IBM Ultrastar 36LZX, Specifications

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11.1.2 Invalid LUN in Identify Message
There are three different circumstances defined within the SCSI protocol when the response to an invalid
LUN will occur. Each of these result in a different response.
11.1.2 .1 Case 1 - Selection message sequence with Inquiry command
The INQUIRY command is a special case in SCSI. It is used to configure the bus when the drive ID's and
LUN's are not known. The proper response is to return the inquiry data with a peripheral drive type of 1Fh
which indicates that the specified LUN is not supported.
11.1.2 .2 Case 2 - Selection message sequence with any other command
Any other commands except REQUEST SENSE return CHECK CONDITION status when an invalid LUN
is specified in the message sequence following selection. In response to a REQUEST SENSE command
the target shall return sense data. The sense key shall be set to ILLEGAL REQUEST and the additional
sense code shall be set to LOGICAL UNIT NOT SUPPORTED.
11.1.2 .3 Case 3 - After selection message sequence
It is permissible for the initiator to issue multiple IDENTIFY messages during a single command
sequence provided the LUN remains the same. If the LUN is altered, the drive goes to a Bus Free
Phase.
11.1.3 Incorrect Initiator Connection
Incorrect Initiator Connection error is reported if any of the following occur:
Ÿ
an Initiator attempts to establish an I_T_L nexus when an I/O process (either queued or active) with
an I_T_L nexus already exists from a previous connection with the same initiator.
Ÿ
an Initiator attempts to establish an I_T_L_Q nexus when an I_T_L nexus already exists from a pre-
vious connection with the same initiator.
Ÿ
an Initiator attempts to establish an I_T_L nexus when an I_T_L_Q nexus already exists from a pre-
vious connection with the same initiator.
Note: It is not an Incorrect Initiator Connection to send a command without a Queue tag message
when sense is pending on the logical unit for the Initiator that issues the Request Sense command.
(If the command is not Request Sense or Inquiry, sense data is cleared upon receipt of the com-
mand. )
Ÿ
an Initiator attempts to establish an I_T_L_Q nexus when an I/O process (either queued or active)
with an I_T_L_Q nexus already exists from a previous connection with the same initiator.
If any of the above errors occur, all queued I/O processes and active I/O processes associated with the
issuing Initiator on the specified logical unit are terminated. The current I/O process is ended with a
CHECK CONDITION status, the sense key is set to ABORTED COMMAND, and the additional sense
code is set to OVERLAPPED COMMANDS ATTEMPTED. Status is only returned for the current I/O
process.
Ultrastar 36LZX hard disk drive specifications
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