CHAPTER 7 Error Analysis

7.1Error Analysis Information Collection

7.2Sense Data Analysis

This chapter explains in detail how sense data collected from a disk drive is used for troubleshooting. Sense data reflects an error in the disk drive, and helps with troubleshooting.

A sense key, additional sense code, and additional sense code qualifier, taken from various sense data are repeated. Also in this chapter, troubleshooting is performed using these three codes. Unless otherwise specified, "sense data" means the above three codes. When sense data is represented as (x-xx-xx), the leftmost x is a sense key, the middle xx is an additional sense code, and the rightmost x is an additional sense code qualifier.

7.1Error Analysis Information Collection

7.1.1Sense data

When HDDs post a CHECK CONDITION status, the current command or queued command is cleared. In such a case, the HDDs generate sense data about the command-issuing INIT. The INIT can read the sense data by reading the sense data added to the response frame of the command where an error occurred (Auto Sense function).

7.1.2Sense key, additional sense code, and additional sense code qualifier

If an error is detected in a disk drive, the error status is indicated in the sense data collected from the disk drive. Figure 7.1 shows the positions of a sense key, additional sense code, and additional sense code qualifier.

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Fujitsu MAX3147RC, MAX3036RC, MAX3073RC manual Error Analysis Information Collection Sense Data Analysis