Quantum LTO 4, User Manual

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SCSI Commands: 15BSCSI Command Status Page 26
3.3 SCSI Command Status
When the tape drive competes a command it responds with a status byte. The
format of the status byte is shown below.
3.3.1 SCSI Status Byte Format
Byte
Bits
7 6 5 4 3 2 1 0
0 Reserved Status Code
3.3.1.1 SCSI Status Byte Field Descriptions
Field Byte Bits Description
Reserved 0 6-7 Always 0
Status
Code 0 0-5 The command status, as shown below.
3.3.2 SCSI Status Codes
Status codes for the LTO drives are shown in the following table.
Description Value When returned
Good Status 00h The command completed without problems
Check Condition 02h A problem occurred during command execution. The sense data
should be examined to determine the nature of the problem.
Busy 08h The drive is unable to accept the command at this time. This is
only returned during the power on sequence or if there are
commands from too many initiator ports outstanding.
Reservation Conflict 18h This is returned if the drive is reserved for an initiator port other
than the one sending the command
Task Set Full 28h (FC and SAS drives only) This is returned if the drive has at least
one task in the task set from an initiator port and a tagged task
from that port cannot be accepted because of a lack of
resources.
ACA Active 30h (FC and SAS drives only) This is returned when an ACA exists
within the drive’s task set and an initiator port issues a command
for that task set when at least one of the following is true:
a) There is a task with the ACA attribute in the task set;
b) The SCSI initiator port issuing the command did not cause
the ACA condition; or
c) The task created to process the command did not have the
ACA attribute and the NACA bit was set to one in the CDB
CONTROL byte of the faulting command.
The SCSI initiator port may reissue the command after the ACA
condition has been cleared.