Seagate ST373455LC DST Failure Definition, Implementation, State of the drive prior to testing

Models: ST3146855LC ST373207LW ST373455LC ST3300655LC ST3146855LW ST373455LW ST3300655LW

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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 disc

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. Refer to the SCSI Commands Reference Manual, part number 100293068, for additional information about invoking DST.

6.2.6.2.3Short and extended tests

DST has two testing options:

1.short

2.extended

These testing options are described in the following two subsections.

Each test consists of three segments: an electrical test segment, a servo test segment, and a read/verify scan segment.

Cheetah 15K.5 SCSI Product Manual, Rev. J

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Seagate ST373455LC, ST3146855LC DST Failure Definition, Implementation, State of the drive prior to testing, Invoking DST