User's Guide

56 SCSI Commands
• 05h Preempt and Abort – Preempt reservations from another initiator and abort all tasks for all
initiators with the specified reservation key.
• 06h Register and Ignore Existing Key – Register a new reservation key and discard existing
reservation key.
• 07h – Register and Move Registers a reservation key for another I_T nexus and moves the
persistent reservation to that I-T nexus.
Scope – Only logical unit scope is supported, and this field must be a 0h.
Type – This field specifies the type of reservation as follows:
• 3h Exclusive Access – The initiator holding the persistent reservation has exclusive read and
write access. Requests from any other initiators to transfer data to or from the logical unit will result
in a Reservation Conflict.
• 6h Exclusive Access, Registrants Only – Any currently registered initiator has exclusive data
transfer access. Requests from unregistered initiators to transfer data to or from the logical unit will
result in a Reservation Conflict.
• 8h Exclusive Access, All Registrants (only supported if the command is issued to a Media
Changer hosted by an HP tape drive).
Parameter List Length – This field returns 18h (24) to indicate the length of the PERSISTENT RESERVE
OUT parameter list, which is shown in the following table.
Reservation Key – This is an 8-byte reservation key that identifies the initiator. The value must match the
registered reservation key for the I_T nexus except for:
• The Register and Ignore Existing Key service action, where this field is ignored.
• The Register service action for an unregistered I_T nexus, where this field is 0.
Table 52 PERSISTENT RESERVE OUT Parameter List
Bit
Byte
76543210
0
:
7
Reservation Key
8
:
15
Service Action Reservation Key
16
:
19
Scope-Specific Address
20 Reserved
SPEC-
1_PT
ALL_TG
_PT
Rsvd APTPL
21 Reserved
22
:
23
Obsolete
24
:
n
Additional Parameter Data (see Table 53
and Table 54)