Reference Guide

Chapter 4 SCSI Commands
PERSISTENT RESERVE OUT Command (5Fh)
DLT-S4 Interface Reference Guide 228
Table 125 PERSISTENT
RESERVE OUT Parameter List
— Field Descriptions
Table 126 illustrates the fields the application client sets and which the
drive interprets for each service and scope value.
Field Description
Reservation Key Contains an 8-byte token that the application client provides to the drive to identify
the initiator that is the source of the
PERSISTENT RESERVE OUT command. For all
service actions except Register and Ignore Existing Key, the drive verifies that the
Reservation Key in the
PERSISTENT RESERVE OUT command matches the
Reservation Key that is registered for the initiator from which the command is
received. If there is no match, the drive returns a
RESERVATION CONFLICT status.
The Reservation Key of the initiator is valid for all service action and scope values.
Service Action
Reservation Key
Contains information needed for three different service actions: Register, Preempt,
and Preempt & Abort. The Service Action Reservation Key is ignored for all other
service actions.
For the Register service action, the Service Action Reservation Key field contains the
new Reservation Key to be registered.
For the Preempt and the Preempt & Abort service actions, the Service Action
Reservation Key contains the reservation key of the preempted persistent
reservations. For the Preempt and the Preempt & Abort service actions, any failure
of the Service Action Reservation Key to match any registered keys results in the
drive returning a
RESERVATION CONFLICT status.
Scope-Specific
Address
Ignored.
Spec_I_PT Specify Initiator Ports. Must be set to 0.
All_TG_PT All Target Ports. Must be set to 0.
APTPL Activate Persist Through Power Loss. Valid only for Register and Register and
Ignore Existing Key service actions. It is ignored for all other types of service
actions.
If the last valid APTPL bit value the drive received is 0, loss of power in the drive
releases any persistent reservations and removes all reservation keys. If the last
valid APTPL bit value is 1, the drive retains all persistent reservations and all
reservation keys for all initiators even if power is lost and later restored. The most
recently received valid APTPL value from any initiator governs the drive’s
behavior in the event of a power loss.