Seagate Ultra 320 - Manual (Page 166)

152 Parallel SCSI Interface Product Manual, Rev. A
The tests performed in the segments may be the same for the short and extended self-tests. The time required
by a logical unit to complete its extended self-test is reported in the Extended Self-Test Completion Time field
in the Control mode page (see Seagate SCSI Command Reference Manual, Part number 100293068).
8.2.3 Self-test modes
There are two modes for short and extended self-tests: a foreground mode and a background mode. These
modes are described in the following sections.
8.2.3.1 Foreground mode
When a device server receives a SEND DIAGNOSTICs command specifying a self-test to be performed in the
foreground mode, the device server shall return status for that command after the self-test has been com-
pleted. Not all Seagate drives support this mode.
While performing a self-test in the foreground mode, the device server shall respond to all commands except
INQUIRY, REPORT LUNS, and REQUEST SENSE with a CHECK CONDITION status, a sense key of Not
Ready and an additional sense code of Logical Unit Not Ready, Self-Test In Progress.
If a device server is performing a self-test in the foreground mode and a test segment error occurs during the
test, the device server shall update the Self-test results log page (see Seagate SCSI Command Reference
Manual, Part number 100293068) and report CHECK CONDITION status with a sense key of Hardware Error
and an additional sense code of Logical Unit Failed Self-Test. The application client may obtain additional infor-
mation about the failure by reading the Self-test results log page. If the device server is unable to update the
Self-test results log page it shall return a CHECK CONDITION status with a sense key of Hardware Error and
an additional sense code of Logical Unit Unable To Update Self-Test Log.
An application client should reserve the logical unit before initiating a self-test in the foreground mode. An
application client may terminate a self-test that is being performed in the foreground mode using an Abort Task,
ABORT TASK SET, or Clear Task Set task management function. If a task manager receives an Abort Task,
ABORT TASK SET, or Clear Task Set task management function while performing a self-test in the foreground
mode, the it shall abort the self-test and update the Self-test results log page (see Seagate SCSI Command
Reference Manual, Part number 100293068).
8.2.3.2 Background mode
When a device server receives a SEND DIAGNOSTICs command specifying a self-test to be performed in the
background mode, the device server shall return status for that command as soon as the command descriptor
block has been validated.
After returning status for the SEND DIAGNOSTICs command specifying a self-test to be performed in the
background mode, the device server shall initialize the Self-test results log page (see Seagate SCSI Command
Reference Manual, Part number 100293068) as follows. The self-test code from the SEND DIAGNOSTICs
command shall be placed in the Self-Test Code
field in the log page. The Self-Test Results field shall be set to
Fh. After the Self-test results log page is initialized, the device server shall begin the first self-test segment.
While the device server is performing a self-test in the background mode, it shall terminate with a CHECK
CONDITION status any SEND DIAGNOSTICs command it receives that meets one of the following criteria:
a. The Self-Test bit is one; or
b. The Self-Test Code field contains a value other than 000b or 100b.
When terminating the SEND DIAGNOSTICs command, the sense key shall be set to Not Ready and the addi-
tional sense code shall be set to Logical Unit Not Ready, Self-Test In Progress.
While performing a self-test in the background mode, the device server shall suspend the self-test to service
any other commands received with the exceptions listed in Table 65. Suspension of the self-test to service the
command shall occur as soon as possible, but shall never take longer than two seconds.