Hitachi HUS154530VLF400 User Manual
Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification
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18.4.3 Terminate Task
The drive does not support Terminate Task. An FCP_RSP with a RSP_CODE of Function Rejected will be returned.
18.4.4 Clear ACA
The drive does not support Clear ACA. An FCP_RSP with a RSP_CODE of Function Rejected will be returned.
18.4.5 Target Reset
The Target Reset Task Management function causes the Target to execute a hard reset, as defined by SAM. This means:
1. Abort all tasks for all Initiators.
2. Release any device reservation.
3. Return all internal states to their initial power-on and default values, as established by PRLI.
4. Set a unit attention condition for all Initiators.
2. Release any device reservation.
3. Return all internal states to their initial power-on and default values, as established by PRLI.
4. Set a unit attention condition for all Initiators.
Target Reset does not affect any login state.
18.4.6 Clear Task Set
Clear Task Set causes the Target to abort all tasks in the task set. The action is equivalent to receiving a series of Abort Task
requests from all Initiators.
requests from all Initiators.
A unit attention condition shall be generated for all other Initiators with tasks in the task set. The Additional Sense Code shall
be Commands cleared by another Initiator.
be Commands cleared by another Initiator.
Previously established conditions such as Mode parameters and reservations are not affected.
18.4.7 Reset LUN
The Reset LUN Task Management function causes the drive to execute a hard reset with the same actions as Target Reset. See
section 18.4.5.
section 18.4.5.
18.5 Miscellaneous
18.5.1 Tags
Using SCSI-FCP, an I/O Process equates to a Fibre Channel Exchange. All IOPs are therefore implicitly tagged by the Fully
Qualified Exchange ID (FQXID).
Qualified Exchange ID (FQXID).
The FQXID is the 80-bit concatenation of the S_ID, D_ID, OX_ID and RX_ID from any frame in the exchange.
18.5.2 Auto-Contingent Allegiance (ACA)
In parallel SCSI-2, a CHECK CONDITION generates sense data for the faulted initiator (the one that got the CHECK CON-
DITION) and either suspends or aborts all commands queued by that Initiator. Execution of the next command from the
faulted Initiator clears the sense data and allows queued commands to resume. This is 'Contingent Allegiance' (CA).
DITION) and either suspends or aborts all commands queued by that Initiator. Execution of the next command from the
faulted Initiator clears the sense data and allows queued commands to resume. This is 'Contingent Allegiance' (CA).
CA requires an interlocked interface to work. In a non-interlocked serial interface, the 'next' command could already be on its
way before the faulted Initiator receives the CHECK CONDITION and sense data could be inadvertently lost.
way before the faulted Initiator receives the CHECK CONDITION and sense data could be inadvertently lost.
In SCSI-3, ACA replaces the SCSI-2 Contingent Allegiance and Extended Contingent Allegiance conditions.