7DQGEHUJ'DWD 6&6,&RPPDQGV

 7DQGEHUJ'/73URGXFW0DQXDO

3(56,67(175(6(59$7,21,1&RPPDQG(KFRQWLQXHG
The figure and table below illustrate and describe the data fields of ReadReservations data parameters.
Bit
Byte
765 4 3210
0 - 3 (MSB)
Generation
(LSB)
4 - 7 (MSB)
Additional Length (Q 7)
(LSB)
8 - Q(MSB)
Reservation Descriptors
(See Figure 5-67 / Table 5-63 for detail of a Descriptor Field) (LSB)

)LJXUH±5HDG5HVHUYDWLRQV3DUDPHWHUV²'DWD)RUPDW

Generation The value in this field is a 32-bit counter in the device server that is
incremented each time a PERSISTENT RESERVATION OUT command
requests a Register, Clear, Pre-empt, or Pre-empt and Clear operation. Note
that PERSISTENT RESERVATION IN commands do not increment the
counter, nor do PERSISTENT RESERVATION OUT commands that perform a
Reserve or Release service action, or by a PERSISTENT RESERVATION
OUT command that is not done due to an error or a reservation conflict. The
value in the Generation field is set to 0 as part of the power on or reset
processes.
The value in the Generation field allows the application client that examines
the value to verify that the configuration of the initiators attached to a logical
unit has not been modified by another application client without any notification
of the application client doing the examination.
Additional Length This f ield contains the count of the number of bytes of Reservation descriptors
(bytes 8 ). Not e that this field contains the number of bytes regardless of
the value prescribed by the Allocation Length field in the commands CDB.
Reservations
Descriptors One Reservation descriptor is reported for each unique persistent reservation
on the logical unit when the PERSISTENT RESERVATION IN command has
indicated a Read Reservations action. Figure 5-67 and Table 5-63 detail the
contents of each Reservation Descriptors field.

7DEOH±5HDG5HVHUYDWLRQV3DUDPHWHUV²)LHOG'HVFULSWLRQV