Seagate Elite 9, Руководство по эксплуатации продукта

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Elite 9 Product Manual, Rev. C 19
6.0 Reliability specifications
The following reliability specifications assume correct host and drive
interface, including all interface timings, power supply voltages, and
environmental requirements.
Seek error rate Less than 10 errors in 10
8
seeks
Recoverable error rate Less than 10 errors in 10
11
bits transferred
(using default settings)
Unrecovered data Less than 1 sector in 10
14
bits transferred
Miscorrected data Less than 1 sector in 10
21
bits transferred
MTBF 500,000 hours
Service life 5 years
Preventive maintenance None required
6.1 Error rates
The error rates stated in this manual assume the following:
• The drive is operated using DC power as defined in Section 7.2.
• The drive has been formatted with SCSI format commands.
• Errors caused by media defects or host system failures are excluded from
error rate computations. Refer to Section 9.0.
6.1.1 Environmental interference
When evaluating system operation under conditions of electromagnetic
interference (EMI), the performance of the drive within the system is
considered acceptable if the drive does not generate an unrecoverable
condition.
An unrecoverable error or condition is defined as one that:
• is not detected and corrected by the drive itself;
• is not capable of being detected from the error or fault status provided
through the drive or SCSI interface; or
• is not capable of being recovered by normal drive or system recovery
procedures without operator intervention.
6.1.2 Write errors
Write errors can occur as a result of media defects, environmental interfer-
ence, or component malfunction. Therefore, write errors are not predictable
as a function of the number of bits passed.
If an unrecoverable write error occurs because of a component malfunction
in the drive, the error is classified as a failure affecting MTBF. Unrecoverable
write errors are those that cannot be corrected within two attempts at writing
the record with a read verify after each attempt (excluding media defects).