Chapter 4 SCSI Commands
PERSISTENT RESERVE IN Command (5Eh)
DLT-S4 Interface Reference Guide
215
Table 117
PERSISTENT
RESERVE IN
Read
Reservation Descriptor — Field
Descriptions
Table 118
describes the available Type values from the Type field of the
PERSISTENT RESERVE IN
Read Reservation parameters. Each of the
codes provides handling instructions for
READ
and
WRITE
operations and
for subsequent attempts to establish persistent reservations (referred to as
“Additional Reservations Allowed” in the table).
Table 118
PERSISTENT
RESERVATION IN
Type Codes
Field
Description
Reservation Key
Contains an 8-byte value that identifies the reservation key under which the
persistent reservation is held.
Scope-Specific
Address
Always set to 0.
Scope
The drive only supports reservations of the entire logical unit. Always set to 0.
Type
Specifies the characteristics of the persistent reservation (see
table 118
for the
applicable Type codes and their meanings).
Code
Name
Description
0h
Obsolete
---
1h
WRITE
Exclusive
READS
: Shared; any application client on any initiator can execute
commands that perform transfers from the drive to the host.
WRITES
: Exclusive; any command from any initiator other than the initiator
that holds the persistent reservation that attempts a transfer to the drive
results in a reservation conflict.
ADDITIONAL RESERVATIONS
: Allowed; any initiator may reserve the logical
unit, extents, or elements as long as the persistent reservations do not conflict
with any reservations already known to the drive.
2h
Obsolete
---