Fujitsu MBA3073FD, Product Manual

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CHAPTER 7 Error Analysis
7 .1 Sense Data Collection
7.2 Sense Data Analysis
This chapter explains in detail how sense data collected from an HDD is used for troubleshooting. Sense data
reflects an error in the HDD, and helps with troubleshooting.
7.1 Sense Data Collection
7.1.1 Sense 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 initiator. The
initiator 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).
This HDD is equipped with sense data with a byte length of 48. Accordingly, Fujitsu recommends
collecting all 48-byte sense data when the host unit collects sense data.
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.
7.1.2 Sense data format
Figure 7.1 shows the sense data format.
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