recoverable, no failure condition will be reported regardless of the number of retries required to recover the data.

The following conditions are considered DST failure conditions:

•Seek error after retries are exhausted

•Track-follow error after retries are exhausted

•Read error after retries are exhausted

•Write error after retries are exhausted

Recovered errors will not be reported as diagnostic failures.

6.2.6.2Implementation

This section provides all of the information necessary to implement the DST function on this drive.

6.2.6.2.1State of the drive prior to testing

The drive must be in a ready state before issuing the Send Diagnostic command. There are multiple reasons why a drive may not be ready, some of which are valid conditions, and not errors. For example, a drive may be in process of doing a format, or another DST. It is the responsibility of the host application to determine the “not ready” cause.

While not technically part of DST, a Not Ready condition also qualifies the drive to be returned to Seagate as a failed drive.

A Drive Not Ready condition is reported by the drive under the following conditions:

•Motor will not spin

•Motor will not lock to speed

•Servo will not lock on track

•Drive cannot read configuration tables from the disk

In these conditions, the drive responds to a Test Unit Ready command with an 02/04/00 or 02/04/03 code.

6.2.6.2.2Invoking DST

To invoke DST, submit the Send Diagnostic command with the appropriate Function Code (001b for the short test or 010b for the extended test) in bytes 1, bits 5, 6, and 7.

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Constellation ES.1 SAS Product Manual, Rev. E

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Seagate ST500NM0001 manual Drive Self Test DST, DST failure definition, Implementation, State of the drive prior to testing
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ST2000NM0001, ST1000NM0041, ST500NM0001, ST2000NM0021, ST1000NM0021 specifications

Seagate is a renowned leader in data storage solutions, offering a wide array of hard disk drives (HDDs) suitable for various applications. Among their product lineup, the Seagate ST2000NM0041, ST500NM0021, ST500NM0041, ST1000NM0001, and ST1000NM0021 stand out as reliable options tailored for enterprise environments and general storage needs.

The Seagate ST2000NM0041 is a 2TB 7200 RPM drive designed for high-performance workloads in data centers. One of its key features is the use of the SATA III interface, providing data transfer speeds of up to 6 Gbps, ensuring quick access to data. This model supports advanced error recovery controls and features enhanced power management capabilities, which contribute to its reliable performance and energy efficiency.

Next, the ST500NM0021 and ST500NM0041 are both 500GB drives that cater to different consumer needs. The ST500NM0021 is a 5400 RPM drive, typically used in scenarios where lower power consumption is vital, such as in compact systems or external storage configurations. Its efficient design enables quieter operation, making it ideal for environments that require minimal noise. Conversely, the ST500NM0041 operates at a speed of 7200 RPM, making it suitable for more demanding applications that require swift read and write speeds. Both models utilize Serial ATA for connectivity, ensuring compatibility with a wide range of systems.

The ST1000NM0001 and ST1000NM0021 are 1TB drives that provide versatility across different platforms. Similar to their 500GB counterparts, the ST1000NM0001 features a 7200 RPM speed, optimizing performance for applications requiring faster data processing. In contrast, the ST1000NM0021 operates at 5400 RPM, designed for users prioritizing energy efficiency over speed, like in desktop and external storage solutions. Each of these drives supports advanced technologies such as Native Command Queuing (NCQ), which enhances performance by allowing multiple commands to be executed simultaneously.

Overall, the Seagate ST series hard drives offer flexible storage options for a variety of applications. With their robust features, including varied RPM speeds, power management, and compatibility with SATA connections, these drives cater to the needs of both consumer and enterprise markets, establishing Seagate as a trusted provider in the storage arena.
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