Seagate Enterprise Capacity 3.5 HDD/Constellation ES Constellation ES (.1) SAS - Page 18

5.0 RELIABILITY SPECIFICATIONS The following reliability specifications assume correct host and drive operational interface, including all interface timings, power supply voltages, environmental requirements and drive mounting constraints. Seek error rate: Read Error Rates1 Recovered Data Unrecovered Data Miscorrected Data Interface error rate: Less than 10 errors in 108 seeks Less than 10 errors in 1012 bits transferred (OEM default settings) Less than 1 sector in 1015 bits transferred Less than 1 sector in 1021 bits transferred Less than 1 error in 1012 bits transferred Mean Time Between Failure (MTBF): 1,200,000 hours Annualized Failure Rate (AFR): 0.73% Preventive maintenance: None required 1. Error rate specified with automatic retries and data correction with ECC enabled and all flaws reallocated. 5.1 ERROR RATES The error rates stated in this manual assume the following: • The drive is operated in accordance with this manual using DC power as defined in paragraph 6.3, "DC power requirements." • Errors caused by host system failures are excluded from error rate computations. • Assume random data. • Default OEM error recovery settings are applied. This includes AWRE, ARRE, full read retries, full write retries and full retry time. 5.1.1 Recoverable Errors Recoverable errors are those detected and corrected by the drive, and do not require user intervention. Recoverable Data errors will use correction, although ECC on-the-fly is not considered for purposes of recovered error specifications. Recovered Data error rate is determined using read bits transferred for recoverable errors occurring during a read, and using write bits transferred for recoverable errors occurring during a write. 5.1.2 Unrecoverable Errors An unrecoverable data error is defined as a failure of the drive to recover data from the media. These errors occur due to head/media or write problems. Unrecoverable data errors are only detected during read operations, but not caused by the read. If an unrecoverable data error is detected, a MEDIUM ERROR (03h) in the Sense Key will be reported. Multiple unrecoverable data errors resulting from the same cause are treated as 1 error. 5.1.3 Seek errors A seek error is defined as a failure of the drive to position the heads to the addressed track. After detecting an initial seek error, the drive automatically performs an error recovery process. If the error recovery process fails, a seek positioning error (Error code = 15h or 02h) will be reported with a Hardware error (04h) in the Sense Key. Recoverable seek errors are specified at Less than 10 errors in 108 seeks. Unrecoverable seek errors (Sense Key = 04h) are classified as drive failures. 5.1.4 Interface errors An interface error is defined as a failure of the receiver on a port to recover the data as transmitted by the device port connected to the receiver. The error may be detected as a running disparity error, illegal code, loss of word sync, or CRC error. CONSTELLATION ES.1 SAS PRODUCT MANUAL, REV. G 12