Seagate ST3400071FC manual Reliability and service, Recoverable Errors, Unrecoverable errors

5.1.1Recoverable Errors

Recovereable 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 recov- ered 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.

5.1.2Unrecoverable errors

Unrecoverable Data Errors (Sense Key = 03h) are specified at less than 1 sector in error per 1014 bits trans- ferred. Unrecoverable Data Errors resulting from the same cause are treated are 1 error for that block.

5.1.3Seek 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.

5.1.4Interface 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. The total error rate for a loop of devices is the sum of the individual device error rates.

5.2Reliability and service

You can enhance the reliability of NL35 Series disc drives by ensuring that the drive receives adequate cooling. Section 6.0 provides temperature measurements and other information that may be used to enhance the ser- vice life of the drive. Section 8.2 provides recommended air-flow information.

18 NL35 Series FC Product Manual, Rev. D