Diagnostics and Maintenance

b)When an error is detected in the hardware function test, the HDDs post the CHECK CONDITION status for all I/O operation request except the REQUEST SENSE command. The error status is not cleared even if the error information (sense data) is read. Only when the power is turned off or re-turned on, the status can be cleared. When this status is cleared, the HDDs execute the initial self-diagnostics again (see item (1)).

Refer to Subsection 4.4.1 “SEND DIAGNOSTIC (1D)” of the SAS INTERFACE MANUAL for further details of the command specifications.

6.1.2Test programs

The basic operations of the HDD itself can be checked with the self-diagnostic function. However, to check general operations such as the host system and interface operations in a status similar to the normal operation status, a test program that runs on the host system must be used.

The structure and functions of the test program depend on the user system requirements. Generally, it is recommended to provide a general input/output test program that includes devices connected to the input/output devices on other I/O ports.

Including the following test items in the test program is recommended to test the HDD functions generally.

(1)Interface test

The operations of the data buffer on the HDDs are checked with the WRITE BUFFER and READ BUFFER commands.

(2)Basic operation test

The basic operations of the HDDs are checked by executing self-diagnosis with the SEND DIAGNOSTIC command (see Subsection 6.1.1).

(3)Random/sequential read test

The positioning (seek) operation and read operation are tested in random access and sequential access modes with the READ, READ EXTENDED, or VERIFY command.

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Fujitsu MBB2147RC, MBB2073RC manual Test programs