Quantum DLT 8000 Handbuch PDF herunterladen (Seite 281)

SCSI Commands

Quantum DLT 8000 Tape System 5-137

PERSISTENT RESERVATION IN Command (5Eh) (continued)

The figure and table below illustrate and describe the data fields of Read Reservations

data parameters.

Bit

Byte

7 6 5 4 3 2 1 0

0 - 3

(MSB)

Generation

(LSB)

4 - 7

(MSB)

Additional Length (n – 7)

(LSB)

8 - n

(MSB)

Reservation Descriptors

(See Figure 5-67 / Table 5-63 for detail of a Descriptor Field) (LSB)

Figure 5–66 Read Reservations Parameters — Data Format

Table 5–62 Read Reservations Parameters — Field Descriptions

Data Field Description

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 field contains the count of the number of bytes of Reservation descriptors

(bytes 8 – n). Note that this field contains the number of bytes regardless of the

value prescribed by the Allocation Length field in the command’s 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.

1 2 ... 276 277 278 279 280 281 282 283 284 285 286 ... 407 408

Kommentare zu diesen Handbüchern

Keine Kommentare

Quantum DLT 8000 Handbuch Seite 281

Kommentare zu diesen Handbüchern

Verwandte Produkte und Handbücher für Bandlaufwerke Quantum DLT 8000